Hepatitis A

Description

Hepatitis A is a liver disease caused by the hepatitis A virus. Hepatitis A can affect anyone. In the United States, hepatitis A can occur in situations ranging from isolated cases of disease to widespread epidemics.  

 

Good personal hygiene and proper sanitation can help prevent hepatitis A. Vaccines are also available for long-term prevention of hepatitis A virus infection in persons 12 months of age and older. Immune globulin is available for short-term prevention of hepatitis A virus infection in individuals of all ages.

SIGNS & SYMPTOMS

Adults will have signs and symptoms more often than children.

•jaundice

•fatigue

•abdominal pain

•loss of appetite

•nausea

•diarrhea

•fever

 

CAUSE

•Hepatitis A virus (HAV)

LONG-TERM EFFECTS

•There is no chronic (long-term) infection.

•Once you have had hepatitis A, you cannot get it again.

•About 15% of people infected with HAV will have prolonged or relapsing symptoms over a 6-9 month period.

TRANSMISSION

•HAV is found in the stool (feces) of persons with hepatitis A. 

•HAV is usually spread from person to person by putting something in the mouth (even though it might look clean) that has been contaminated with the stool of a person with hepatitis A. 

PERSONS AT RISK for INFECTION

•Household contacts of infected persons

•Sex contacts of infected persons

•Persons, especially children, living in areas with increased rates of hepatitis A during the baseline period of 1987-1997

•Travelers to countries where hepatitis A is common

•Men who have sex with men

•Users of injection and non-injection drugs

PREVENTION

•Hepatitis A vaccine is the best protection.

•Short-term protection against hepatitis A is available from immune globulin. It can be given before and within 2 weeks of coming in contact with HAV. 

•Always wash your hands with soap and water after using the bathroom, changing a diaper, and before preparing and eating food.

VACCINE RECOMMENDATIONS

Vaccine is recommended for the following persons from 12 months of age and older:

•All children at age 1 year (i.e., 12–23 months)

•Travelers to countries where hepatitis A is common

•Men who have sex with men

•Users of injection and non-injection drugs

•Persons with clotting-factor disorders (e.g., hemophilia)

•Persons with chronic liver disease

•Children living in areas with increased rates of hepatitis A during the baseline period of 1987-1997

•Persons who work with HAV in a laboratory setting

 

TRENDS & STATISTICS 

 

•Hepatitis A occurs in epidemics both nationwide and in communities.

•Before hepatitis A vaccine became available, the number of reported cases reached 35,000 per year.

•In the late 1990s, hepatitis A vaccine was more widely used and the number of cases reached historic lows.

•One-third of Americans have evidence of past infection (immunity).

 Hepatitis B

DESCRIPTION

Hepatitis B is a serious disease caused by a virus that attacks the liver. The virus, which is called hepatitis B virus (HBV), can cause lifelong infection, cirrhosis (scarring) of the liver, liver cancer, liver failure, and death.

Hepatitis B vaccine is available for all age groups to prevent hepatitis B virus infection.

SIGNS & SYMPTOMS

About 30% of persons have no signs or symptoms.  

Signs and symptoms are less common in children than adults.

•jaundice

•fatigue

•abdominal pain

•loss of appetite

•nausea, vomiting 

•joint pain

CAUSE

•Hepatitis B virus (HBV)

TRANSMISSION

•Occurs when blood from an infected person enters the body of a person who is not infected.

•HBV is spread through having sex with an infected person without using a condom (the efficacy of latex condoms in preventing infection with HBV is unknown, but their proper use might reduce transmission), by sharing drugs, needles, or "works" when injecting drugs, through needlesticks or sharps exposures on the job, or from an infected mother to her baby during birth.

Persons at risk for HBV infection might also be at risk for infection with hepatitis C virus (HCV) or HIV.

RISK GROUPS

 

•Persons with multiple sex partners or diagnosis of a sexually transmitted disease

•Men who have sex with men

•Sex contacts of infected persons

•Injection-drug users

•Household contacts of chronically infected persons

•Infants born to infected mothers

•Infants/children of immigrants from areas with high rates of HBV infection Health-care and public safety workers with exposure to blood

•Hemodialysis patients

PREVENTION

•Hepatitis B vaccine is the best protection.

•If you are having sex, but not with one steady partner, use latex condoms correctly and every time you have sex. The efficacy of latex condoms in preventing infection with HBV is unknown, but their proper use might reduce transmission.

•If you are pregnant, you should get a blood test for hepatitis B. Infants born to HBV-infected mothers should be given HBIG (hepatitis B immune globulin) and vaccine within 12 hours after birth.

•Do not shoot drugs; if you shoot drugs, stop and get into a treatment program; if you can't stop, never share drugs, needles, syringes, water, or "works", and get vaccinated against hepatitis A and B.

•Do not share personal care items that might have blood on them (razors, toothbrushes).

•Consider the risks if you are thinking about getting a tattoo or body piercing. You might get infected if the tools have someone else's blood on them or if the artist or piercer does not follow good health practices.

•If you have or had hepatitis B, do not donate blood, organs, or tissue.

•If you are a health-care or public safety worker, get vaccinated against hepatitis B, and always follow routine barrier precautions and safely handle needles and other sharps.

VACCINE RECOMMENDATIONS

•Hepatitis B vaccine has been available since 1982.

•Routine vaccination of 0-18 year olds

•Vaccination of risk groups of all ages

LONG-TERM EFFECTS WITHOUT VACCINATION

Chronic infection occurs in:

•90% of infants infected at birth

•30% of children infected at age 1–5 years 

•6% of persons infected after age 5 years 

Death from chronic liver disease occurs in:

•15%–25% of chronically infected persons

CONTRAINDICATIONS TO VACCINE

•A serious allergic reaction to a prior dose of hepatitis B vaccine or a vaccine component is a contraindication to further doses of hepatitis B vaccine. The recombinant vaccines that are licensed for use in the United States are synthesized by Saccharomyces cerevisiae (common bakers' yeast), into which a plasmid containing the gene for HBsAg has been inserted. Purified HBsAg is obtained by lysing the yeast cells and separating HBsAg from the yeast components by biochemical and biophysical techniques. Persons allergic to yeast should not be vaccinated with vaccines containing yeast.

TREATMENT & MEDICAL MANAGEMENT

•HBV infected persons should be evaluated by their doctor for liver disease.

•Adefovir dipivoxil, interferon alfa-2b, pegylated interferon alfa-2a, lamivudine, entecavir, and telbivudine are six drugs used for the treatment of persons with chronic hepatitis B.

•These drugs should not be used by pregnant women.

•Drinking alcohol can make your liver disease worse.

TRENDS & STATISTICS

 

 

•Number of new infections per year has declined from an average of 260,000 in the 1980s to about 60,000 in 2004.

•Highest rate of disease occurs in 20-49-year-olds.

•Greatest decline has happened among children and adolescents due to routine hepatitis B vaccination. 

•Estimated 1.25 million chronically infected Americans, of whom 20-30% acquired their infection in childhood.

 

Typhoid Fever

How is typhoid fever spread?

Salmonella Typhi lives only in humans. Persons with typhoid fever carry the bacteria in their bloodstream and intestinal tract. In addition, a small number of persons, called carriers , recover from typhoid fever but continue to carry the bacteria. Both ill persons and carriers shed S. Typhi in their feces (stool).  
 
You can get typhoid fever if you eat food or drink beverages that have been handled by a person who is shedding S. Typhi or if sewage contaminated with S. Typhi bacteria gets into the water you use for drinking or washing food. Therefore, typhoid fever is more common in areas of the world where handwashing is less frequent and water is likely to be contaminated with sewage.  
 
Once S. Typhi bacteria are eaten or drunk, they multiply and spread into the bloodstream. The body reacts with fever and other signs and symptoms.

Where in the world do you get typhoid fever?

Typhoid fever is common in most parts of the world except in industrialized regions such as the United States, Canada, western Europe, Australia, and Japan. Therefore, if you are traveling to the developing world, you should consider taking precautions. Over the past 10 years, travelers from the United States to Asia, Africa, and Latin America have been especially at risk.

How can you avoid typhoid fever?

Two basic actions can protect you from typhoid fever:

1.Avoid risky foods and drinks.

2.Get vaccinated against typhoid fever.

It may surprise you, but watching what you eat and drink when you travel is as important as being vaccinated. This is because the vaccines are not completely effective. Avoiding risky foods will also help protect you from other illnesses, including travelers' diarrhea, cholera, dysentery, and  
hepatitis A.

"Boil it, cook it, peel it, or forget it"

 

 

If you drink water, buy it bottled or bring it to a rolling boil for 1 minute before you drink it. Bottled carbonated water is safer than uncarbonated water.

 

 

Ask for drinks without ice unless the ice is made from bottled or boiled water. Avoid popsicles and flavored ices that may have been made with contaminated water.

 

 

Eat foods that have been thoroughly cooked and that are still hot and steaming.

 

 

Avoid raw vegetables and fruits that cannot be peeled. Vegetables like lettuce are easily contaminated and are very hard to wash well.

 

 

When you eat raw fruit or vegetables that can be peeled, peel them yourself. (Wash your hands with soap first.) Do not eat the peelings.

 

 

Avoid foods and beverages from street vendors. It is difficult for food to be kept clean on the street, and many travelers get sick from food bought from street vendors.

Getting vaccinated

If you are traveling to a country where typhoid is common, you should consider being vaccinated against typhoid. Visit a doctor or travel clinic to discuss your vaccination options.  
 
Remember that you will need to complete your vaccination at least 1 week before you travel so that the vaccine has time to take effect. Typhoid vaccines lose effectiveness after several years; if you were vaccinated in the past, check with your doctor to see if it is time for a booster vaccination. Taking antibiotics will not prevent typhoid fever; they only help treat it.

What are the signs and symptoms of typhoid fever?

Persons with typhoid fever usually have a sustained fever as high as 103° to 104° F (39° to 40° C). They may also feel weak, or have stomach pains, headache, or loss of appetite. In some cases, patients have a rash of flat, rose-colored spots. The only way to know for sure if an illness is typhoid fever is to have samples of stool or blood tested for the presence of S. Typhi .

What do you do if you think you have typhoid fever?

If you suspect you have typhoid fever, see a doctor immediately. If you are traveling in a foreign country, you can usually call the U.S. consulate for a list of recommended doctors.  
 
You will probably be given an antibiotic to treat the disease. Three commonly prescribed antibiotics are ampicillin, trimethoprim-sulfamethoxazole, and ciprofloxacin. Persons given antibiotics usually begin to feel better within 2 to 3 days, and deaths rarely occur. However, persons who do not get treatment may continue to have fever for weeks or months, and as many as 20% may die from complications of the infection.

Typhoid fever's danger doesn't end when symptoms disappear

Even if your symptoms seem to go away, you may still be carrying S. Typhi . If so, the illness could return, or you could pass the disease to other people. In fact, if you work at a job where you handle food or care for small children, you may be barred legally from going back to work until a doctor has determined that you no longer carry any typhoid bacteria.  
 
If you are being treated for typhoid fever, it is important to do the following:  
 
Keep taking the prescribed antibiotics for as long as the doctor has asked you to take them.  
Wash your hands carefully with soap and water after using the bathroom, and do not prepare or serve food for other people. This will lower the chance that you will pass the infection on to someone else.

Have your doctor perform a series of stool cultures to ensure that no S. Typhi bacteria remain in your body.

 

E. coli (Escherichia coli O157:H7)

What is Escherichia coli O157:H7?

E. coli O157:H7 is one of hundreds of strains of the bacterium Escherichia coli. Although most strains are harmless, this strain produces a powerful toxin that can cause severe illness. E. coli O157:H7 has been found in the intestines of healthy cattle, deer, goats, and sheep.

E. coli O157:H7 was first recognized as a cause of illness in 1982 during an outbreak of severe bloody diarrhea; the outbreak was traced to contaminated hamburgers. Since then, more infections in the United States have been caused by eating undercooked ground beef than by any other food.

The combination of letters and numbers in the name of the bacterium refers to the specific markers found on its surface and distinguishes it from other types of E. coli.

How is E. coli O157:H7 spread?

The organism can be found on most cattle farms, and it is commonly found in petting zoos and can live in the intestines of healthy cattle, deer, goats, and sheep. Meat can become contaminated during slaughter, and organisms can be accidentally mixed into meat when it is ground. Bacteria present on the cow's udders or on equipment may get into raw milk. In a petting zoo, E.coli O157:H7 can contaminate the ground, railings, feed bins, and fur of the animals.

Eating meat, especially ground beef, that has not been cooked sufficiently to kill E. coli O157:H7 can cause infection. Contaminated meat looks and smells normal. The number of organisms required to cause disease is very small.

Among other known sources of infection are consumption of sprouts, lettuce, spinach, salami, unpasteurized milk and juice, and by swimming in or drinking sewage-contaminated water.

Bacteria in loose stool of infected persons can be passed from one person to another if hygiene or hand washing habits are inadequate. This is particularly likely among toddlers who are not toilet trained. Family members and playmates of these children are at high risk of becoming infected.

Young children typically shed the organism in their feces for a week or two after their illness resolves. Older children and adults rarely carry the organism without symptoms.

What illness does E. coli O157:H7 cause?

People generally become ill from E. coli O157:H7 two to eight days (average of 3-4) after being exposed to the bacteria. Escherichia coli O157:H7 infection often causes severe bloody diarrhea and abdominal cramps. Sometimes the infection causes non-bloody diarrhea or no symptoms. Usually little or no fever is present, and the illness resolves in 5 to 10 days.

In some persons, particularly children under 5 years of age and the elderly, the infection can also cause a complication called hemolytic uremic syndrome (HUS), in which the red blood cells are destroyed and the kidneys fail. About 8% of persons whose diarrheal illness is severe enough that they seek medical care develop this complication. In the United States, HUS is the principal cause of acute kidney failure in children, and most cases of HUS are caused by E. coli O157:H7.

How is E. coli O157:H7 infection diagnosed?

Infection with E. coli O157:H7 is diagnosed by detecting the bacterium in the stool. About one-third of laboratories that culture stool still do not test for E. coli O157:H7, so it is important to request that the stool specimen be tested on sorbitol-MacConkey (SMAC) agar for this organism. All persons who suddenly have diarrhea with blood should get their stool tested for E. coli O157:H7.

How is the illness treated?

Most people recover without antibiotics or other specific treatment within 5 to 10 days. Antibiotics should not be used to treat this infection. There is no evidence that antibiotics improve the course of disease, and it is thought that treatment with some antibiotics could lead to kidney complications. Antidiarrheal agents, such as loperamide (Imodium®), should also be avoided.

In some people, E. coli O157:H7 infection can cause a complication called hemolytic uremic syndrome (HUS), a life-threatening condition that is usually treated in an intensive care unit. Blood transfusions and kidney dialysis are often required. With intensive care, the death rate for hemolytic uremic syndrome is 3%-5%.

What are the long-term consequences of infection?

Persons who only have diarrhea usually recover completely.

A small proportion of persons with hemolytic uremic syndrome (HUS) have immediate complications with lifelong implications, such as blindness, paralysis, persistent kidney failure, and the effects of having part of their bowel removed. Many persons with hemolytic uremic syndrome have mild abnormalities in kidney function many years later.

What can be done to prevent the infection?

Cattle are the principal source of E. coli O157 infection; they carry E. coli O157 in their intestines. Changes in the preparation of animals for slaughter and in slaughter and processing methods could decrease the contamination of carcasses with E. coli O157 and the subsequent contamination of meat. Testing ground beef for E. coli O157 and withholding it from the market until the test is negative, as many meat producers began doing in 2002, is probably partly responsible for the subsequent decrease in illnesses.

Cattle manure is an important source of E. coli O157. Manure can contaminate the environment, including streams that flow through produce fields and are used for irrigation, pesticide application, or washing. Collaborative efforts are needed to decrease environmental contamination and improve the safety of produce.

What can you do to prevent E. coli O157:H7 infection?

•Cook all ground beef and hamburger thoroughly. Because ground beef can turn brown before disease-causing bacteria are killed, use a digital instant-read meat thermometer to ensure thorough cooking. Ground beef should be cooked until a thermometer inserted into several parts of the patty, including the thickest part, reads at least 160º F. Persons who cook ground beef without using a thermometer can decrease their risk of illness by not eating ground beef patties that are still pink in the middle.

•If you are served an undercooked hamburger or other ground beef product in a restaurant, send it back for further cooking. You may want to ask for a new bun and a clean plate, too.

•Avoid spreading harmful bacteria in your kitchen. Keep raw meat separate from ready-to-eat foods. Wash hands, counters, and utensils with hot soapy water after they touch raw meat. Never place cooked hamburgers or ground beef on the unwashed plate that held raw patties. Wash meat thermometers in between tests of patties that require further cooking.

•Drink only pasteurized milk, juice, or cider. Commercial juice with an extended shelf-life that is sold at room temperature (e.g. juice in cardboard boxes, vacuum sealed juice in glass containers) has been pasteurized, although this is generally not indicated on the label. Juice concentrates are also heated sufficiently to kill pathogens.

•Wash fruits and vegetables under running water, especially those that will not be cooked. Be aware that bacteria are sticky, so even thorough washing may not remove all contamination. Remove the outer leaves of leafy vegetables. Children under 5 years of age, immunocompromised persons, and the elderly should avoid eating alfalfa sprouts until their safety can be assured. Persons at high risk of complications from foodborne illness may choose to consume cooked vegetables and peeled fruits.

•Drink municipal water that has been treated with chlorine or another effective disinfectant.

•Avoid swallowing lake or pool water while swimming.

•Make sure that persons with diarrhea, especially children, wash their hands carefully with soap after bowel movements to reduce the risk of spreading infection, and that persons wash hands after changing soiled diapers. Anyone with a diarrheal illness should avoid swimming in public pools or lakes, sharing baths with others, and preparing food for others.

 

Cholera

What is cholera? 
 
Cholera is an acute, diarrheal illness caused by infection of the intestine with the bacterium Vibrio cholerae. The infection is often mild or without symptoms, but sometimes it can be severe. Approximately one in 20 infected persons has severe disease characterized by profuse watery diarrhea, vomiting, and leg cramps. In these persons, rapid loss of body fluids leads to dehydration and shock. Without treatment, death can occur within hours.

How does a person get cholera?  
 
A person may get cholera by drinking water or eating food contaminated with the cholera bacterium. In an epidemic, the source of the contamination is usually the feces of an infected person. The disease can spread rapidly in areas with inadequate treatment of sewage and drinking water.  
 
The cholera bacterium may also live in the environment in brackish rivers and coastal waters. Shellfish eaten raw have been a source of cholera, and a few persons in the United States have contracted cholera after eating raw or undercooked shellfish from the Gulf of Mexico. The disease is not likely to spread directly from one person to another; therefore, casual contact with an infected person is not a risk for becoming ill.

What is the risk for cholera in the United States?  
 
In the United States, cholera was prevalent in the 1800s but has been virtually eliminated by modern sewage and water treatment systems. However, as a result of improved transportation, more persons from the United States travel to parts of Africa, Asia, or Latin America where epidemic cholera is occurring . U.S. travelers to areas with epidemic cholera may be exposed to the cholera bacterium. In addition, travelers may bring contaminated seafood back to the United States; foodborne outbreaks have been caused by contaminated seafood brought into this country by travelers.

What should travelers do to avoid getting cholera?  
 
The risk for cholera is very low for U.S. travelers visiting areas with epidemic cholera. When simple precautions are observed, contracting the disease is unlikely.  
 
All travelers to areas where cholera has occured should observe the following recommendations:

 

Drink only water that you have boiled or treated with chlorine or iodine. Other safe beverages include tea and coffee made with boiled water and carbonated, bottled beverages with no ice.

 

Eat only foods that have been thoroughly cooked and are still hot, or fruit that you have peeled yourself.

 

Avoid undercooked or raw fish or shellfish, including ceviche.

 

Make sure all vegetables are cooked avoid salads.

 

Avoid foods and beverages from street vendors.

 

Do not bring perishable seafood back to the United States.

A simple rule of thumb is "Boil it, cook it, peel it, or forget it. "

Is a vaccine available to prevent cholera?  
 
A recently developed oral vaccine for cholera is licensed and available in other countries (Dukoral from SBL Vaccines). The vaccine appears to provide somewhat better immunity and have fewer adverse effects than the previously available vaccine. However, CDC does not recommend cholera vaccines for most travelers, nor is the vaccine available in the United States . Further information about Dukoral can be obtained from the manufacturers:

Can cholera be treated? 
 
Cholera can be simply and successfully treated by immediate replacement of the fluid and salts lost through diarrhea. Patients can be treated with oral rehydration solution, a prepackaged mixture of sugar and salts to be mixed with water and drunk in large amounts. This solution is used throughout the world to treat diarrhea. Severe cases also require intravenous fluid replacement. With prompt rehydration, fewer than 1% of cholera patients die.  
 
Antibiotics shorten the course and diminish the severity of the illness, but they are not as important as rehydration. Persons who develop severe diarrhea and vomiting in countries where cholera occurs should seek medical attention promptly.

How long will the current epidemic last?  
 
Predicting how long a Cholera epidemic will last  is difficult. The cholera epidemic in Africa has lasted more than 30 years. In areas with inadequate sanitation, a cholera epidemic cannot be stopped immediately, and, although far fewer cases have been reported from Latin America and Asia in recent years, there are no signs that the global Cholera pandemic will end soon. Major improvements in sewage and water treatment systems are needed in many countries to prevent future epidemic cholera.

What is the U.S. government doing to combat cholera?  
 
U.S. and international public health authorities are working to enhance surveillance for cholera, investigate cholera outbreaks, and design and implement preventive measures. The Centers for Disease Control and Prevention investigates epidemic cholera wherever it occurs and trains laboratory workers in proper techniques for identification of V. cholerae. In addition, the Centers for Disease Control and Prevention provides information on diagnosis, treatment, and prevention of cholera to public health officials and educates the public about effective preventive measures.  
 
The U.S. Agency for International Development is sponsoring some of the international government activities and is providing medical supplies to affected countries.  
 
The Environmental Protection Agency is working with water and sewage treatment operators in the United States to prevent contamination of water with the cholera bacterium.  
 
The Food and Drug Administration is testing imported and domestic shellfish for V. cholerae and monitoring the safety of U.S. shellfish beds through the shellfish sanitation program.  
 
With cooperation at the state and local, national, and international levels, assistance will be provided to countries where cholera is present, and the risk to U.S. residents will remain small.

 

Malaria

What is Malaria?

Malaria is a serious and sometimes fatal disease caused by a parasite that commonly infects a certain type of mosquito which feeds on humans. People who get malaria are typically very sick with high fevers, shaking chills, and flu-like illness. Four kinds of malaria parasites can infect humans: Plasmodium falciparum, P. vivax, P. ovale, and P. malariae. Infection with P. falciparum, if not promptly treated, may lead to death. Although malaria can be a deadly disease, illness and death from malaria can usually be prevented.

About 1,300 cases of malaria are diagnosed in the United States each year. The vast majority of cases in the United States are in travelers and immigrants returning from malaria-risk areas, many from sub-Saharan Africa and South Aisa.

The World Health Organization estimates that each year 300-500 million cases of malaria occur and more than 1 million people die of malaria, especially in developing countries. Most deaths occur in young children. For example, in Africa, a child dies from malaria every 30 seconds. Because malaria causes so much illness and death, the disease is a great drain on many national economies. Since many countries with malaria are already among the poorer nations, the disease maintains a vicious cycle of disease and poverty.

How is malaria transmitted?

Usually, people get malaria by being bitten by an infective female Anopheles mosquito. Only Anopheles mosquitoes can transmit malaria and they must have been infected through a previous blood meal taken on an infected person. When a mosquito bites an infected person, a small amount of blood is taken in which contains microscopic malaria parasites. About 1 week later, when the mosquito takes its next blood meal, these parasites mix with the mosquito's saliva and are injected into the person being bitten.

Because the malaria parasite is found in red blood cells of an infected person, malaria can also be transmitted through blood transfusion, organ transplant, or the shared use of needles or syringes contaminated with blood. Malaria may also be transmitted from a mother to her unborn infant before or during delivery ("congenital" malaria).

Is malaria a contagious disease?

No. Malaria is not spread from person to person like a cold or the flu, and it cannot be sexually transmitted. You cannot get malaria from casual contact with malaria-infected people, such as sitting next to someone who has malaria.

Who is at risk for malaria?

Anyone can get malaria. Most cases occur in people who live in countries with malaria transmission. People from countries with no malaria can become infected when they travel to countries with malaria or through a blood transfusion (although this is very rare). Also, an infected mother can transmit malaria to her infant before or during delivery.

Who are the people most at risk of getting very sick and dying from malaria?

Plasmodium falciparum causes severe and life-threatening malaria; this parasite is very common in many countries in Africa south of the Sahara desert. People who are heavily exposed to the bites of mosquitoes infected with P. falciparum are most at risk of dying from malaria. People who have little or no immunity to malaria, such as young children and pregnant women; or travelers coming from areas with no malaria, are more likely to become very sick and die. Poor people living in rural areas who lack knowledge, money, or access to health care are at greater risk for this disease. As a result of all these factors, an estimated 90% of deaths due to malaria occur in Africa south of the Sahara; most of these deaths occur in children under 5 years of age.

What are the signs and symptoms of malaria?

Symptoms of malaria include fever and flu-like illness, including shaking chills, headache, muscle aches, and tiredness. Nausea, vomiting, and diarrhea may also occur. Malaria may cause anemia and jaundice (yellow coloring of the skin and eyes) because of the loss of red blood cells. Infection with one type of malaria, Plasmodium falciparum, if not promptly treated, may cause kidney failure, seizures, mental confusion, coma, and death.

How soon will a person feel sick after being bitten by an infected mosquito?

For most people, symptoms begin 10 days to 4 weeks after infection, although a person may feel ill as early as 7 days or as late as 1 year later. Two kinds of malaria, P. vivax and P. ovale, can occur again (relapsing malaria). In P. vivax and P. ovale infections, some parasites can remain dormant in the liver for several months up to about 4 years after a person is bitten by an infected mosquito. When these parasites come out of hibernation and begin invading red blood cells ("relapse"), the person will become sick.

How do I know if I have malaria for sure?

Most people, at the beginning of the disease, have fever, sweats, chills, headaches, malaise, muscles aches, nausea and vomiting. Malaria can very rapidly become a severe and life-threatening disease. The surest way for you and your health-care provider to know whether you have malaria is to have a diagnostic test where a drop of your blood is examined under the microscope for the presence of malaria parasites. If you are sick and there is any suspicion of malaria (for example, if you have recently traveled in a malaria-risk area) the test should be performed without delay.

Preventing Malaria During Travel

I will be traveling outside of the US to an area with malaria; how do I find out what is the best drug to take against malaria?

CDC Travelers' Health destination pages give detailed information on the proper drugs to take for the area you are visiting and specific prevention tips.

Many effective antimalarial drugs are available. Your health care provider and you will decide on the best drug for you based on your travel plans, medical history, age, drug allergies, pregnancy status, and other health factors.

To allow enough time for the drugs to become effective and for a pharmacy to prepare any special doses of medicine (especially doses for children and infants), visit your health care provider 4-6 weeks before travel.

What is known about the long term effects of drugs that are commonly used to prevent and treat malaria?

In general, most drugs used to prevent and treat malaria have been shown to be well tolerated for at least 1 year or more.

Is it safe to buy my malaria drugs in the malaria-risk country where I will be traveling?

Buying medications abroad has its risks. The drugs could be of poor quality because of the way they are produced. The drugs could contain contaminants or they could be counterfeit drugs and therefore may not provide you the protection you need against malaria. In addition, some medications that are sold overseas are not used anymore in the United States or were never sold here. These drugs may not be safe or their safety has never been evaluated.

It would be best to purchase all the medications that you need before you leave the United States. As a precaution, note the name of the medication(s) and the name of the manufacturer(s). That way, in case of accidental loss, you can replace the drug(s) abroad at a reliable vendor.

Isn't there a malaria vaccine? And if not, why?

There is currently no malaria vaccine approved for human use. The malaria parasite is a complex organism with a complicated life cycle. Its antigens are constantly changing and developing a vaccine against these varying antigens is very difficult. In addition, scientists do not yet totally understand the complex immune responses that protect humans against malaria. However, many scientists all over the world are working on developing an effective vaccine. Because other methods of fighting malaria, including drugs, insecticides, and bed nets, have not succeeded in eliminating the disease, the search for a vaccine is considered to be one of the most important research projects in public health.

Malaria and Infants and Children

Should infants and children be given antimalarial drugs?

Yes, but not all types of malaria drugs. Children of any age can get malaria and any child traveling to a malaria-risk area should be on an antimalarial drug. However, some antimalarial drugs are not suitable for children. Doses are based on the child's weight.

If I am taking an antimalarial drug and breastfeeding, will my baby be protected from malaria because of the medication transferred in my breast milk?

No. Based on experience with other antimalarial drugs, the quantity of drug transferred in breast milk is not likely to be enough to provide protection against malaria for the infant.

After Returning from a Malaria Risk Area

How long after returning from an area with malaria could I develop malaria?

Any traveler who becomes ill with a fever or flu-like illness while traveling, and up to 1 year after returning home should immediately seek professional medical care. You should tell your healthcare provider that you have been traveling in a malaria-risk area.

Treating Malaria

When should malaria be treated?

The disease should be treated early in its course, before it becomes serious and life-threatening. Several good antimalarial drugs are available, and should be taken early on. The most important step is to think about malaria if you are presently in, or have recently been in, an area with malaria, so that the disease is diagnosed and treated in time.

What is the treatment for malaria?

Malaria can be cured with prescription drugs. The type of drugs and length of treatment depend on the type of malaria, where the person was infected, their age, whether they are pregnant, and how sick they are at the start of treatment.

When is malaria self-treatment recommended?

Travelers who are taking effective malaria preventive drugs but who will be in very remote areas may decide, in consultation with their healthcare provider, to take along antimalarial mediation for self-treatment. Malaria self-treatment should begin right away if fever, chills, or other influenza-like illness occurs and if professional medical care is not available within 24 hours. Self-treatment of a possible malarial infection is only a temporary measure and immediate medical care is important.

The CDC Malaria Branch (Malaria Hotline 770-488-7788) can provide consultation to health-care providers on other potential options for self-treatment if atovaquone/proguanil cannot be used.

If I get malaria, will I have it for the rest of my life?

No, not necessarily. Malaria can be treated. If the right drugs are used, people who have malaria can be cured and all the malaria parasites can be cleared from their body. However, the disease can continue if it is not treated or if it is treated with the wrong drug. Some drugs are not effective because the parasite is resistant to them. Some people with malaria may be treated with the right drug, but at the wrong dose or for too short a period of time.

Two types (species) of parasites, Plasmodium vivax and P. ovale, have liver stages and can remain in the body for years without causing sickness. If not treated, these liver stages may re-activate and cause malaria attacks ("relapses") after months or years without symptoms. People diagnosed with P. vivax or P. ovale are often given a second drug to help prevent these relapses. Another type of malaria, P. malariae, if not treated, has been known to stay in the blood of some people for several decades.

However, in general, if you are correctly treated for malaria, the parasites are eliminated and you are no longer infected with malaria.

Where Malaria Occurs

Where does malaria occur?

Malaria typically is found in warmer regions of the world -- in tropical and subtropical countries. Higher temperatures allow the Anopheles mosquito to thrive. Malaria parasites, which grow and develop inside the mosquito, need warmth to complete their growth before they are mature enough to be transmitted to humans.

Malaria occurs in over 100 countries and territories. More than 40% of the world's population is at risk. Large areas of Central and South America, Hispaniola (the Caribbean island that is divided between Haiti and the Dominican Republic), Africa, South Asia, Southeast Asia, the Middle East, and Oceania are considered malaria-risk areas.

Yet malaria does not occur in all warm climates. For example, malaria has been eliminated in some countries with warm climates, while a few other countries have no malaria because Anopheles mosquitoes are not found there.

In some countries, malaria is said to exist in "rural" areas. How would one know if an area is rural vs urban?

What constitutes a rural area can vary by country. In general, urbanization can be said to involve both population size and economic development of an area in which there is concentrated commercial activity, such as manufacturing, the sale of goods and services, and transportation. Rural areas tend to have less commercial activity, less population density, more green space, and agriculture may be a main feature.

 

Encephalitis

CLINICAL FEATURES

•Aseptic meningitis or encephalitis. Many cases have only fever with headache

•Can progress to focal paralysis, intractable seizures, coma and death

ETIOLOGIC AGENT

•Several alpha-, flavi- and bunya- viruses; chiefly, St. Louis encephalitis (SLE), western equine encephalitis (WEE), Venezuelan equine encephalitis (VEE), eastern equine encephalitis (EEE), La Crosse virus and other California serogroup viruses

INCIDENCE

•Varies with occurrence and intensity of epidemic transmission; usually 150-3,000 cases/year

SEQUELAE

•Neurologic sequelae in 30% of EEE cases; 10% of SLE cases

•Case fatality rate of 30% in EEE cases; 5% of SLE cases

COSTS

•$150 million - includes estimated cost of vector control and surveillance activities

TRANSMISSION

•Chiefly mosquito-borne

RISK GROUPS

•SLE - elderly; low income areas

•La Crosse encephalitis - children

•WEE - rural residents of the West

 

Rabies

How do people get rabies?

People usually get get rabies from the bite of a rabid animal. It is also possible, but quite rare, that people may get rabies if infectious material from a rabid animal, such as saliva, gets directly into their eyes, nose, mouth, or a wound.

Can I get rabies in any way other than an animal bite?

Non-bite exposures to rabies are very rare. Scratches, abrasions, open wounds, or mucous membranes contaminated with saliva or other potentially infectious material (such as brain tissue) from a rabid animal constitute non-bite exposures. Occasionally reports of non-bite exposure are such that postexposure prophylaxis is given.

Inhalation of aerosolized rabies virus is also a potential non-bite route of exposure, but other than laboratory workers, most people are unlikely to encounter an aerosol of rabies virus.

Other contact, such as petting a rabid animal or contact with the blood, urine or feces (e.g., guano) of a rabid animal, does not constitute an exposure and is not an indication for prophylaxis.

How soon after an exposure should I seek medical attention?

Medical assistance should be obtained as soon as possible after an exposure. There have been no vaccine failures in the United States (i.e., someone developed rabies) when postexposure prophylaxis (PEP) was given promptly and appropriately after an exposure.

What medical attention do I need if I am exposed to rabies?

One of the most effective methods to decrease the chances for infection involves thorough washing of the wound with soap and water. Specific medical attention for someone exposed to rabies is called postexposure prophylaxis or PEP. In the United States, postexposure prophylaxis consists of a regimen of one dose of immune globulin and five doses of rabies vaccine over a 28-day period. Rabies immune globulin and the first dose of rabies vaccine should be given by your health care provider as soon as possible after exposure. Additional doses or rabies vaccine should be given on days 3, 7, 14, and 28 after the first vaccination. Current vaccines are relatively painless and are given in your arm, like a flu or tetanus vaccine.

Will the rabies vaccine make me sick?

Adverse reactions to rabies vaccine and immune globulin are not common. Newer vaccines in use today cause fewer adverse reactions than previously available vaccines. Mild, local reactions to the rabies vaccine, such as pain, redness, swelling, or itching at the injection site, have been reported. Rarely, symptoms such as headache, nausea, abdominal pain, muscle aches, and dizziness have been reported. Local pain and low-grade fever may follow injection of rabies immune globulin.

What if I cannot get rabies vaccine on the day I am supposed to get my next dose?

Consult with your doctor or state or local public health officials for recommended times if there is going to be a change in the recommended schedule of shots. Rabies prevention is a serious matter and changes should not be made in the schedule of doses.

Can rabies be transmitted from one person to another?

The only well-documented documented cases of rabies caused by human-to-human transmission occurred among 8 recipients of transplanted corneas, and recently among three recipients of solid organs (see MMWR article). Guidelines for acceptance of suitable cornea and organ donations, as well as the rarity of human rabies in the United States, reduce this risk. In addition to transmission from cornea and organ transplants, bite and non-bite exposures inflicted by infected humans could theoretically transmit rabies, but no such cases have been documented. Casual contact, such as touching a person with rabies or contact with non-infectious fluid or tissue (urine, blood, feces) does not constitute an exposure and does not require postexposure prophylaxis. In addition, contact with someone who is receiving rabies vaccination does not constitute rabies exposure and does not require postexposure prophylaxis.

 

Yellow Fever

Yellow fever occurs only in Africa and South America. In South America sporadic infections occur almost exclusively in forestry and agricultural workers from occupational exposure in or near forests.

In Africa the virus is transmitted in three geographic regions:

•principally and foremost, in the moist savanna zones of West and Central Africa during the rainy season,

•secondly, outbreaks occur occasionally in urban locations and villages in Africa,

•and finally, to a lesser extent, in jungle regions.

Yellow fever is a viral disease transmitted between humans by a mosquito. Yellow fever is a very rare cause of illness in travelers, but most countries have regulations and requirements for yellow fever vaccination that must be met prior to entering the country. General precautions to avoid mosquito bites should be followed. These include the use of insect repellent, protective clothing, and mosquito netting. Yellow fever vaccine is a live virus vaccine which has been used for several decades. A single dose confers immunity lasting 10 years or more. If a person is at continued risk of yellow fever infection, a booster dose is needed every 10 years. Adults and children over 9 months can take this vaccine. Administration of immune globulin does not interfere with the antibody response to yellow fever vaccine.

This vaccine is only administered at designated yellow fever vaccination centers.

Who Should Not Receive the Yellow Fever Vaccine?

Yellow fever vaccine generally has few side effects; fewer than 5% of vaccinees develop mild headache, muscle pain, or other minor symptoms 5 to 10 days after vaccination. Under almost all circumstances, there are four groups of people who should not receive the vaccine unless the risk of yellow fever disease exceeds the small risk associated with the vaccine. These people should obtain either a waiver letter prior to travel or delay travel to an area with active yellow fever transmission:

•Yellow fever vaccine should never be given to infants under 6 months of age due to a risk of viral encephalitis developing in the child. In most cases, vaccination should be deferred until the child is 9 to 12 months of age.

•Pregnant women should not be vaccinated because of a theoretical risk that the developing fetus may become infected from the vaccine.

•Persons hypersensitive to eggs should not receive the vaccine because it is prepared in embryonated eggs. If vaccination of a traveler with a questionable history of egg hypersensitivity is considered essential, an intradermal test dose may be administered under close medical supervision. (Notify your doctor prior to vaccination if you think that you may be allergic to the vaccine or to egg products.)

•Persons with an immunosuppressed condition associated with AIDS or HIV infection, or those whose immune system has been altered by either diseases such as leukemia and lymphoma or through drugs and radiation should not receive the vaccine. People with asymptomatic HIV infection may be vaccinated if exposure to yellow fever cannot be avoided.

If you have one of these conditions, your doctor will be able to help you decide whether you should be vaccinated, delay your travel, or obtain a waiver. In all cases, the decision to immunize an infant between 6 and 9 months of age, a pregnant woman, or an immunocompromised patient should be made on an individual basis. The physician should weigh the risks of exposure and contracting the disease against the risks of immunization, and possibly consider alternative means of protection.

Medical Waivers

Most countries will accept a medical waiver for persons with a medical reason for not receiving the vaccination. CDC recommends obtaining written waivers from consular or embassy officials before departure. Travelers should contact the embassy or consulate for specific advice. Typically, a physician's letter stating the reason for withholding the vaccination and written on letterhead stationery is required by the embassy or consulate. The letter should bear the stamp used by a health department or official immunization center to validate the International Certificate of Vaccination.

 

Altitude Sickness

Travelers whose itineraries will take them above an altitude of 1,829-2,438 m (6,000-8,000 ft) should be aware of the risk of altitude illness (1). Travelers are exposed to higher altitudes in a number of ways: by flying into a high-altitude city, by driving or riding a bus or train to a high-altitude destination, or by hiking or climbing in high mountains. Examples of high-altitude cities with airports are Cuzco, Peru (3,000 m; 11,000 ft); La Paz, Bolivia (3,444 m; 11,300 ft); and Lhasa, Tibet (3,749 m; 12,500 ft).

Travelers vary considerably in their susceptibility to altitude illness, and no screening tests are available to predict someone’s risk for altitude illness. Susceptibility to altitude illness appears to be inherent in some way and is not affected by training or physical fitness. How a traveler has responded in the past to exposure to high altitude is the most reliable guide for future trips but is not infallible. 

Travelers with underlying medical conditions, such as congestive heart failure, myocardial ischemia (angina), sickle cell disease, or any form of pulmonary insufficiency, should be advised to consult a doctor familiar with high-altitude medical issues before undertaking such travel. The risk of new ischemic heart disease in previously healthy travelers does not appear to be increased at high altitudes (2). Travelers with diabetes can travel safely to high altitude, but they must exercise more caution in checking their blood glucose. Diabetic ketoacidosis may be triggered by altitude illness and may be made more difficult to treat by the use of acetazolamide (see below). Not all glucose meters may read accurately at high altitudes (3).

Most people do not have visual problems at high altitude. However, at very high altitudes some persons who have had incisional radial keratotomy (a procedure widely performed from the late 1970s to the early 1990s) may develop acute farsightedness (4). The laser surgery for vision correction that replaced radial keratotomy (e.g., Lasik and other procedures) is not associated with visual disturbances at high altitudes.

Altitude illness is the result of traveling to a higher altitude faster than the body can adapt to that new altitude. Fluid leakage from blood vessels appears to be the main cause of symptoms. Altitude illness is divided into three syndromes: acute mountain sickness (AMS), high-altitude cerebral edema (HACE), and high-altitude pulmonary edema (HAPE). AMS is the most common form of altitude illness and, while it can occur at altitudes as low as 1,219-1,829 m (4,000-6,000 ft) (5), most often it occurs in abrupt ascents to >2,743 m (>9,000 ft) (6). The symptoms resemble those of an alcohol hangover: headache, fatigue, loss of appetite, nausea, and, occasionally, vomiting. The onset of AMS is delayed, usually beginning 6-12 hours after arrival at a higher altitude, but occasionally 24 hours after ascent.

HACE is considered a severe progression of AMS. In addition to the AMS symptoms, lethargy becomes profound, confusion can manifest, and ataxia will be demonstrated during the tandem gait test. A person with symptoms of AMS who fails the tandem gait test has HACE by definition, and immediate descent is mandatory. Death from HACE can ensue within 6-24 hours of developing ataxia.

HAPE can occur by itself or in conjunction with HACE. The initial symptoms are increased breathlessness with exertion, and eventually increased breathlessness at rest. The diagnosis can usually be made when breathlessness fails to resolve after several minutes of rest. At this point, it is critical to descend to a lower altitude. HAPE can be more rapidly fatal than HACE.

Determining an itinerary that will avoid any occurrence of altitude illness is difficult because of variations in individual susceptibility, as well as in starting points and terrain. The main point of instructing travelers about altitude illness is not to prevent any possibility of altitude illness, but to prevent death from altitude illness. The onset of symptoms and clinical course is sufficiently slow and predictable that there is no reason for someone to die from altitude illness unless trapped by weather or geography in a situation in which descent is impossible. The three rules that travelers should be made aware of to prevent death from altitude illness are:

•Know the early symptoms of altitude illness; acknowledge and verbalize when they are present.

•Never ascend to sleep at a higher altitude when experiencing any of the symptoms of altitude illness, no matter how minor they seem.

•Descend if the symptoms become worse while resting at the same altitude.

Studies have shown that travelers who are on organized group treks to high-altitude locations are more likely to die of altitude illness than travelers who are by themselves (7). This is most likely the result of group pressure (whether perceived or real) and a fixed itinerary. The most important aspect of preventing severe altitude illness is to refrain from further ascent until all symptoms of altitude illness have disappeared.

Children are as susceptible to altitude illness as adults, and young children who cannot talk can show very nonspecific symptoms, such as loss of appetite and irritability. There are no studies or case reports of harm to a fetus if the mother travels briefly to high altitude during pregnancy. However, it may be prudent to recommend that pregnant women stay below 3,658 m (12,000 ft) if possible. The dangers of having a complication of pregnancy in remote, mountainous terrain should also be discussed.

Three medications have been shown to be useful in the prevention and treatment of altitude illness. Acetazolamide (Diamox) can prevent AMS when taken before ascent and can speed recovery if taken after symptoms have developed. The drug appears to work by acidifying the blood, which causes an increase in respiration and thus aids in acclimatization. An effective dose that minimizes the common side effects of increased urination and paresthesias of the fingers and toes is 125 mg every 12 hours, beginning the day of ascent. However, most clinical trials have been done with higher doses of 250 mg two or three times a day (8). Allergic reactions to acetazolamide are extremely rare, but the drug is related to sulfonamides and should not be used by sulfa-allergic persons, unless a trial dose is taken in a safe environment before travel. People with a history of severe penicillin allergy have occasionally had an allergic reaction to acetazolamide (9).

Dexamethasone has been shown to be effective in the prevention and treatment of AMS and HACE (10,11). The drug prevents or improves symptoms, but there is no evidence that it aids acclimatization. Thus, there is a risk of a sudden onset or worsening of symptoms if the traveler stops taking the drug while ascending. It is preferable for the traveler to use acetazolamide to prevent AMS while ascending and to reserve the use of dexamethasone to treat symptoms while trying to descend. The adult dosage is 4 mg every 6 hours.

HAPE is always associated with increased pulmonary artery pressure. Drugs that can selectively lower pulmonary artery pressure have been shown to be of benefit in preventing and treating HAPE. Nifedipine has been shown to prevent and ameliorate HAPE in persons who are particularly susceptible to HAPE (12). The adult dosage is 10-20 mg every 8 hours. Sildenafil citrate (Viagra) and related compounds can also selectively lower pulmonary artery pressure, with less effect on systemic blood pressure. Preliminary studies suggest that this class of drug may prove useful in prevention and treatment of HAPE (13).

Newer medications have recently been tried to help prevent AMS and HAPE. When taken before ascent, gingko biloba, an herbal remedy, was shown to reduce the symptoms of AMS in adults in two small trials, but a third trial failed to confirm the findings of the first two. Gingko biloba has not yet been compared directly to acetazolamide. Inhaled salmeterol (a beta-adrenergic agonist) was dem-onstrated to help prevent HAPE in a small group of climbers who had previously shown susceptibility to HAPE (14). Whether salmeterol will prove beneficial in a more general population remains to be seen. The mechanism of action of salmeterol suggests that it could be of benefit in treating already established HAPE, but there are no studies yet to confirm this. Salmeterol was chosen for prophylactic studies because of a longer duration of action. The less expensive albuterol may also be effective, but no studies utilizing this drug at altitude have been done.

For trekking groups and expeditions going into remote high-altitude areas, where descent to a lower altitude could be problematic, a pressurization bag (such as the Gamow bag) can prove extremely beneficial (15). Persons with altitude illness can be zipped into the bag, and a foot pump can increase the pressure inside the bag by 2 lbs. per in2, mimicking a descent of 1,500-1,800m (5,000-6,000 ft), depending on the starting altitude. The total packed weight of the bag and pump is approximately 6.5 kg.

For most travelers, the best way to avoid altitude illness is to plan a gradual ascent, with extra rest days at intermediate altitudes. If ascent must be rapid, acetazolamide may be used prophylactically, and dexamethasone and pulmonary artery pressure-lowering drugs, such as nifedipine or sildenafil, may be carried for emergencies (16,17).

Tetanus

What causes tetanus?

Tetanus is caused by a toxin (poison) produced by a bacterium, Clostridium tetani. The C. tetani bacteria cannot grow in the presence of oxygen. They produce spores that are very difficult to kill as they are resistant to heat and many chemical agents.

How does tetanus spread?

C. tetani spores can be found in the soil and in the intestines and feces of many household and farm animals and humans. The bacteria usually enter the human body through a puncture (in the presence of anaerobic [low oxygen] conditions, the spores will

germinate). Tetanus is not spread from person to person.

How long does it take to show signs of tetanus after being exposed?

The incubation period varies from 3-21 days, with an average of eight days. The further the injury site is from the central nervous system, the longer the incubation period. The shorter the incubation period, the higher the risk of death.

What are the symptoms of tetanus?

The symptoms of tetanus are caused by the tetanus toxin acting on the central nervous system. In the most common form of tetanus, the first sign is spasm of the jaw muscles, followed by stiffness of the neck, difficulty in swallowing, and stiffness of the abdominal

muscles. Other signs include fever, sweating, elevated blood pressure, and rapid heart rate. Spasms often occur, which may last for several minutes and continue for 3-4 weeks. Complete recovery, if it occurs, may take months.

How serious is tetanus?

Tetanus has a high fatality rate; during 1998-2000, the case-fatality rate for reported tetanus in the United States was 18%.

What are possible complications from tetanus?

Laryngospasm (spasm of the vocal cords) is a complication that can lead to interference with breathing. Patients can also break their spine or long bones from convulsions. Other possible complications include hypertension, abnormal heart rhythm, and secondary infections, which are common because of prolonged hospital stays. Obviously, the high possibility of death is a major complication.

What kind of injuries might allow tetanus to enter

the body?

Tetanus bacilli live in the soil, so the most dangerous kind of injury involves possible contamination with dirt, animal feces, and manure. Although we have traditionally worried about deep puncture wounds, in reality many types of injuries can allow

tetanus bacilli to enter the body. In recent years, a higher proportion of cases had minor wounds than had major ones, probably because severe wounds were more likely to be properly managed. People have become infected with tetanus following surgery, burns, lacerations, abrasions, crush wounds, ear infections, dental infections, animal bites, abortion, pregnancy, body piercing and tattooing, and injection drug use. People can also get tetanus from splinters.

I stepped on a nail in our yard. What should I do?

Any wound that may involve contamination with tetanus bacilli should be attended to as soon as possible. Treatment depends on your vaccination status and the nature of the wound. In all cases, the wound should be cleaned. Seek treatment immediately and bring your immunization record with you. With wounds that involve the possibility of tetanus

contamination, a patient with an unknown or incomplete history of tetanus vaccination needs a tetanus- and diphtheria-containing shot (Td or Tdap) and a dose of tetanus immune globulin (TIG) as soon as possible. A person with a documented series of three tetanus and diphtheria-containing shots (Td or Tdap) who has received a booster dose within the last ten years should be protected. However, to ensure adequate protection, a booster dose of vaccine may still be given if it has been more than five years since the last dose and the wound is other than clean and minor.

Is there a treatment for tetanus?

There is no .cure. for tetanus once a person develops symptoms, just supportive treatment and management of complications. The best treatment is prevention through immunization.

Can you get tetanus more than once?

Yes! Tetanus disease does not cause immunity because so little of the potent toxin is required to cause the disease. Persons recovering from tetanus should begin or complete the vaccination series.

What kind of vaccine is the tetanus toxoid?

The tetanus vaccine is an inactivated toxin (poison) called a toxoid. It is made by growing the bacteria in a liquid medium and purifying and inactivating the toxin. Because it is not a live vaccine, a person’s immunity tends to decline with time, which is why booster doses are recommended.

Who should get this vaccine?

Infants should receive DTaP vaccine (or DT-pediatric if they cannot receive the pertussis component) as part of their routine immunization. Adults should be given a routine booster dose of Td every 10 years. Adults without documentation of ever receiving the

basic series of tetanus and diphtheria toxoids should first receive a primary series of three doses, properly spaced. A single dose of Tdap is recommended for

Who should NOT receive tetanus toxoid?

People who had a serious allergic reaction to one dose of tetanus toxoid should not receive another. Persons with a moderate or severe acute illness should postpone receiving the vaccine until they are improved. Most reactions to the combined DTaP vaccine are due to the pertussis component. Please see the .Pertussis. section for more information on possible precautions to the use of this vaccine.

Can the vaccine cause tetanus?

No.

 

Diphtheria

Clinical Features

Respiratory diphtheria presents as a sore throat with low-grade fever and an adherent membrane of the tonsils, pharynx, or nose. Neck swelling is usually present in severe disease. Cutaneous diphtheria presents as infected skin lesions which lack a characteristic appearance.

Etiologic Agent

Toxin-producing strains of Corynebacterium diphtheriae.

Incidence

Approximately 0.001 cases per 100,000 population in the U.S. since 1980; before the introduction of vaccine in the 1920s incidence was 100-200 cases per 100,000 population. Diphtheria remains endemic in developing countries. The countries of the former Soviet Union have reported >150,000 cases in an epidemic which began in 1990.

Complications

Myocarditis, polyneuritis, and airway obstruction are common complications of respiratory diphtheria; death occurs in 5%-10% of respiratory cases. Complications and deaths are much less frequent in cutaneous diphtheria.

Transmission

Direct person- to-person transmission by intimate respiratory and physical contact. Cutaneous lesions are important in transmission.

Risk Groups

In the pre-vaccine era, children were at highest risk for respiratory diphtheria. Recently, diphtheria has primarily affected adults in the sporadic cases reported in the U.S. and in the large outbreaks in Russia and New Independent States of the Former Soviet Union.

Surveillance

National surveillance through the National Electronic Telecommunications System for Surveillance (NETSS). Cases also identified by requests for diphtheria antitoxin (DAT); since 1997 DAT is available in the U.S. only through CDC.

Trends

Respiratory diphtheria has become a rare disease in the U.S. (0-5 cases per year.) An increasing proportion of cases occurs among older children and adults; in the prevaccination era, younger children were most often affected.

 

Polio

What is polio?

Polio is a disease caused by a virus. It enters a child’s (or adult’s) body through the mouth. Sometimes it does not cause serious illness. But sometimes it causes paralysis (can’t move arm or leg). It can kill people who get it, usually by paralyzing the muscles that help them breathe.

Polio used to be very common in the United States. It paralyzed and killed thousands of people a year before we had a vaccine for it.

Why get vaccinated?

Inactivated Polio Vaccine (IPV) can prevent polio.

History: A 1916 polio epidemic in the United States killed 6,000 people and paralyzed 27,000 more. In the early 1950’s there were more than 20,000 cases of polio each year. Polio vaccination was begun in 1955. By 1960 the number of cases had dropped to about 3,000, and by 1979 there were only about 10. The success of polio vaccination in the U.S. and other countries sparked a world-wide effort to eliminate polio.

Today: No wild polio has been reported in the United States for over 20 years. But the disease is still common in some parts of the world. It would only take one case of polio from another country to bring the disease back if we were not protected by vaccine. If the effort to eliminate the disease from the world is successful, some day we won’t need polio vaccine. Until then, we need to keep getting our children vaccinated.

Who should get polio vaccine and when?

IPV is a shot, given in the leg or arm, depending on age. Polio vaccine may be given at the same time as other vaccines.

Children

Most people should get polio vaccine when they are children. Children get 4 doses of IPV, at these ages:

􀀳 A dose at 2 months 􀀳 A dose at 6-18 months

􀀳 A dose at 4 months 􀀳 A booster dose at 4-6 years

Adults

Most adults do not need polio vaccine because they were already vaccinated as children. But three groups of adults are at higher risk and should consider polio vaccination:

(1) people traveling to areas of the world where polio is common,

(2) laboratory workers who might handle polio virus, and

(3) health care workers treating patients who could have polio.

Adults in these three groups who have never been

vaccinated against polio should get 3 doses of IPV:

􀀳 The first dose at any time,

􀀳 The second dose 1 to 2 months later,

􀀳 The third dose 6 to 12 months after the second.

Adults in these three groups who have had 1 or 2 doses of polio vaccine in the past should get the remaining 1 or 2 doses. It doesn’t matter how long it has been since the earlier dose(s).

Adults in these three groups who have had 3 or more doses of polio vaccine (either IPV or OPV) in the past may get a booster dose of IPV.

Ask your health care provider for more information.

Some people should not get IPV or should wait.

These people should not get IPV:

• Anyone who has ever had a life-threatening allergic reaction to the antibiotics neomycin, streptomycin or polymyxin B should not get the polio shot.

• Anyone who has a severe allergic reaction to a polio shot should not get another one.

These people should wait:

• Anyone who is moderately or severely ill at the time the shot is scheduled should usually wait until they recover before getting polio vaccine. People with minor illnesses, such as a cold, may be vaccinated.

Ask your health care provider for more information.

What are the risks from IPV?

Some people who get IPV get a sore spot where the shot was given. The vaccine used today has never been known to cause any serious problems, and most people don’t have any problems at all with it. However, a vaccine, like any medicine, could cause serious problems, such as a severe allergic reaction. The risk of a polio shot causing serious harm, or death, is extremely small.

 

Measles

Description

A respiratory disease caused by a virus. 
 
The virus normally grows in the cells that line the back of the throat and in the cells that line the lungs.

Symptoms

Rash, high fever, cough, runny nose, and red, watery eyes (lasts about a week).

Complications

Diarrhea, ear infections, pneumonia, encephalitis, seizures, and death

Approximately 20% of reported measles cases experience one or more complications. These complications are more common among children under 5 years of age and adults over 20 years old.

Measles causes ear infections in nearly one out of every 10 children who get it. As many as one out of 20 children with measles gets pneumonia, and about one child in every 1,000 who get measles will develop encephalitis. (This is an inflammation of the brain that can lead to convulsions, and can leave your child deaf or mentally retarded.) For every 1,000 children who get measles, one or two will die from it. Measles can also make a pregnant woman have a miscarriage, give birth prematurely, or have a low-birth-weight baby.

In developing countries, where malnutrition and vitamin A deficiency are prevalent, measles has been known to kill as many as one out of four people. It is the leading cause of blindness among African children. Measles kills almost 1 million children in the world each year.

Transmission

Spread by contact with an infected person, through coughing and sneezing (highly contagious)

The disease is highly contagious, and can be transmitted from 4 days prior to the onset of the rash to 4 days after the onset. If one person has it, 90% of their susceptible close contacts will also become infected with the measles virus.

The virus resides in the mucus in the nose and throat of the infected person. When that person sneezes or coughs, droplets spray into the air. The infected mucus can land in other people’s noses or throats when they breathe or put their fingers in their mouth or nose after handling an infected surface. The virus remains active and contagious on infected surfaces for up to 2 hours. Measles spreads so easily that anyone who is not immunized will probably get it, eventually.

Vaccine

Measles vaccine (contained in MMR, MR and measles vaccines) can prevent this disease.

The MMR vaccine is a live, attenuated (weakened), combination vaccine that protects against the measles, mumps, and rubella viruses. It was first licensed in the combined form in 1971 and contains the safest and most effective forms of each vaccine.

It is made by taking the measles virus from the throat of an infected person and adapting it to grow in chick embryo cells in a laboratory. As the virus becomes better able to grow in the chick embryo cells, it becomes less able to grow in a child’s skin or lungs. When this vaccine virus is given to a child it replicates only a little before it is eliminated from the body. This replication causes the body to develop an immunity that, in 95% of children, lasts for a lifetime.

A second dose of the vaccine is recommended to protect those 5% who did not develop immunity in the first dose and to give "booster" effect to those who did develop an immune response.

Who needs it?

You do NOT need the measles, mumps, rubella vaccine (MMR) if:

•You had blood tests that show you are immune to measles, mumps, and rubella.

•You are a man born before 1957.

•You are a woman born before 1957 who is sure she is not having more children, has already had rubella vaccine, or has had a positive rubella test.

•You already had two doses of MMR or one dose of MMR plus a second dose of measles vaccine.

•You already had one dose of MMR and are not at high risk of measles exposure.

You SHOULD get the measles vaccine if you are not among the categories listed above, and:

•You are a college student, trade school student, or other student beyond high school.

•You work in a hospital or other medical facility.

•You travel internationally, or are a passenger on a cruise ship.

•You are a woman of childbearing age.

 

Mumps

Description

An acute viral illness caused by the mumps virus.

Symptoms

Fever, headache, muscle aches, tiredness, and loss of appetite; followed by swelling of salivary glands. The parotid salivary glands (which are located within your cheek, near your jaw line, below your ears) are most frequently affected.

Complications

Severe complications are rare. However, mumps can cause:

•inflammation of the brain and/or tissue covering the brain and spinal cord (encephalitis/meningitis)

•inflammation of the testicles (orchitis)

•inflammation of the ovaries and/or breasts (oophoritis and mastitis)

•spontaneous abortion

•deafness, usually permanent

Transmission

The mumps virus replicates in the upper respiratory tract and is spread through direct contact with respiratory secretions or saliva or through fomites.

The infectious period or time that an infected person can transmit mumps to a non-infected person is from 3 days before symptoms appear to about 9 days after the symptoms appear.

The incubation time, which is the period from when a person is exposed to virus to the onset of any symptoms, can vary from 16 to 18 days (range 12-25 days).

Diagnosis

Should be made by your physician and laboratory testing may be required.

Treatment

Currently, there is no specific treatment for mumps.

Prevention

The mumps vaccine, which is contained in the MMR (measles, mumps, and rubella) vaccine, can prevent this disease.

Vaccine

Mumps vaccine (contained in MMR) can prevent this disease.

Who needs it?

You do NOT need the measles, mumps, rubella vaccine (MMR) if:

•You had blood tests that show you are immune to measles, mumps, and rubella.

•You are a male born before 1957.

•You are a female born before 1957 who is sure she is not having more children, has already had rubella vaccine, or has had a positive rubella test.

•You already had two doses of MMR or one dose of MMR plus a second dose of measles vaccine.

•You already had one dose of MMR and are not at high risk of measles or mumps exposure.

You SHOULD get the MMR vaccine if you are not among the categories listed above, and

•You are a college student, trade school student, or other student beyond high school.

•You work in a hospital or other medical facility.

•You travel internationally, or are a passenger on a cruise ship.

•You are a woman of childbearing age.

 

Rubella

Description

An acute viral disease that causes fever and rash

Symptoms

Rash and fever for two to three days (mild disease in children and young adults)

Complications

Birth defects if acquired by a pregnant woman: deafness, cataracts, heart defects, mental retardation, and liver and spleen damage (at least a 20% chance of damage to the fetus if a woman is infected early in pregnancy)

Transmission

Spread by contact with an infected person, through coughing and sneezing

Vaccine

Rubella vaccine (contained in MMR vaccine) can prevent this disease.

Who needs it?

You do NOT need the measles, mumps, rubella vaccine (MMR) if:

•You had blood tests that show you are immune to measles, mumps, and rubella.

•You are a man born before 1957.

•You are a woman born before 1957 who is sure she is not having more children, has already had rubella vaccine, or has had a positive rubella test.

•You already had two doses of MMR or one dose of MMR plus a second dose of measles vaccine.

•You already had one dose of MMR and are not at high risk of measles or mumps exposure.

You SHOULD get the MMR  vaccine if you are not among the categories listed above, and

•You are a college student, trade school student, or other student beyond high school.

•You work in a hospital or other medical facility.

•You travel internationally, or are a passenger on a cruise ship.

•You are a woman of childbearing age.

All above information on individual diseases is taken from http://www.cdc.gov