Hepatitis A

What is hepatitis?

The liver is one of the organs that helps with digestion but is not part of the digestive tract. It is the largest organ in the body and carries out many important functions, such as making bile, changing food into energy, and cleaning alcohol and poisons from the blood.

Hepatitis is inflammation of the liver that sometimes causes permanent damage. It is caused by viruses, bacteria, certain medications, or alcohol. Generally, symptoms of hepatitis include fever, jaundice, and an enlarged liver. There are several types of hepatitis.

What is hepatitis A?

Hepatitis A is a highly contagious and sometimes serious liver disease caused by the hepatitis A virus. Once called infectious hepatitis, today it is more commonly known as hepatitis A. Approximately one-third of Americans have been exposed to hepatitis A.

Hepatitis A does not result in chronic infection, but complete recovery from hepatitis A can be slow. In adult patients with hepatitis A, the illness may last for at least one month, with recovery taking up to six months. Some 15 percent of patients may have a relapse of the disease and may be impaired over 6 to 9 months. Also, some patients require hospitalization for hepatitis A.

What are the symptoms of hepatitis A?

The following are the most common symptoms of hepatitis A. However, each individual may experience symptoms differently. Symptoms of hepatitis A often resemble flu-like symptoms. Symptoms may include:

fever
chills
general feeling of weakness
loss of appetite
nausea
abdominal discomfort
dark urine
jaundice - yellowing of the skin and eyes.
diarrhea

In some adults, and in children, especially in those younger than 6 years of age, there are often no symptoms.

The symptoms of hepatitis A may resemble other medical conditions or problems. Always consult your physician for a diagnosis.

What causes hepatitis A?

This type of hepatitis is usually spread by fecal-oral contact or fecal-infected food and water, and may also be spread by blood-borne infection (which is rare). The following is a list of modes of transmission for hepatitis A:

consuming food made by someone who touched infected feces
drinking water that is contaminated by infected feces (a problem in developing countries with poor sewage removal)
touching an infected person's feces, which may occur with poor handwashing
outbreaks may occur in large childcare centers, especially when there are children in diapers
residents of American Indian reservations or Native Alaskan villages where hepatitis A may be more common
sexual contact with an infected person

Generally, casual contact in school or the workplace does not cause spread of the virus.

What are the risk factors for hepatitis A?

Children, teens, and adults who may be at high risk of hepatitis A include the following:

people traveling to areas of where hepatitis A is prevalent, including, but not limited to: Africa, Asia (except Japan), the Mediterranean basin, Eastern Europe, the Middle East, Central and South America, Mexico, and parts of the Caribbean
people living in or relocating to any community in the US or abroad with one or more recorded hepatitis A outbreaks within the past five years
military personnel
people who engage in high-risk sexual activity
users of illegal intravenous (IV) drugs
hemophiliacs and other recipients of therapeutic blood products
employees of daycare centers
institutional care workers
laboratory workers who handle live hepatitis A virus
people who handle primate animals that may be carrying the hepatitis A virus

Hepatitis A is sometimes called a traveler's disease because it is the most frequently occurring, vaccine-preventable infection in travelers. However, it is possible to become infected with hepatitis A virus without ever leaving the United States.

Prevention of hepatitis A:

In addition to avoiding risky behaviors, there are two methods for prevention of hepatitis A:

immune globulin
a preparation of antibodies that is given both before anticipated exposure to the hepatitis A virus and soon after exposure.
hepatitis A vaccine
Researchers at the National Institute of Allergy and Infectious Diseases have found the genes that make hepatitis A virulent. However, when the researchers altered those genes to weaken the virus, the virus quickly reverted itself back to its natural infectious form, making it difficult to create an improved vaccine. Currently, the vaccine consists of killed hepatitis A virus. Because the vaccine is not given routinely, please consult your physician if you have any questions about its use.

The Centers for Disease Control and Prevention (CDC) recommend the hepatitis A vaccine for the following groups who are at risk for the infection, as well as for anyone who wants to have the vaccine:

people traveling to or working in countries that have high or intermediate rates of hepatitis A
children in communities that have high rates of hepatitis A and periodic outbreaks of the disease
men who have sex with men
illegal drug users
people at occupational risk for the disease
people with chronic liver disease
people with clotting-factor disorders such as hemophilia

Prevention protocols when traveling include:

Avoid untreated tap water in drinks or ice cubes.
Drink and brush your teeth using only bottled or boiled water.
Do not eat unpeeled fruits, salads, uncooked vegetables, or raw shellfish (i.e., clams, oysters, and mussels).
Do not eat food or drink beverages (except commercially bottled beverages) bought from street vendors.

Hepatitis A may also be avoided through vaccination with immune globulin (IG) or hepatitis A vaccine.

IG contains antibodies (or protective proteins) to the hepatitis A virus. IG is relatively inexpensive and provides short-term protection against hepatitis A disease (generally three to five months).

Hepatitis A vaccine helps provide longer-term protection against hepatitis A. It is estimated that resistance may last for up to 20 years.