What is hepatitis A, and what causes it?
Hepatitis A is a liver disease caused by the Hepatitis A virus (HAV). It is one of the most widely reported diseases that is preventable by a vaccine.
Other viruses can cause hepatitis, most commonly the Hepatitis B and C viruses. However, hepatitis has many causes, including certain medications, long-term alcohol use, and exposure to certain industrial chemicals. Viral hepatitis can be spread from one person to another, but the other types of hepatitis cannot.
How is Hepatitis A spread?
The virus is spread mainly by oral contact with stool containing the virus. If contaminated stool gets into the water or food supply, the virus may infect anyone who drinks the water or eats the food. This is how most people around the world become infected with hepatitis A.
In the United States, most people become infected through contact with a household member who has the virus (such as when changing a diaper) or a sex partner who is infected. Sometimes large groups of people become infected after eating in a restaurant. This usually happens when an employee with the virus prepares food after not washing his or her hands well after using the bathroom. Outbreaks may also occur in day care centers and other facilities which involve close contact.
In rare cases, Hepatitis A can be spread through sexual contact or contact with blood from a person who has the virus circulating in his or her bloodstream. The virus is present in the blood before symptoms appear. Transmission through blood transfusions, while possible, seldom occurs.
What are the symptoms of hepatitis A?
People infected with Hepatitis A may develop these symptoms:
Extreme tiredness (fatigue)
Fever
Sore muscles
Headache
Pain on the right side of the abdomen, under the rib cage (where the liver is located)
Nausea
Loss of appetite and weight loss
Yellowing of the skin and the white part of the eyes (jaundice), sometimes along with dark urine and clay-colored stools. Jaundice is less common in children and young adults than in older people.
Symptoms usually last about 2 weeks. You can spread the virus to other people for at least 2 weeks before symptoms develop.
How is Hepatitis A diagnosed?
A doctor may suspect you have Hepatitis A based on your physical exam and medical history (questions about your symptoms and where you have eaten or traveled). If your doctor thinks you are infected with the virus, you will have blood tests to find out whether your liver is inflamed and whether you have antibodies to the Hepatitis A virus. Antibodies indicate that you have been exposed to the virus.
How is Hepatitis A treated?
The infection is not treated with medication. Hepatitis A goes away on its own in most cases. Home treatment, such as eating balanced meals and drinking plenty of water, may help the body recover.
HAV infection does not cause long-term illness or chronic liver damage. More than 99% of people recover. However, in very rare cases a severe, rapidly progressing liver infection called fulminant hepatitis can occur. This may lead to an urgent need for liver transplantation. Fulminant hepatitis causes death in some people.
How can Hepatitis A be prevented?
You can prevent HAV infection by vaccination (Havrix or VAQTA), which is given in a series of two shots. The vaccine usually is 100% effective if you receive both shots before you are exposed to HAV.
A new vaccine (Twinrix) given in a series of three shots is available to prevent infection with both Hepatitis A and Hepatitis B . However, this vaccine should not be given to children under 18. It should be given only when absolutely necessary to pregnant or breast-feeding women because the vaccine's effect in the fetus or newborn is not known.
In addition, you can prevent Hepatitis A infection by avoiding:
Food that has been prepared by someone who is infected with HAV and who has poor hygiene.
Raw or undercooked shellfish (such as oysters, clams, or mollusks).
Uncooked food or tap or well water while traveling in foreign countries where Hepatitis A is common.
If an outbreak of HAV infection does occur, people who were exposed to the virus should receive a shot of immune globulin (IG) . If you get the shot within 2 weeks of exposure, you probably will not develop symptoms of HAV infection.
You can be infected with HAV only once. After that, you develop lifelong immunity to the virus and cannot become infected again.
