What is hepatitis A? 
Hepatitis A (formerly known as infectious hepatitis) is a
liver disease caused by the hepatitis A virus (HAV). The disease is fairly common, but has declined significantly in recent years.
Who gets hepatitis A?
Antibodies produced during a previous infection with HAV, or in response to immunization for HAV, protect against infection. Anyone who has not been previously exposed to HAV or the immunization can become infected and ill from the hepatitis A virus.
How is the virus spread? 
The hepatitis A virus enters through the mouth, multiplies in the body, and is passed in the feces (stool). The virus can then be carried on an infected person's hands and can be spread by direct contact, or by consuming food or drink that has been handled by the individual. In some cases, it can be spread by sexual contact or by consuming water or food (e.g., raw shellfish, vegetables) contaminated by sewage.
What are the symptoms of hepatitis A?
The symptoms of hepatitis A may include tiredness, poor appetite, fever and nausea. Urine may become darker in color, and then jaundice (a yellowing of the skin and the whites of the eyes) may appear. The disease is rarely fatal and most people recover in a few weeks without any complications. Infants and young children tend to have very mild symptoms and are less likely to develop jaundice than are older children and adults. Not everyone who is infected will have all of the symptoms.
How soon after exposure do symptoms appear?
The symptoms may appear two to six weeks after exposure, but usually within four weeks.
How long is an infected person able to spread the virus?
The contagious period begins about two weeks before the symptoms appear. Most people are probably no longer contagious after the first week of jaundice. There is no carrier state.
Does past infection with hepatitis A make a person immune?
An individual who has recovered from hepatitis A is immune for life and does not continue to carry the virus.
What is the treatment for hepatitis A?
There are no special medicines or antibiotics that can be used to treat a person once the symptoms appear. Generally, bed rest is all that is needed for persons to recover from hepatitis A.
How can hepatitis A be prevented? 
The single most effective way to prevent spread is careful hand washing after using the toilet, changing diapers, or before eating or preparing food. Avoid eating raw shellfish taken from potentially contaminated waters. Also, infected people should not handle foods during the contagious period.
Disinfection of 'clean' surfaces with a 1:100 dilution of household bleach in water (i.e., 1/4 cup of 5.25% bleach in 1 gallon of water) or cleaning solutions containing quaternary ammonium and/or HCl (including concentrations found in many toilet cleaners) are effective in inactivating HAV.
The hepatitis A vaccine is effective at preventing infection with HAV. Close contacts of an infected person should call a doctor or the health department to determine if they should obtain a shot of vaccine or immune globulin (IG) to reduce their chance of becoming ill. Vaccine and/or IG may also be administered to persons traveling overseas to protect against hepatitis A infection.
Hepatitis A is inflammation of the liver caused by infection with the hepatitis A virus (HAV). Viruses are extremely small particles that cannot be seen by the naked eye. The hepatitis A virus is one of the smallest viruses and belongs to the viral family, Picornaviridae (‘Pico’ is Latin for ‘small’). Overall, the vast majority of people in the United States at any given time are not infected with HAV. In 2003 over 7,000 new infections were reported in the United States, and an additional 55,000 new infections may have occurred that were not reported. This is a fairly small number, considering that there are 300 million people living in the United States.
HAV continues to be one of the most frequently reported
vaccine-preventable diseases in the United States.
Anyone who is not immune to HAV can become infected after exposure to the virus. People who are already immune--either from previous infection or because they have been vaccinated against HAV--will not become infected. There is no lifelong (chronic) state of HAV.
Three out of ten people in the United States are already immune because of previous
exposure to HAV or vaccination against HAV.
HAV enters the body. HAV most commonly enters the body through ingestion (that is, eating or drinking a substance with HAV viral particles in it), and anyone who is susceptible (not yet
immune) to HAV will very likely become infected once the virus infects their system.
The viruses travel to the liver to reproduce (or replicate). This creates millions of viral copies. These new viruses are carried into the small intestine by bile made in the liver. The viruses then travel the entire course of the small and large intestine (about 20 feet!) and are shed in the stool when the infected person has a bowel movement. In order to get an HAV infection going, then, fecal material from a person infected with HAV must somehow make it into someone else’s mouth. That’s why the ‘route of transmission’ for HAV is called ‘oral-fecal’. You might not think this is likely--or even possible--to happen. But it is. For example, suppose an HAV-infected person prepares food at a restaurant. He or she might then use the restroom to have a bowel movement and neglect to wash the hands well enough to remove very small amounts of stool which remain on the fingers. This could leave tiny amounts of HAV-infected fecal material on the food worker’s hands which could make its way into the customer’s food. If the customer happens to eat that infected food and is not already immune, he will probably become infected by HAV and ill within 2-6 weeks. Another way to get HAV is by eating raw shellfish (such as oysters) which may have come from low-lying waters containing human feces from public dumping of sewage into otherwise fresh water. If some of that sewage has stool infected with HAV, and that stool makes its way into those oysters, then the virus can be carried by the oysters. Unless the oysters are cooked for at least one minute at 140 degrees, which kills the virus, the person eating them may get infected. Finally, certain sex practices involve direct contact with another person’s anus. For example, after anal sex a person might remove a condom and get HAV-infected fecal material on his hands. If that person were to touch his mouth, tiny amounts of stool and virus could be swallowed and start an infection. Mouth-to-anus contact is another way for tiny amounts of HAV-infected stool to enter a person’s mouth.
Remember that HAV is not normally found in human stool unless a susceptible
person has been exposed to Hepatitis A. Only then does the virus build up in the
liver and intestine, where it is eventually shed in the stool.
All of these groups below are at higher risk than average of ingesting human stool:
45% of those infected with hepatitis A have no known risk factors.
About 25% of those adults acutely (very recently) infected with HAV have no signs or
symptoms. However, the other 75% do have signs and symptoms.
Signs are clues to a patient’s condition which can be observed by a nurse or doctor, and
they include:
Symptoms are clues to a patient’s condition which the patient feels, but which cannot be
observed by a nurse or a doctor, and they include:
Two things to remember about the signs and symptoms of hepatitis A:
If you are reading this web page and think you might have Hepatitis A right now,
consult your primary healthcare provider for diagnosis and treatment options.
In most cases, people recover from the HAV illness within 4-6 weeks. Jaundice is almost always the last sign to disappear. So you may feel much better two or three weeks after becoming infected, but you may remain yellow for a few more weeks. In about 15 out of 100 HAV-infected people (15%), signs and symptoms can occur on and off again for close to nine months before the infection completely resolves (goes away permanently.)
A blood sample is all that is needed in order to perform the necessary tests for HBV.
Looks for acute HAV antibodies circulating in your blood. Antibodies are protein markers in the blood which tell you that at some point in the past your blood came into contact with HCV. It takes only 1-2 weeks for the HAV IgM antibodies to become detectable, and this time is called the window period. Before the antibodies are detectable, the IgM test will be “negative.” After the antibodies are detectable, the IgM test will be “positive,” indicating acute infection, and at this point you are able to pass the infection to others.
Looks for long-term HAV antibodies circulating in your blood. These antibodies tell if
you have ever had HAV or if you were ever vaccinated against HAV.
HAV is known as a ‘self-limiting’ disease. This means that treatment by a physician or hospital is not required too often. It is true that 11-22% of those acutely (very recently) infected with HAV require hospitalization. But usually this is only for intravenous rehydration (giving fluids through a vein because the stomach will not keep fluids down). And although it may be scary to experience the signs and symptoms of hepatitis A, most people require simple bed rest and taking in fluids and food as tolerated in order to recover.
You can become ill from acute hepatitis A only ONCE in your lifetime. After you are infected for the first time--whether you become ill or not--your body makes hepatitis A antibodies. These antibodies circulate in your blood for the rest of your life and will fight off the hepatitis A virus if you are ever again infected.
If you are ever infected with HAV you do not need the two-shot vaccination series to prevent HAV. The HAV antibodies left behind from previous infection will protect
you from becoming re-infected.
NO. There is no lifelong--or chronic--state of hepatitis A. Although 15% of people may experience illness for up to six months after the initial infection, after that HAV is expelled from the body and the protective antibodies prevent HAV infection from ever again occurring.
However, hepatitis B and hepatitis C DO have chronic states, and you may want to
read about that on the HBV and HCV web pages.
HAV is responsible for killing about 100 people every year in the United States.
Most of these people are adults over 50 years of age. These people usually die from
sudden liver failure within a month or so after infection. The likely reason these people
cannot fight off the HAV infection is that they already have some other disease which
limits or compromises their immune system and liver. So although HAV is not
considered to be a major killer disease, it can be lethal in some people.
The best way to avoid illness from HAV is to complete the two-shot vaccination
series against HAV (see HAV and HBV Vaccine Fact Sheet Link).
Very high rates of HAV are found in almost all countries on the continent of Africa,
and in many countries in South Asia.
There is an injectable substance called Hepatitis A Immune Globulin (see HAV and HBV Vaccine Fact Sheet Link.) Treatment with Hepatitis A Immune Globulin requires only one injection. It is like the vaccine only instead of getting it before you are exposed to HAV, you would get it after you have been exposed to HAV. So, if you recently had sexual contact with someone who you find out was ill with HAV at the time you had sex, you could consult a nurse or a doctor and explain to them your specific situation. At that time they would decide whether or not you should receive the Hepatitis A Immune Globulin.
If more than two weeks have passed since the time you think you might have been
exposed to the hepatitis A virus, Hepatitis A Immune Globulin will very likely not
work. At that point it is best to continue to be on the alert for signs and symptoms
which may or may not develop.
If a female becomes infected with HAV during pregnancy, she cannot pass on the virus to her unborn child. And it would be only in very rare circumstances that she could pass on the hepatitis A virus to her child during delivery. And although the hepatitis A vaccine is not considered dangerous to pregnant females or their offspring, most nurses and doctors prefer to wait until after pregnancy before giving the two-shot series.
You can also take the Hepatitis A Interactive Quiz
