Hepatitis A
Basics
Hepatitis A is an infectious viral illness that attacks the liver.
Worldwide, hepatitis A outbreaks often occur in epidemics, meaning that multiple people will catch the disease at the same time at the same location. Sporadic or isolated cases also crop up, however. In the U.S., there are outbreaks of hepatitis about every 10 years, and the number of reported cases can reach 35,000. There is a smaller number of cases yearly in between outbreaks.
The hepatitis A virus is the most common cause of acute viral hepatitis.
Several other viruses also cause hepatitis—hepatitis B, C, D, and E. All of them cause liver disease in one form or another, but hepatitis A is the variety that most often causes sudden liver inflammation (acute hepatitis). Hepatitis A is much less likely than the other varieties to become a long-term (chronic) condition.
Most people recover from hepatitis A without any lasting problems.
Causes
Hepatitis A is easily passed from person to person.
People who have contracted hepatitis A do not have symptoms for up to 40 days, but during that time they shed the virus in their stool. If they then improperly prepare food or fail to wash their hands, the virus can be passed on by what is called fecal-oral transmission. This is why daycare centers, where diapers are handled, are a frequent source of hepatitis A outbreaks.
Other sources of infection are household contacts or sexual activity; contacts made during international travel; and food or water that has been contaminated. In many cases, however, the initial source of the infection cannot be determined. Casual contacts, such as those at work or school, do not usually spread hepatitis A.
Symptoms
People with hepatitis A may develop symptoms of liver damage that come on quickly.
The symptoms of acute hepatitis are related to the invasion of liver cells by the virus, causing inflammation and disruption of the organ’s vital functions. They include the following:
The symptoms tend to clear up unaided within 8 weeks after infection.
Initially, symptoms of hepatitis usually appear within about 28 days. The onset is typically sudden, with fever, headache, and nausea appearing first, followed in several days by dark urine and jaundice (if these symptoms appear at all). The disease is more severe in the elderly and in those who already have some type of chronic liver disease, such as hepatitis B or hepatitis C.
Not all people will have symptoms; only about 70% of adults and 30% of children show signs of the disease. Most people do not need to be hospitalized for hepatitis A, and the disease normally resolves in about three to six months.
In rare cases, people may experience a variety of hepatitis A called cholestatic hepatitis A.
Cholestatic hepatitis A has a longer course (several months), and will almost always cause severe itching and jaundice. In very rare cases, hepatitis A can worsen rapidly and become life-threatening. In these cases, patients become drowsy or confused. If you have hepatitis A and experience these symptoms, get immediate medical attention.
In some cases, people can relapse.
Relapsing hepatitis A is uncommon, but it does occur. Someone who relapses will have two or more episodes of acute hepatitis during a 6- to-10-week period, with a period of time in between when they are free of symptoms.
Risk Factors
People traveling in parts of the world where hepatitis A is common are more likely to become ill.
South and Central America, Africa, Asia, India, and the Middle East all have relatively high rates of the disease.
People living in communities where there is a higher rate of hepatitis A have a greater risk of catching the disease.
In the U.S., Alaskan native villages and Native American reservations have high rates of hepatitis A when compared to the population average.
Men who have sex with other men are more likely to contract hepatitis A.
Intravenous (IV) drug use is a risk factor for hepatitis A.
This is particularly true because IV drug users have high rates of hepatitis C. The chronic liver damage caused by hepatitis C can make acute hepatitis more severe.
In some instances, people with bleeding disorders who take clotting factor concentrates to control their bleeding may be at greater risk for hepatitis A.
Some occupations carry a higher risk for hepatitis A. These include laboratory technicians and scientists who work with the virus itself; and scientists or workers who handle primates.
Diagnosis
Hepatitis A is an infectious viral illness that attacks the liver.
Worldwide, hepatitis A outbreaks often occur in epidemics, meaning that multiple people will catch the disease at the same time at the same location. Sporadic or isolated cases also crop up, however. In the U.S., there are outbreaks of hepatitis about every 10 years, and the number of reported cases can reach 35,000. There is a smaller number of cases yearly in between outbreaks.
The hepatitis A virus is the most common cause of acute viral hepatitis.
Several other viruses also cause hepatitis—hepatitis B, C, D, and E. All of them cause liver disease in one form or another, but hepatitis A is the variety that most often causes sudden liver inflammation (acute hepatitis). Hepatitis A is much less likely than the other varieties to become a long-term (chronic) condition.
Most people recover from hepatitis A without any lasting problems.
Hepatitis A is easily passed from person to person.
People who have contracted hepatitis A do not have symptoms for up to 40 days, but during that time they shed the virus in their stool. If they then improperly prepare food or fail to wash their hands, the virus can be passed on by what is called fecal-oral transmission. This is why daycare centers, where diapers are handled, are a frequent source of hepatitis A outbreaks.
Other sources of infection are household contacts or sexual activity; contacts made during international travel; and food or water that has been contaminated. In many cases, however, the initial source of the infection cannot be determined. Casual contacts, such as those at work or school, do not usually spread hepatitis A.
People with hepatitis A may develop symptoms of liver damage that come on quickly.
The symptoms of acute hepatitis are related to the invasion of liver cells by the virus, causing inflammation and disruption of the organ’s vital functions. They include the following:
The symptoms tend to clear up unaided within 8 weeks after infection.
Initially, symptoms of hepatitis usually appear within about 28 days. The onset is typically sudden, with fever, headache, and nausea appearing first, followed in several days by dark urine and jaundice (if these symptoms appear at all). The disease is more severe in the elderly and in those who already have some type of chronic liver disease, such as hepatitis B or hepatitis C.
Not all people will have symptoms; only about 70% of adults and 30% of children show signs of the disease. Most people do not need to be hospitalized for hepatitis A, and the disease normally resolves in about three to six months.
In rare cases, people may experience a variety of hepatitis A called cholestatic hepatitis A.
Cholestatic hepatitis A has a longer course (several months), and will almost always cause severe itching and jaundice. In very rare cases, hepatitis A can worsen rapidly and become life-threatening. In these cases, patients become drowsy or confused. If you have hepatitis A and experience these symptoms, get immediate medical attention.
In some cases, people can relapse.
Relapsing hepatitis A is uncommon, but it does occur. Someone who relapses will have two or more episodes of acute hepatitis during a 6- to-10-week period, with a period of time in between when they are free of symptoms.
People traveling in parts of the world where hepatitis A is common are more likely to become ill.
South and Central America, Africa, Asia, India, and the Middle East all have relatively high rates of the disease.
People living in communities where there is a higher rate of hepatitis A have a greater risk of catching the disease.
In the U.S., Alaskan native villages and Native American reservations have high rates of hepatitis A when compared to the population average.
Men who have sex with other men are more likely to contract hepatitis A.
Intravenous (IV) drug use is a risk factor for hepatitis A.
This is particularly true because IV drug users have high rates of hepatitis C. The chronic liver damage caused by hepatitis C can make acute hepatitis more severe.
In some instances, people with bleeding disorders who take clotting factor concentrates to control their bleeding may be at greater risk for hepatitis A.
Some occupations carry a higher risk for hepatitis A. These include laboratory technicians and scientists who work with the virus itself; and scientists or workers who handle primates.
Hepatitis A is diagnosed by a routine physical, medical history, and blood test.
The test requires drawing blood with a needle. A medical laboratory will then look for a protein called IgM anti-HAV, which is a type of antibody made by the body to combat the hepatitis A virus. Igm anti-HAV can be found in the body about one to two weeks after a person is exposed to the hepatitis A virus. It remains in the body for three to six months.
A combined active vaccination for both hepatitis A and hepatitis B is also available.
Re
Treatment
Uncommonly, complications of hepatitis A require hospitalization.
A small percentage of people will require hospitalization, usually for dehydration or complications of liver failure such as clotting problems or confusion. Fulminant hepatic failure, the worst-case scenario for hepatitis A, may require evaluation for liver transplant. Fulminant hepatic failure is a rare but rapidly progressive failure of the liver that can happen in serious cases of hepatitis. Signs of fulminant hepatitis are worsening jaundice, confusion, excessive sleepiness, and easy bruising or bleeding.
Bed rest and a good diet may be helpful in the early stages of recovery.
Some people experience nausea later in the day, so it may be best to eat a low-fat diet early in the day. In general, people are allowed to start their normal activities after they have the energy to do so, usually one to two months after the onset of the disease.
Avoid alcohol and other substances that can damage the liver.
Some common drugs, such as acetominophen, are toxic to the liver, if taken in high doses. If you are diagnosed with hepatitis A, you should consult with your doctor to be sure that any medications you are taking are not dangerous.
Your doctor is the best source of information on the drug treatment choices available to you.
People who have already had hepatitis A do not need to be vaccinated.
Infection and recovery from hepatitis A confers lifelong immunity. Because some people are infected by the virus but do not have classic symptoms, people who live in areas with a high rate of hepatitis A or those who are members of risk groups may want to have a blood test before they are vaccinated. If they have been exposed to the virus, there is no need for them to be vaccinated.
Post-exposure use of immunoglobulin is indicated for household or intimate contacts of the individual who has acute hepatitis A.
The prognosis for recovery from uncomplicated hepatitis A is very good.
For all ages, the death rate for hepatitis A is less than one percent. About 80% of those who have symptoms from hepatitis A recover fully in less than 8 weeks
Your doctor will schedule regular follow-up visits to help track the course of the infection.
Call your physician if you feel unusually poor, are having trouble concentrating or are really sleepy, or are suffering from easy bruising.