Hepatitis A
Causes
Hepatitis A is a liver disease caused by hepatitis A virus.
Hepatitis A virus is spread from person to person by putting something in the
mouth that has been contaminated with the stool of a person with hepatitis A.
This type of transmission is called "fecal-oral."
For this reason, the virus is more easily spread in areas where there are poor
sanitary conditions or where good personal hygiene is not observed.
The following map gives prevalence rates of hepatitis A:
Symptoms
Persons with hepatitis A virus infection may not have any signs or symptoms of
the disease. Older persons are more likely to have symptoms than children.
If symptoms are present, they usually occur abruptly and may include fever,
tiredness, loss of appetite, nausea, abdominal discomfort, dark urine, and
jaundice (yellowing of the skin and eyes).
The average incubation period for hepatitis A is 28 days (range: 15–50 days).
A blood test (IgM anti-HAV) is needed to diagnose hepatitis A.
Duration
Symptoms usually last less than 2 months; a few persons are ill for as
long as 6 months.
Contagiousness
Casual contact, as in the usual office, factory, or school setting, does not
spread the virus.
Prevention
Two products are used to prevent hepatitis A virus infection:
immune globulin and hepatitis A vaccine.
Immune globulin is a preparation of antibodies that can be given before
exposure for short-term protection against hepatitis A and for persons who
have already been exposed to hepatitis A virus.
The vaccines currently licensed in the United States are HAVRIX and VAQTA.
Protection against hepatitis A begins four weeks after the first dose of
vaccine.
Protection will last for at least 20 years.
Immune globulin must be given within 2 weeks after exposure to hepatitis A
virus for maximum protection.
A single dose of immune globulin (0.02 mL/kg), which provides effective
protection against hepatitis A for up to 3 months.
Note that immune globulin is in short supply.
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Hepatitis B
Causes
Hepatitis B can affect anyone. Each year in the United States, more than
200,000 people of all ages get hepatitis B and close to 5,000 die of sickness caused by HBV.
One out of 20 people in the United States will get hepatitis B some time during
their lives.
Your risk is also higher if your parents were born in Southeast Asia, Africa,
the Amazon Basin in South America, the Pacific Islands, and the Middle East.
You get hepatitis B by direct contact with the blood or body fluids of an
infected person; for example, you can become infected by having sex or sharing
needles with an infected person.
Symptoms
Eyes or skin may turn yellow, lose appetite, have nausea, vomiting, fever, stomach or joint pain, feel extremely tired.
Contagiousness
Hepatitis B is not spread through food or water or by casual contact.
Sometimes, people who are infected with HBV never recover fully from the
infection; they carry the virus and can infect others for the rest of their
lives. In the United States, about one million people carry HBV.
You may have hepatitis B (and be spreading the disease) and not know it;
sometimes a person with HBV infection has no symptoms at all.
Precautions
Avoid sex and drugs and you will not get it.
Prevention
Hepatitis B vaccine is the best protection against HBV.
Three doses are needed for complete protection.
Treatment
There is no cure for hepatitis B; this is why prevention is so important.
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