HEPATITIS A
What Is Hepatitis A?
Hepatitis A is one
of five known viruses that cause inflammation of the liver (the others
are B, C, D and E). The Centers For Disease Control and Prevention estimate
that 150,000 people in the U.S. are infected each year by hepatitis A,
a low rate compared to the rate in underdeveloped countries. The vast
majority of people recover from the infection within six months without
any serious health problems
How Is Hepatitis A Transmitted?
Transmission is usually
by drinking water or eating food that has been contaminated with fecal
matter containing the virus. Unlike the hepatitis
B and hepatitis C viruses, the hepatitis A virus
remains stable when liver cells secrete it into bile, which then enters
the digestive tract. Fecal matter from an infected person has a high concentration
of the virus during a certain period of infection, whereas saliva and other
bodily fluids have a low concentration. The virus can survive in this contaminated
fecal matter on a persons hand, for example, or on a surface for three
to four hours at normal room temperatures. Thus, an eating utensil contaminated
with the virus could be a way to transmit the infection to a person. Contaminated
shellfish are a frequent source of infection. Direct contact with an
infected person is another confirmed transmission route, as are kissing
on the mouth and anal sex. Contamination of needles used for intravenous
administration of drugs is a suspected route of transmission. In over 40%
of the reported cases it is not known how these people were infected.
Who Is At Risk For Hepatitis A?
The risk of being
infected with the hepatitis A virus generally depends on the hygienic
and sanitary conditions in an area. High risk geographic areas are
the Middle East, South America, Eastern Europe, Central America, Africa
and Southeast Asia. There are also areas in the United States where poor
sanitary conditions or hygiene have resulted in outbreaks of hepatitis
A. It is also after symptoms appear or two to three weeks before that patients
will shed the virus in high concentration in feces and thus they are most
infectious to others. The Centers for Disease Control and Prevention
(CDC) lists household or sexual contact, daycare attendance or employment
and recent international travel as the major known risk factors for the
transmission of hepatitis A. The CDC estimates that a third of the
U.S. population has been infected. Children at daycare centers spread
the virus because of fecal-oral contamination through diaper changing.
Outbreaks have been reported in the military, at institutions for the disabled
and because of infected restaurant workers. Those using injectable drugs
with contaminated needles have also been infected with the virus.
What Are The Symptoms For Hepatitis
A Infection?
As with the other
hepatitis viruses a person infected with hepatitis A may not have any symptoms.
However, in those who do have symptoms, they resemble the flu. These symptoms
include fatigue, nausea, vomiting, pain in the liver area, dark urine or
light colored stools and fever. Liver function tests are elevated,
with many adults developing jaundice. Children under two rarely have symptoms.
Most people recover within six months
Can Hepatitis A Result In Serious
Complications?
A very small percentage
of people infected with hepatitis A risk serious complications. These
include people with alcoholic hepatitis, chronic
hepatitis with cirrhosis or the elderly over 60 years old. These patients
may suffer liver failure after becoming infected with hepatitis A. Federal
mortality statistics for 1992 list hepatitis A as the primary cause of
death for 82 people. In 1993 an estimated 121 people were hospitalized
for hepatitis A. Patients with hepatitis A may show improvement in their
symptoms and liver function tests only to suffer a relapse, usually after
four weeks. A relapse can occur more than once and there is no way to predict
who will suffer a recurrence of acute symptoms. In rare cases, jaundice
lasts for two or more months. It is rare for pregnant women who are infected
with hepatitis A to suffer serious complications to themselves or their
newborn children.
How Is Hepatitis A Diagnosed ?
Hepatitis A is diagnosed
by a blood test that is positive for the antibody to the virus, which
appears about four weeks after the infection. There are no false positives
or negatives with this test. Liver function tests
(serum alanine aminotransferase [ALT] and asparate aminotransferase [AST])
are elevated above normal, often to very high levels. Symptoms will normally
appear during the first four weeks of infection.
How Is Hepatitis A Treated?
There is no specific
treatment for hepatitis A. Most patients are told to rest for one to
four weeks after a diagnosis is made, to avoid intimate contact and to
consume foods high in protein. People who have come into contact with the
patient should be given temporary immunization with immune serum globulin
(ISE), within two weeks of exposure.
What Is The Hepatitis A Vaccine?
The current vaccine
for hepatitis A in the U.S. is manufactured by SmithKline Beecham, Inc.
The vaccine is made from an inactive hepatitis A virus that has been suspended
in a sterile solution. It is not made from infected blood. The body
reacts with the inactive virus to produce an antibody that protects
against infection of the liver by the hepatitis A virus. Clinical trials
have shown that the vaccine is effective in preventing infection in over
90% of people who were exposed. There are generally no known side effects,
except for soreness at the site of the injection. Less than 10% of
those vaccinated become tired and nauseous. Children between one and
18 should receive two initial doses of the vaccine and a booster between
six and 12 months. Adults should receive an initial dose and then a booster
six to 12 months later. It takes at least two weeks before protection
is achieved. It is not certain how long protection will last.
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The American Liver Foundation is the only national voluntary health
organization dedicated to preventing, treating, and curing hepatitis and
all other liver and gallbladder diseases through research and education.
American Liver Foundation
1425 Pompton Avenue,
Cedar Grove, NJ 07009
1-800-223-0179
Copyright 1995
Please submit any questions or comments
to: Endoscopic Microsurgery
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