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Hepatitis A

Definition

Hepatitis A is an inflammation of the liver caused by a virus, the hepatitis A virus (HAV). It varies in severity, running an acute course, generally starting within two to six weeks after contact with the virus, and lasting no longer than two or three months. HAV may occur in single cases after contact with an infected relative or sex partner. Alternately, epidemics may develop when food or drinking water is contaminated by the feces of an infected person.

Description

Hepatitis A was previously known as infectious hepatitis because it spread relatively easily from those infected to close household contacts. Once the infection ends, there is no lasting, chronic phase of illness. However it is not uncommon to have a second episode of symptoms about a month after the first; this is called a relapse, but it is not clear that the virus persists when symptoms recur. Both children and adults may be infected by HAV. Children are the chief victims, but very often have no more than a flu-like illness or no symptoms at all (so-called "subclinical" infection), whereas adults are far likelier to have more severe symptoms.

Epidemics of HAV infection can infect dozens and even hundreds (or, on rare occasions, thousands) of persons. In the public's mind, outbreaks of hepatitis A usually are linked with the eating of contaminated food at a restaurant. It is true that food-handlers, who may themselves have no symptoms, can start an alarming, widespread epidemic. Many types of food can be infected by sewage containing HAV, but shellfish, such as clams and oysters, are common culprits.

Apart from contaminated food and water, certain groups are at increased risk of getting infectious hepatitis:

Children at day care centers make up an estimated 14-40% of all cases of HAV infection in the United States. Changing diapers transmits infection through fecal-oral contact. Toys and other objects may remain contaminated for some time. Often a child without symptoms brings the infection home to siblings and parents.
Troops living under crowded conditions at military camps or in the field. During World War II there were an estimated five million cases in German soldiers and civilians.
Anyone living in heavily populated and squalid conditions, such as the very poor and those placed in refugee or prisoner-of-war camps.
Homosexual men are increasingly at risk of HAV infection from oral-anal sexual contact.
Travelers visiting an area where hepatitis A is common are at risk of becoming ill.

Causes and symptoms

The time from exposure to HAV and the onset of symptoms ranges from two to seven weeks and averages about a month. The virus is passed in the feces, especially late during this incubation period, before symptoms first appear. Infected persons are most contagious starting a week or so before symptoms develop, and remain so up until the time jaundice (yellowing of the skin) is noted.

Often the first symptoms to appear are fatigue, aching all over, nausea, and a loss of appetite. Those who like drinking coffee and smoking cigarettes may lose their taste for them. Mild fever is common; it seldom is higher than 101 °F (38.3 °C). The liver often enlarges, causing pain or tenderness in the right upper part of the abdomen. Jaundice then develops, typically lasting seven to ten days. Many patients do not visit the doctor until their skin turns yellow. As many as three out of four children have no symptoms of HAV infection, but about 85% of adults will have symptoms. Besides jaundice, the commonest are abdominal pain, loss of appetite, and feeling generally poorly.

Special situations

An occasional patient with hepatitis A will remain jaundiced for a month, two months or even longer, but eventually the jaundice will pass. Very rarely, a patient will develop such severe hepatitis that the liver fails. HAV infection causes about 100 deaths each year in the United States. In developed countries, a pregnant woman who contracts hepatitis A can be expected to do well although a different form of viral hepatitis (hepatitis E) can cause severe infection in pregnant women. In developing countries, however, the infection may prove fatal, probably because nutrition is not adequate.

Diagnosis

The early, flu-like symptoms and jaundice, as well as rapid recovery, suggest infectious hepatitis without special tests being done. If there is any question, a specialist in gastrointestinal disorders or infectious diseases can confirm the diagnosis—the detection of a specific antibody, called hepatitis A IgM antibody, that develops when HAV is present in the body. This test always registers positive when a patient has symptoms, and should continue to register positive for four to six months. However, hepatitis A IgM antibody will persist lifelong in the blood and is protective against reinfection.

Treatment

Once symptoms appear, no antibiotics or other medicines will shorten the course of infectious hepatitis. Patients should rest in bed as needed, take a healthy diet, and avoid drinking alcohol and/or any medications that could further damage the liver. If a patient feels well it is all right to return to school or work even if some jaundice remains.

Key terms

Antibody — A substance made by the body in response to a foreign body, such as a virus, which is able to attack and destroy the invading virus.

Contamination — The process by which an object or body part becomes exposed to an infectious agent such as a virus.

Epidemic — A situation where a large number of infections by a particular agent, such as a virus, develops in a short time. The agent is rapidly transmitted to many individuals.

Incubation period — The interval from initial exposure to an infectious agent, such as a virus, and the first symptoms of illness.

Jaundice — Yellowing of the skin (and whites of the eyes) when pigments normally eliminated by the liver collect in high amounts in the blood.

Vaccine — A substance prepared from a weakened or killed virus which, when injected, helps the body to form antibodies that will prevent infection by the natural virus.

Prognosis

Most patients with acute hepatitis, even when severe, begin feeling better in two to three weeks, and recover completely in four to eight weeks. After recovering from hepatitis A, a person no longer carries the virus and remains immune for life. In the United States, serious complications are infrequent and deaths are very rare. In the United States, as many as 75% of adults over 50 years of age will have blood test evidence of previous hepatitis A.

Prevention

The single best way to keep from spreading hepatitis A infection is to wash the hands carefully after using the toilet. Those who are infected should not share items that might carry infection. Special care should be taken to avoid transmitting infection to a sex partner. Travelers should avoid water and ice if unsure of their purity, or they can boil water for one minute before drinking it. All foods eaten should be packaged, well cooked or, in the case of fresh fruit, peeled.

If exposure is a possibility, infection may be prevented by an injection of a serum fraction containing antibody against HAV. This material, called immune serum globulin (ISG), is 90% protective even when injected after exposure—providing it is given within two weeks. Anyone living with an infected patient should receive ISG. For long-term protection, a killed virus hepatitis A vaccine became available in 1995. More than 95% of those vaccinated will develop an adequate amount of anti-HAV antibody. Those who should consider being vaccinated include healthcare professionals, those working at day care and similar facilities, frequent travelers to areas with poor sanitation, those with any form of chronic liver disease, and those who are very sexually active. Starting in 2000, routine immunization with the hepatitis A vaccine was recommended for children born in states where the rate of hepatitis A was two or more times the national average (Alaska, Arizona, California, Idaho, Nevada, New Mexico, Oklahoma, Oregon, South Dakota, Utah, and Washington) and suggested in states where the rate was 1.5 times the national average (Arkansas, Colorado, Missouri, Montana, Texas and Wyoming).

hepatitis /hep·a·ti·tis/ (hep″ah-ti´tis) pl. hepati´tides Inflammation of the liver.

hepatitis A a self-limited viral disease of worldwide distribution, usually transmitted by oral ingestion of infected material but sometimes transmitted parenterally; most cases are clinically inapparent or have mild flu-like symptoms; any jaundice is mild.

anicteric hepatitis viral hepatitis without jaundice.

hepatitis B an acute viral disease transmitted primarily parenterally, but also orally, by intimate personal contact, and from mother to neonate. Prodromal symptoms of fever, malaise, anorexia, nausea, and vomiting decline with the onset of clinical jaundice, angioedema, urticarial skin lesions, and arthritis. After 3 to 4 months most patients recover completely, but some may become carriers or remain ill chronically.

hepatitis C a viral disease caused by the hepatitis C virus, commonly occurring after transfusion or parenteral drug abuse; it frequently progresses to a chronic form that is usually asymptomatic but that may involve cirrhosis.

cholangiolitic hepatitis cholestatic h. (1).

cholestatic hepatitis

1. inflammation of the bile ducts of the liver associated with obstructive jaundice.

2. hepatic inflammation and cholestasis resulting from reaction to drugs such as estrogens or chlorpromazines.

hepatitis D , delta hepatitis infection with hepatitis D virus, occurring either simultaneously with or as a superinfection in hepatitis B, whose severity it may increase.

hepatitis E a type transmitted by the oral-fecal route, usually via contaminated water; chronic infection does not occur but acute infection may be fatal in pregnant women.

enterically transmitted non-A, non-B hepatitis (ET-NANB) h. E.

hepatitis G a post-transfusion disease caused by hepatitis G virus, ranging from asymptomatic infection to fulminant hepatitis.

infectious hepatitis h. A.

infectious necrotic hepatitis black disease.

lupoid hepatitis chronic active hepatitis with autoimmune manifestations.

neonatal hepatitis hepatitis of uncertain etiology occurring soon after birth and marked by prolonged persistent jaundice that may progress to cirrhosis.

non-A, non-B hepatitis a syndrome of acute viral hepatitis occurring without the serologic markers of hepatitis A or B, including hepatitis C and hepatitis E.

posttransfusion hepatitis viral hepatitis, now primarily hepatitis C, transmitted via transfusion of blood or blood products, especially multiple pooled donor products such as clotting factor concentrates.

serum hepatitis h. B.

transfusion hepatitis posttransfusion h.

viral hepatitis h. A, h. B, h. C, h. D, and h. E.

hepatitis A

A form of viral hepatitis caused by an enterovirus that does not persist in the blood serum, is transmitted by ingestion of infected food and water, and has a shorter incubation and milder symptoms than hepatitis B. Also called infectious hepatitis.

hepatitis A (HA),

a viral hepatitis caused by the hepatitis A virus (HAV), a picornovirus, characterized by slow onset of signs and symptoms. The virus may be spread through fecally contaminated food or water. The infection most often occurs in young adults and is usually followed by complete recovery. Disease duration is from 15 to 45 days. Relapses 6 to 12 months after the initial diagnosis are seen in 15% of the patients. Prophylaxis with immune globulin is effective in household and sexual contacts. A vaccine for immunization is available. Utilize standard precautions for diapered or incontinent patients. Also called acute infective hepatitis. See also viral hepatitis.

hepatitis A

Acute viral hepatitis A Hepatology An acute, rarely fatal infection by a picornavirus; globally, it is a common cause of morbidity; it is the mildest of viral hepatitis; ± 30% of the US population has been exposed Epidemiology Contaminated food–eg, shellfish, and other foods prepared by HAV carriers Clinical Fever, nonspecific GI malaise–eg, nausea, hepatosplenomegaly, jaundice, pruritus Clinical Duration 4-6 wks, followed by recovery; antibody formation protects against repeat infection Lab ↑ Liver enzymes–transaminases, dark urine due to ↑ BR; ↑ anti-HAV IgM and IgG antibodies; IgM–acute-phase antibody is detectable within days of onset and usually disappears in 6 wks; the IgG antibody is usually detected 5-6 wks post onset and is positive for life At-risk groups/factors Oral-fecal transmission–travelers, military personnel, institutionalized persons, day care center inmates, children & adolescents, Native Americans, raw shellfish, 'high-risk' sex Vaccine Formalin-inactivated hepatitis A vaccine is well tolerated; a single dose is effective against clinical HAV

Patient discussion about Hepatitis a antigens.

Q. Is there a vaccination against hepatitis? I want to volunteer in a charity organization abroad soon, and I heard that currently there’s and outbreak of hepatitis in the town I intend to go to. Is there anything I can do to prevent me from getting hepatitis? Is there a way to get a vaccination against it?

A. before you would like to go on with any vaccination, you should check out this very long list of links:

http://www.aegis.ch/neu/links.html

at the bottom you will also find links in english. vaccinations in general are very disputable/dubious and it is probably time that we learn about it.

Q. Is hepatitis a sexually transmitted disease? I mean hepatitis B and C mainly…

A. yes, hepatitis B is an STD, while hepatitis C is less likely caused by sexual transmitted disease.
hepatitis C usually transmitted through drugs usage and blood transfusion

Q. can the hepatitis b vaccination cause a soar throat?

A. yes it can be very probable!

before you would like to go on with any vaccination, you should check out this very long list of links:

http://www.aegis.ch/neu/links.html

at the bottom you will also find links in english. vaccinations in general are very disputable/dubious and it is probably time that we learn about it.

hepatitis A (redirected from Hepatitis a antigens)