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hepatitis A
hepatitis An. An acute viral hepatitis caused by an enterovirus that is transmitted by ingestion of infected food and water and that has a shorter incubation period and causes milder symptoms than hepatitis B. Also called infectious hepatitis.hepatitis A n (Pathology) a form of hepatitis caused by a virus transmitted in contaminated food or drink hepatitis A n. a normally minor form of hepatitis caused by an RNA virus that does not persist in the blood: usu. transmitted by ingestion of contaminated food or water. Also called infectious hepatitis. ThesaurusNoun | 1. | hepatitis A - an acute but benign form of viral hepatitis caused by an RNA virus that does not persist in the blood serum and is usually transmitted by ingesting food or drink that is contaminated with fecal matterinfectious hepatitisviral hepatitis - hepatitis caused by a virus | TranslationsEncyclopediaSeeHahepatitis A
Hepatitis A DefinitionHepatitis 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.DescriptionHepatitis 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 symptomsThe 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 situationsAn 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.DiagnosisThe 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.TreatmentOnce 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 termsAntibody — 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.PrognosisMost 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.PreventionThe 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).vi·ral hep·a·ti·tis type Aa viral disease with a short incubation period (usually 15-50 days), caused by hepatitis A virus, a member of the family Picornaviridae, often transmitted by fecal-oral route; may be inapparent, mild, severe, or occasionally fatal and occurs sporadically or in epidemics, commonly in school-age children and young adults; necrosis of periportal liver cells with lymphocytic and plasma cell infiltration is characteristic, and jaundice is a common symptom. Synonym(s): epidemic hepatitis, hepatitis A, infectious hepatitis, MS-1 hepatitis, short incubation hepatitis, virus A hepatitishepatitis An. An acute viral hepatitis caused by an enterovirus that is transmitted by ingestion of infected food and water and that has a shorter incubation period and causes milder symptoms than hepatitis B. Also called infectious 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 HAVvi·ral hep·a·ti·tis type A (vī'răl hep'ă-tī'tis tīp) A virus disease with a short incubation period (usually 15-50 days), caused by hepatitis A virus (family Picornaviridae, genus Hepatovirus) and often transmitted by the fecal-oral route; may be inapparent, mild, severe, or occasionally fatal, and occurs sporadically or in epidemics, commonly in school-age children and young adults; necrosis of periportal liver cells with lymphocytic and plasma cell infiltration is characteristic, and jaundice is a common symptom. Synonym(s): hepatitis A. hepatitis A Liver inflammation caused by the hepatitis A virus (HAV), which is excreted in the faeces and acquired by the ingestion of contaminated food. There is fever, severe loss of appetite, enlargement and tenderness of the liver, yellowing of the skin (JAUNDICE), darkening of the urine and pale, clay-like stools. There is no specific treatment but full recovery is the rule.Botkin, Sergei Petrovich, Russian physician, 1832-1889. Botkin disease - viral disease caused by poor hygienic conditions and ingestion of contaminated foods or liquids. Synonym(s): hepatitis Ahepatitis epidemicainfectious hepatitisPatient discussion about hepatitis AQ. 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 hepatitis be transferred from fathers sperm when concieving a child? My partner has hepatitis C and he has gotten me pregnant will our baby have it too?A. Here is taken from wikipedia (http://en.wikipedia.org/wiki/Hepatitis_C#Transmission) : Sexual transmission of HCV is considered to be rare. Studies show the risk of sexual transmission in heterosexual, monogamous relationships is extremely rare or even null. The CDC does not recommend the use of condoms between long-term monogamous discordant couples (where one partner is positive and the other is negative). However, because of the high prevalence of hepatitis C, this small risk may translate into a non-trivial number of cases transmitted by sexual routes. Vaginal penetrative sex is believed to have a lower risk of transmission than sexual practices that involve higher levels of trauma to anogenital mucosa. Mother-to-child transmission of hepatitis C has been well described, but occurs relatively infrequently. Transmission occurs only among women who are HCV RNA positive at the time of delivery; the risk of transmission in this setting is approximately 6 out of 100. Among women w More discussions about hepatitis AAcronymsSeeHep Ahepatitis A Related to hepatitis A: hepatitis ESynonyms for hepatitis Anoun an acute but benign form of viral hepatitis caused by an RNA virus that does not persist in the blood serum and is usually transmitted by ingesting food or drink that is contaminated with fecal matterSynonymsRelated Words |