Hepatitis A
Hepatitis A, caused by infection with the Hepatitis A virus (HAV), has an incubation period of approximately 28 days (range: 15–50 days). HAV replicates in the liver and is shed in high concentrations in feces from 2 weeks before to 1 week after the onset of clinical illness. HAV infection produces a self-limited disease that does not result in chronic infection or chronic liver disease.
How is Hepatitis A is transmitted?
Person-to-person transmission through the fecal-oral route (i.e., ingestion of something that has been contaminated with the feces of an infected person) is the primary means of HAV transmission result from close personal contact with an infected household member or sex partner.
Common-source outbreaks and sporadic cases also can occur from exposure to fecally contaminated food or water. Uncooked Hep A contaminated foods have been recognized as a source of outbreaks. Cooked foods also can transmit HAV if the temperature during food preparation is inadequate to kill the virus or if food is contaminated after cooking, as occurs in outbreaks associated with infected food handlers. Waterborne outbreaks of Hep A can happen in under developed and developing countries with poorly maintained sanitation and water supplies.
Who is at increased risk for acquiring HAV infection?
- Travelers to countries with high or intermediate endemicity of HAV infection
- Homosexual partners, Users of injection and non-injection illegal drugs
- Persons with clotting factor disorders
- Contaminated salads,salad bars, contaminated meat and uncooked sea food
What are the signs and symptoms of HAV infection?
When symptoms are present, they usually occur abruptly and can include the following: Fever,Fatigue, Loss of appetite,NauseaVomitingAbdominal painDark urineClay-colored bowel movementsJoint painJaundice In children aged <6 years, 70% of infections are asymptomatic; if illness does occur, it is typically not accompanied by jaundice. Among older children and adults, infection is typically symptomatic, with jaundice occurring in >70% of patients.p
When symptoms occur, how long do they usually last?
Symptoms usually last less than 2 months, although 10%–15% of symptomatic persons have prolonged or relapsing disease for up to 6 months.
What is the incubation period for Hepatitis A?
The average incubation period for Hepatitis A is 28 days (range: 15–50 days).
How long does HAV survive outside the body? How can the virus be killed?
HAV can live outside the body for months, depending on the environmental conditions. The virus is killed by heating to 185 degrees F (85 degrees C) for one minute. However, the virus can still be spread from cooked food if it is contaminated after cooking.
Can Hepatitis A become chronic?
No. Hepatitis A does not become chronic.
Can persons become reinfected with HAV after recovering from Hepatitis A?
No. IgG antibodies to HAV, which appear early in the course of infection, provide lifelong protection against the disease.
How is HAV infection prevented?
Vaccination with the full, two-dose series of Hepatitis A vaccine is the best way to prevent HAV infection. Hepatitis A vaccine is available persons 12 months of age and older.
Good hygiene — including hand washing or use of hand sanitizer after using the bathroom, changing diapers, and before preparing or eating food — is also integral to Hepatitis A prevention, given that the virus is transmitted through the fecal–oral route.
Travelers to developing and underdeveloped countries strongly recommended to take vaccinations.