Hepatitis A
Hepatitis A is an infectious disease of the liver caused by Hepatovirus A (HAV);[6] it is a type of viral hepatitis.[7] Many cases have few or no symptoms, especially in the young.[1] The time between infection and symptoms, in those who develop them, is 2–6 weeks.[2] When symptoms occur, they typically last 8 weeks and may include nausea, vomiting, diarrhea, jaundice, fever, and abdominal pain.[1] Around 10–15% of people experience a recurrence of symptoms during the 6 months after the initial infection.[1] Acute liver failure may rarely occur, with this being more common in the elderly.[1]
Hepatitis A
Infectious hepatitis
2–6 weeks after infection[2]
8 weeks[1]
Blood tests[1]
Hepatitis A vaccine, hand washing, properly cooking food[1][3]
114 million symptomatic and nonsymptomatic (2015)[4]
11,200[5]
It is usually spread by eating food or drinking water contaminated with infected feces.[1] Undercooked or raw shellfish are relatively common sources.[8] It may also be spread through close contact with an infectious person.[1] While children often do not have symptoms when infected, they are still able to infect others.[1] After a single infection, a person is immune for the rest of their life.[9] Diagnosis requires blood testing, as the symptoms are similar to those of a number of other diseases.[1] It is one of five known hepatitis viruses: A, B, C, D, and E.
The hepatitis A vaccine is effective for prevention.[10][11][12]
[1][3] Some countries recommend it routinely for children and those at higher risk who have not previously been vaccinated.[1][13] It appears to be effective for life.[1] Other preventive measures include hand washing and properly cooking food.[1] No specific treatment is available, with rest and medications for nausea or diarrhea recommended on an as-needed basis.[1] Infections usually resolve completely and without ongoing liver disease.[1] Treatment of acute liver failure, if it occurs, is with liver transplantation.[1]
Globally, around 1.4 million symptomatic cases occur each year[1] and about 114 million infections (symptomatic and asymptomatic).[4] It is more common in regions of the world with poor sanitation and not enough safe water.[13] In the developing world, about 90% of children have been infected by age 10, thus are immune by adulthood.[13] It often occurs in outbreaks in moderately developed countries where children are not exposed when young and vaccination is not widespread.[13] Acute hepatitis A resulted in 11,200 deaths in 2015.[5] World Hepatitis Day occurs each year on July 28 to bring awareness to viral hepatitis.[13]
Prognosis[edit]
In the United States in 1991, the mortality rate for hepatitis A was estimated to be 0.015% for the general population, but ranged up to 1.8–2.1% for those aged 50 and over who were hospitalized with icteric hepatitis.[58] The risk of death from acute liver failure following HAV infection increases with age and when the person has underlying chronic liver disease.
Liver illness can be brought on by the hepatitis C virus, also known as Hep C or HCV. While the majority of kids and teenagers recover from the initial stage of HCV infection, 60–80% of them could show symptoms of a persistent liver infection. This may result in fatalities as well as far more severe liver issues. In the US, the hepatitis C virus is responsible for over 10,000 fatalities annually.
Young children who are infected with hepatitis A typically have a milder form of the disease, usually lasting 1–3 weeks, whereas adults tend to experience a much more severe form of the disease.[39]