Hepatitis A (Hep A) is very commonly found in the environment in developing countries with poor sanitation and hygiene. In these areas, the infection occurs in childhood which is usually very mild or asymptomatic and they develop long lasting immunity. Areas with low risk of infections are prone to epidemics related to contaminated food and water.
Hepatitis E (Hep E) is found most commonly in India, parts of Asia, Central America and Africa. Areas with economic turmoil such as warzones and refugee camps have witnessed epidemics primarily through contaminated water sources. Some strains of Hep E can be found in the environment in, circulating in animals like pigs and wild boars.
Both viruses are transmitted through the feco-oral route, through contaminated food and water. Upon entry into the body, the virus reaches the blood stream and reaches the liver to attack it. The incubation period, which is the time it takes from entry of the virus into the body till symptoms appear is roughly 2 – 8 weeks.
Hepatitis A can also be transmitted through close physical contact with an infected person, during sexual intercourse. IV drug users are also at increased risk as the virus can be transmitted through blood on shared needles.
Hepatitis E can be acquired through ingestion of undercooked meat from infected animals and through blood products. Mother to child transmission during pregnancy can also occur if the woman is acutely infected during pregnancy.
Not all infected individuals develop symptoms of illness. Some are asymptomatic and many might experience only a mild illness. The following symptoms are typically encountered in most patients
The clinical picture in the setting of an outbreak in the area suggests the diagnosis. The following tests are done to confirm the diagnosis and assess the severity of infection.
There is no specific drug or antiviral medication to treat Acute Viral Hepatitis due to Hep A and Hep E. The management is supportive
Acute Fulminant Hepatitis: In some individuals, the disease course can deteriorate with development of severe liver cell failure. These patients have the risk of hepatic encephalopathy from accumulation of ammonia in the body and bleeding abnormalities due to decreased production of clotting factors. Patients with underlying chronic hepatitis from Hep B or Hep C viruses and chronic liver disease are at an increased risk.
0.1-0.2% of patients with Hep A may progress to fulminant hepatitis. 1-2% of Hep E patients may develop it. In pregnant women with Hep E however, the risk of acute fulminant hepatitis rises to 10-20% putting the lives of both the mother and growing baby at risk.
Both conditions resolve completely, but take a few weeks to months before complete recovery. HepA can occasionally relapse and the person experiences symptoms a second time which is followed by full recovery.
These viruses do not remain in the body and there is no risk of chronic illness or carrier state. HepA and HepE are not associated with cancer of the Liver.
The best way to prevent infection from either virus is through good sanitation and hygiene practices. Handwashing while preparing meals and handling food, adequate cooking of food and proper sewage disposal drastically reduces risk of infection.
Hepatitis A can be effectively prevented by a vaccine carrying the inactivated virus. Two doses 6 months apart are recommended which provide nearly 100% protection from infection. The vaccine is recommended in those at high risk of infection. In case of an outbreak, vaccination within 2 weeks of exposure can successfully prevent infection.
A vaccine for HepE has been developed for use in China but is not available in other parts of the world.