HEV causes acute sporadic and epidemic viral hepatitis. Symptomatic HEV infection is most common in adults aged 15-40 years. Occasionally, a severe form of hepatitis develops, with mortality rates ranging between 0.5% - 4.0% of the overall population. This severe form of hepatitis may reach a mortality rate of 20% during pregnancy in the 3rd trimester.
HEV in blood donors
While HEV transmission usually occurs by eating and drinking contaminated food and water, blood transfusion is another route of infection.In a study conducted with 44,816 donor samples were collected in China between 2002 to 2008, the HEV seroprevalences in blood donors ranged from 29.9% to 41.7%. The rate of acute HEV infection was 0.43% to 1.51%. The viremia rates among the donors in 6 different regions of China ranged from 0.02% to 0.14%. These results also showed a high prevalence of viremia among anti-HEV IgM-positive samples. A total of 7.14% (30/420) of anti-HEV IgM-positive samples were RNA positive, but none of the IgM-negative samples were HEV RNA positive.
Recent seroprevalence studies indicate high prevalence of HEV infection among healthy populations in some industrial countries with historically low occurrence of Hepatitis E including the US, Japan and Europe.
Hepatitis E Vaccine : Hecolin®