Epidemiology of Hepatitis E in Low- and Middle-Income Countries of Asia and Africa

Abstract

Hepatitis E is an acute, viral hepatitis primarily transmitted through the fecal-oral route. The first major epidemic of hepatitis E virus (HEV) was reported in 1955 in Delhi, India. Since that time, numerous epidemics have been reported across the low- and middle-income countries in Asia and Africa. Even in the absence of large-scale outbreaks, hepatitis E is an important cause of clinical hepatitis. Serologic studies across Asia and Africa show a high prevalence of anti-HEV antibodies. Interest in hepatitis E has increased over the last two decades. However, there are many unanswered questions about the epidemiology of hepatitis E, including a low clinical illness rate in children and the high case fatality rate in pregnant women. Widespread usage of a hepatitis E vaccine may serve to relieve the burden of HEV disease in low- and middle-income countries in Africa and Asia.

First Report of Hepatitis E Virus Circulation in Domestic Pigs in Nigeria

“…1,23 In Nigeria, the husbandry systems practiced include intensive, semi-intensive, and extensive or free range farming 24 where pigs are either housed or allowed to roam freely to scavenge for food. In the free range system, pigs travel far in search of food and water.…”

“…1 Hepatitis E is the single most important cause of acute clinical hepatitis among adults throughout Central and Southeast Asia and the second most important cause throughout the Middle East and North Africa following hepatitis B.…”

Hepatitis E and Acute-on-Chronic Liver Failure

“…It causes large scale epidemics of AVH across the low-and middle income countries in Asia and Africa, and also causes sporadic cases of AVH in the same geographical region. 3,4 AVH due to HEV is usually an acute, self-limiting illness, similar in clinical presentation to AVH caused by hepatitis A virus (HAV). However, in two situations HEV may cause serious disease leading to high mortality: when AVH occurs in pregnant women which may rapidly worsen as acute liver failure, 5 and when AVH occurs in patients of chronic liver disease which may worsen as acute-on-chronic liver failure (ACLF).…”

Hepatitis-E-Virus

“…Retrospektive Untersuchungen eines Hepatitisausbruchs in den Jahren [1955][1956] in Delhi, Indien, zeigten, dass HEV kein neu auftretender Erreger ist, sondern seit langer Zeit zirkuliert [2]. In den folgenden Jahren wurden weitere durch HEV hervorgerufene Epidemien in Asien, Afrika und Mexiko beschrieben [3]. Den experimentellen Nachweis, dass neben HAV ein zweites fäkal-oral über-tragbares Virus eine Hepatitis verursacht, lieferten Übertragungsversuche von Balayan et al [4] und Chauhan et al [5].…”

“…Balayan et al [4] konnten aus dem Stuhl der infizierten Freiwilligen sphä-rische, 27-30 nm große, virus-ähnliche Partikel isolieren, die im CsCl-Gradienten eine Dichte von 1,35 g/cm 3 aufwiesen und auf Grund der Morphologie zur Familie der Caliciviridae eingruppiert wurden. Mit Hilfe der Immunelektronenmikroskopie unter Verwendung von Rekonvaleszentenseren konnten diese Partikel sowohl in der prä-(ab 27.…”