Therefore, epidemiological studies of people in various age groups and in children are also needed. Screening pregnant women for HEV is usually thus important for improving knowledge about the epidemiology (transmission and circulation) of this virus. These data provide evidence of a high prevalence of HEV in Gabon, providing indirect evidence of past contact with this virus. Findings Hepatitis E virus (HEV) is an enterically transmitted pathogen and is responsible for recent large-scale epidemics of hepatitis around the world, as reported recently in Uganda http://www.promedmail.org, where more than 7500 cases were registered in 1 year [1]. HEV induces self-limiting or acute hepatitis, and the severity can varied from no symptoms to fulminating contamination [2]. HEV infections have not been known to become chronic [2]; however, recently, persistent HEV contamination, with chronic hepatitis and cirrhosis, has been reported in patients with reduced immune surveillance induced by chemotherapy or post-transplant immune suppression [3,4]. The average mortality rate from HEV contamination is 1C4%, principally among adolescents and young adults, but it is still not clear that the severity is usually age-dependent. For unknown reasons, the mortality rate is usually higher among pregnant women, Azacyclonol especially during the third trimester [5]. In Sudan, a case:fatality ratio of 17.8% was found in an outbreak in Darfur, with a ratio of 31.1% among pregnant women [6]. In endemic areas, which include Africa, Asia and the Middle East, HEV outbreaks are waterborne, whereas in non-endemic areas such as Europe, Japan and the USA, sporadic cases of acute hepatitis are usually due to zoonotic foodborne transmission [7]. Bloodborne and perinatal transmission could also occur, but ingestion of fecally-contaminated water remains the main route of HEV transmission. Many HEV outbreaks have been observed in Africa, such as in Ethiopia and Somalia in 1988C1989, Djibouti in 1993, Morocco in 1994, Chad and Sudan in 2004C2005, the Democratic Republic of the Congo in 2006 and Uganda in 2007C2008 [1,8-12]. In the absence of outbreaks, the HEV prevalence in rural populations was 4.4% in Ghana, 14.0% in Burundi, 15.3% in South Africa and 67.7% in Egypt, with a seroprevalence of up to 84.3% among pregnant women [13-16]. There appear to be considerable differences in exposure to HEV in endemic areas. Few data are available around the circulation of HEV in central Africa. In 1995, no anti-HEV IgG was found in samples collected in Libreville, the capital of Gabon [17], but the study was based on a small sample and did not reflect the actual situation in the country. Furthermore, the laboratory techniques for HEV detection have advanced considerably since the time of that study. The aim of the study reported here was to evaluate the prevalence of anti-HEV IgG in samples collected from pregnant women Azacyclonol living in the five main cities of Gabon. We also compared the HEV prevalence in rural and urban areas in the region with the highest seroprevalence. Gabon is located around the Gulf of Guinea near the Equator, and tropical forest covers three quarters of the territory. To evaluate the HEV prevalence among pregnant women, two epidemiological surveys were conducted. The first was Azacyclonol conducted from January to March 2005, when blood samples were collected from all 840 pregnant women (mean age, 24.6 6.4 years; range, 14C44 years) who attended a first antenatal examination in the five main cities of the country: Libreville, the capital city in the north-west; Port-Gentil, the main harbor and economic capital in the west; Lambarn, in the centre of the country; Oyem in the north-east and Franceville in the south-east. The second study was conducted from January to June 2007 in rural and urban areas of Franceville, where the highest seroprevalence was found. The study obtained ethical clearance from the ethics committee; data on age and geographic origin were retained only after informed Azacyclonol consent had been obtained. To determine the anti-HEV IgG prevalence, we used Bnip3 the HEV (TMB) ELISA Kit (Genelabs Diagnostics, Singapore) according to the manufacturer’s instructions. Serological status Azacyclonol in relation to the age group and geographical origin of the pregnant women was analysed statistically by the chi-squared test with Yates correction, and.