Using a validated sensitive assay, we found hepatitis E virus (HEV) IgG in 52.5% of voluntary blood donors in southwestern France. This fi nding suggests HEV is highly endemic to this region. The high HEV prevalence may refl ect local dietary practices, such as eating uncooked pork and game products. It is now recognized that hepatitis E virus infection is not confi ned to developing countries. HEV infection is a growing public health concern in industrialized countries where the disease is mainly autochthonous, caused by HEV genotypes 3 (Europe) and 4 (People's Republic of China and Japan), and is thought to be zoonotic (1).In a previous study, we estimated that 16.6% of blood donors in the Midi-Pyrénées region of southwestern France have HEV antibodies (2). This rate was much higher than that measured in northern France (3), which suggests differences between these 2 populations and their exposure to HEV that we wished to explore further. However, it is diffi cult to make wider comparisons with seroprevalence studies from other areas because the various assays used differed in sensitivity and specifi city (4). Because a recent study suggested that the HEV IgG assay we used in our original study lacks sensitivity (5), we repeated and extended the study using a more sensitive assay that has been validated by using serum from PCR-proven HEV genotype 3 infections (5). The StudyDuring September 2003 through May 2004, serum samples were collected from 512 adult blood donors 18-64 years old (median 42 years) and 188 children 2-4 years old. The blood donors were unpaid voluntary donors; the children were hospitalized in Toulouse for surgery or trauma. All were residents of the Midi-Pyrénées region. The prevalence of HEV IgG was determined by using the Wantai HEV IgG enzyme immunoassay (Wantai Biologic Pharmacy Enterprise, Beijing, People's Republic of China), according to the manufacturer's instructions. Details of baseline demographic data and putative risk factors were collected from blood donors by using a structured questionnaire. In addition, to assess the risk for foodborne infection, we tested 18 local pig-liver sausages for HEV RNA using a quantitative real-time PCR based on the open reading frame 2 region of the HEV genome (6).HEV IgG was detected in 268 (52.5%) of 512 (95% confi dence interval [CI] 48.2%-56.8%) of the blood donors. Seroprevalence increased with age ( Figure 1). The ranges of optical density/cutoff ratios for positive and negative samples showed a clear bimodal distribution (Figure 2). Of 244 rural donors, 63.1% (95% CI 57%-69.2%) were anti-HEV positive compared with 42.9% (95% CI 37-48.8) of 268 urban donors (p<0.01). For children, seroprevalence was 3.7% (95% CI 1.0%-6.5%). The mean ± SD optical density/cutoff ratio of the positive samples was 5.43 ± 3.93 for children and 5.99 ± 3.52 for adults. Although several factors were associated with the presence of HEV IgG after univariate analysis, multivariate analysis identifi ed only age, rural residence, hunting, and contact with cats as factor...

Cases of autochthonous acute hepatitis E occur in most industrialized countries and are frequent in the South West of France. The prevalence of anti-hepatitis E virus (HEV) IgG antibodies in blood donors in this area was determined. A total of 529 samples from rural and urban blood donors were tested. The overall prevalence was 16.6%, 19.1% of rural donors and 14.2% of urban donors had anti-HEV antibodies (P = 0.13). The antibodies were widely distributed among all age groups and the sex ratio of the anti-HEV positive blood donors was 1.12 (P = 0.57). Hunting was the only pastime or profession associated with a high prevalence of anti-HEV antibodies (P = 0.038). The frequency of anti-HEV antibodies in blood donors could reflect active autochthonous transmission in this area of France. As the risk factors for HEV infection in industrialized countries are still unknown, further studies are needed to clarify the epidemiology of HEV infection in the Midi-Pyrénées region.

The apparent seroprevalence of hepatitis E Virus (HEV) varies greatly among developed countries depending on the geographical area and the sensitivity of immunoassays. We used a validated assay to determine the prevalence of HEV IgG and IgM antibodies among 3,353 blood donors living in southern France, who gave blood during the two first weeks of October 2011 and participated in the study. Demographic and epidemiological information was collected using a specific questionnaire. We also screened 591 samples for HEV RNA. Overall IgG seroprevalence was 39.1% and varied from 20% to 71.3% depending on the geographical area (p < 0.001) while IgM seroprevalence was 3.31%. Anti-HEV IgG was significantly correlated with increasing age (p < 0.001), eating uncooked pork liver sausages (p < 0.001), offal (p = 0.003), or mussels (p = 0.02). Anti-HEV IgM was associated with being male (p = 0.01) and eating uncooked pork liver sausages (p = 0.02). HEV RNA was detected in one of the 99 anti-HEV IgM-positive samples, but in none of the 492 anti-HEV IgM-negative samples. HEV is hyperendemic in southern France. Dietary and culinary habits alone cannot explain the epidemiology of HEV in this region, indicating that other modes of contamination should be investigated.

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