High Hepatitis E Virus Seroprevalence in Forestry Workers and in Wild Boars in France

Abstract

f Hepatitis E virus (HEV) is a fecally and orally transmitted human pathogen of worldwide distribution. In industrial countries, HEV is observed in an increasing number of autochthonous cases and is considered to be an emerging pathogen. A growing body of evidence suggests that HEV is a zoonotic disease, and pig handlers and pig veterinarians have been reported to be high-risk groups for HEV infection. The aims of the present study were to establish the prevalence of anti-HEV in wild boars in France and to identify whether forestry workers are at a higher risk of HEV infection. Three different anti-HEV tests were used to compare their effectiveness in detecting anti-HEV in the general population. The most sensitive test was then used to investigate HEV seroprevalence in 593 forestry workers and 421 wild boars. Anti-HEV was detected in 31% of the forestry workers and 14% of the wild boars. Detection of anti-HEV in humans was correlated with age, geographical location, and occupational activity and in wild boars was correlated with geographical location. HEV infection is frequent in woodcutters in France, and it varies geographically. Further studies are needed to confirm these findings and to elucidate the transmission route and the exact virus reservoirs.H epatitis E virus (HEV) is a nonenveloped, single-strand RNA virus that has been classified as the prototype and sole member in the Hepevirus genus of the Hepeviridae family (29). The viral genome of about 7.2 kb contains 3 partially overlapping open reading frames (ORFs). ORF1 encodes nonstructural viral proteins, ORF2 encodes the capsid protein, and ORF3 encodes a small multifunctional protein. Four major HEV genotypes belonging to a single serotype have been identified (11). Genotype 1 is detected in most cases of human HEV disease (waterborne epidemics and sporadic cases), genotype 2 is rare and has been found in several epidemics in Mexico and central Africa, and genotypes 3 and 4 are detected in swine and in autochthonous HEV infections in industrial countries (5,19,20,30,34,39,45,49).HEV is a significant fecally and orally transmitted human pathogen of worldwide distribution, causing self-limited disease with mortality rates of 1 to 3% in the general population and up to 20 to 25% in pregnant women. In developing countries, HEV outbreaks have been attributed to feces-contaminated water supplies. In industrial countries, HEV is observed in travelers returning from countries where HEV is endemic and in an increasing number of individuals with no history of traveling to regions where HEV is endemic, particularly in France (5, 6, 20). Molecular analysis of HEV strains has revealed that the strains identified in nonimported HEV cases form a group of genetically divergent isolates compared to HEV strains in regions where HEV is endemic (31, 39). The modes of transmission of sporadic nonimported cases and of autochthonous cases have rarely been determined, with the exception of zoonotic food-borne transmission from pigs, wild boars, and wild deer (19,25,40,41,4...

Seroprevalence in blood donors reveals widespread, multi-source exposure to hepatitis E virus, southern France, October 2011

“…The virus was detected in the livers of wild boar from the forests of the Ariège and Aude; these virus strains were very similar, genomically, to those isolated from patients suffering from hepatitis E (data not shown). It was demonstrated recently that wild boar from southern France are almost four times more likely to test positive for anti-HEV IgG than similar animals from northern France [21]. However, the present study does not associate the consumption of game meat with HEV seroprevalence after multivariate analysis.…”

A nationwide survey of hepatitis E viral infection in French blood donors

“…(33)(34)(35) We found drinking water to be another dietary factor linked to the presence of anti-HEV IgG. Drinking bottled water was associated with a low rate of IgG.…”

Preliminary study on the detection of hepatitis E virus (HEV) antibodies in pigs and wild boars in Poland

“…The time of sampling or the use of a different test could be the reason for the discordant results obtained by us and by Larska et al (9). Several studies have investigated the presence of HEV in wild boars in Italy, Germany, the Netherlands, and France (3,12,17,19). In Europe overall, the seroprevalence varies between 12% in the Netherlands (17) and 61.6% in Slovenia (7), with Spanish seroprevalence at 47.2% (5).…”

“…In conclusion, domestic pigs and wild boars may be a possible source of HEV infection for humans through direct contact, slaughtering, hunting, or consumption of food of animal origin (3,4,8). Therefore, regular and extensive surveillance of the occurrence of HEV in swine and wild boars should be performed in the future.…”