High frequency of hepatitis E virus infection in swine from South Brazil and close similarity to human HEV isolates

Abstract

Hepatitis E virus is responsible for acute and chronic liver infections worldwide. Swine hepatitis E virus has been isolated in Brazil, and a probable zoonotic transmission has been described, although data are still scarce. The aim of this study was to investigate the frequency of hepatitis E virus infection in pigs from a small-scale farm in the rural area of Paraná State, South Brazil. Fecal samples were collected from 170 pigs and screened for hepatitis E virus RNA using a duplex real-time RT-PCR targeting a highly conserved 70 nt long sequence within overlapping parts of ORF2 and ORF3 as well as a 113 nt sequence of ORF2. Positive samples with high viral loads were subjected to direct sequencing and phylogenetic analysis. hepatitis E virus RNA was detected in 34 (20.0%) of the 170 pigs following positive results in at least one set of screening real-time RT-PCR primers and probes. The swine hepatitis E virus strains clustered with the genotype hepatitis E virus-3b reference sequences in the phylogenetic analysis and showed close similarity to human hepatitis E virus isolates previously reported in Brazil.

Risk factors and seroprevalence of hepatitis E evaluated in frozen‐serum samples (2002‐2003) of pregnant women compared with female blood donors in a Southern region of Brazil

“…The study on pigs by Passos‐Castilho, performed in Paraná, showed a high prevalence of contamination of those animals, with 20% of positive HEV PCR. A phylogenetic analysis demonstrated HEV GT3 strains with close similarity to human HEV isolates that were previously reported in Brazil . An autochthonous case report identified a GT3 and sub‐GT3b infection in a male inhabitant with acute hepatitis E in Rio de Janeiro , where pigs were previously described as infected .…”

“…Phylogenetic analysis was performed in both, humans and animals (pigs), identifying the occurrence of HEV GT3 in Brazil, including the state of Paraná …”

Hepatitis E seroprevalence and associated factors in rural settlers in Central Brazil

“…A larger sample is possibly needed to identify statistical difference. Our results may be justified by the predominant circulation of HEV genotype 3 in Brazil 8,9 . However, besides the poor local sanitary and hygiene conditions, the epidemiological criteria to zoonotic HEV infection were not fully attended to.…”

“…Besides, very little is known about the seroepidemiology of HEV infection in rural residents in Brazil 3,7 , with just one study conducted on agricultural settlers in the Amazon Region 4 . Until recently, only HEV genotype 3 (zoonotic) has been reported in Brazil 8,9 . This study aimed to investigate the prevalence of HEV infection and associated factors in rural settlers in Central Brazil.…”

Challenges in research and management of hepatitis E virus infection in Cuba, Mexico, and Uruguay

“…HEV-G4 is almost exclusively restricted to Asia (3,4,7). HEV genotypes and reservoirs from nine LAC countries (Argentina, Bolivia, Brazil, Colombia, Costa Rica, Cuba, Mexico, Uruguay, Venezuela) (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) are shown in Table 1. Specific clinical manifestations of HEV infection have been tentatively associated with distinct genotypes; for example, HEV-G1 is related to fulminant acute hepatitis in pregnancy, whereas HEV-G3 is associated with chronic liver disease in immunosuppressed patients (2,7).…”