Frequent detection and characterization of hepatitis E virus variants in wild rats (Rattus rattus) in Indonesia

Abstract

One hundred sixteen rats (Rattus rattus) captured in Indonesia from 2011 to 2012 were investigated for the prevalence of hepatitis E virus (HEV)-specific antibodies and HEV RNA. Using an ELISA based on HEV genotype 4 with an ad hoc cutoff value of 0.500, 18.1 % of the rats tested positive for anti-HEV IgG. By nested RT-PCR, 14.7 % of the rats had rat HEV RNA, and none were positive for HEV genotype 1-4. A high HEV prevalence among rats was associated with lower sanitary conditions in areas with a high population density. Sixteen of the 17 HEV isolates obtained from infected rats showed>93.0 % nucleotide sequence identity within the 840-nucleotide ORF1-ORF2 sequence and were most closely related to a Vietnamese strain (85.9-87.9 % identity), while the remaining isolate differed from known rat HEV strains by 18.8-23.3 % and may belong to a novel lineage of rat HEV. These results suggest a wide distribution of rat HEV with divergent genomes.

High prevalence of rat hepatitis E virus in wild rats in China

“…Monitoring of the major species of wild rats might reflect the overall trend of rat HEV infection in wild rats. In this study we examined a total of 713 wild rat serum samples, and found that the HEV IgG-positive rates were 23.3%, similar to the rates recently reported for Vietnam, Germany and Indonesia (Johne et al, 2012;Li et al, 2011;Mulyanto et al, 2013). Furthermore, anti-rat HEV IgG antibody was detected not only in R. norvegicus rats but also in other species of wild rats, indicating that wild rats in China are commonly infected with rat HEV.…”

“…Human HEV is generally transmitted by the fecal-oral route, and our recent study (Li et al, 2013b) confirmed that rat HEV is also transmitted by that route. It was also reported that the seroprevalence of rat HEV is well correlated with sanitary conditions in Indonesia (Mulyanto et al, 2013). These observations suggest that the environmental hygiene influences rat HEV infection.…”

“…Since then, rat HEV strains have been detected from wild rats in the USA, Vietnam and Indonesia (Li et al, 2011;Mulyanto et al, 2013;Purcell et al, 2011), suggesting that rat HEV infection is widely distributed in wild rats around the world. The full-length genomes of rat HEV from Germany and Vietnam have been determined (Johne et al, 2012(Johne et al, , 2010a(Johne et al, , 2010bLi et al, 2013a), and partial sequences of rat HEV detected from USA and Indonesia have been reported (Mulyanto et al, 2013;Purcell et al, 2011). The nucleotide sequence identities between Germany rat HEV strains was 81.5-98.6% (Johne et al, 2012), and the full genome of the Vietnam rat HEV strain (V-105, GenBank accession no.…”

Serological evidence of infection with rodent-borne hepatitis E virus HEV-C1 or antigenically related virus in humans

“…Following that report, we and other groups have also found HEV-C1 in Vietnam, U.S.A., Indonesia, Denmark and China [10, 12, 13, 14, 17], suggesting a worldwide distribution of HEV-C1. HEV-C1 is genetically distant from human HEV: nucleotide sequence identity of entire genome is about 55%, and amino acid sequence identities of ORF1, ORF2 and ORF3 proteins are about 50%, 55% and 30%, respectively [4, 7].…”

Hepatitis E Virus

“…In further studies it was shown that comparable HEV sequences were detected in rats in the USA [133]. Phylogenetic sequence analysis of various rat isolates revealed that they have a high degree of variability, comparable to that of HEV-1 to HEV-4 [134]. Therefore it was suggested to group this rat HEV to the genus Orthohepevirus , species Orthohepevirus C (HEV-C1) or to the genus Rocavirus in the family of Hepeviridae (table 1) [14,15].…”