A-Z Index × Submit A-Z Index × Submit A-Z Index Search Dropdown × Submit Facebook Twitter LinkedIn Syndicate Emerging Infectious Disease journal ISSN: 1080-6059 Disclaimer: Early release articles are not considered as final versions. Any changes will be reflected in the online version in the month the article is officially released.
Rat hepatitis E virus (rHEV) is a zoonotic pathogen responsible for acute or chronic hepatitis in humans. To assess rHEV circulation in brown rats ( Rattus norvegicus ) in France, we sampled animals in 8 cities. We detected rHEV RNA in livers of 209/686 rats, a 30.5% positivity rate (95% CI 27.1%–34.0%). We found rHEV-positive animals in all 8 cities; positivity rate range was 9.7% (95% CI 6.7%–13.8%) to 44% (95% CI 33.9%–55.3%). Positivity rate differed by weight class: 9% (95% CI 5.8%–13.8%) in rats <100 g and 40.7% (95% CI 36.3%–45.2%) in rats > 100 g. We detected rHEV antibodies in 144/317 (45% [95% CI 40.0%–51.0%]) of the samples. We obtained 20 full genome sequences with distinct rHEV strains. We observed high genetic identity between rat and human sequences in France and Europe. rHEV appears to be enzootic in rat populations in cities in France.
Hepatitis E virus (HEV) is responsible for enterically acquired hepatitis in humans. The disease is frequently acute and self-limiting, but it can evolve to fulminant hepatitis or cause chronic hepatitis occurring primarily in immunocompromised persons ( 1 ). HEV belongs to the Hepeviridae family and Orthohepevirinae subfamily that comprise 4 genera, including Paslahepevirus and Rocahepevirus genera that infect humans. Most human cases are attributed to the species P. balayani ( 2 ). The genus Rocahepevirus includes Rocahepevirus ratti , formerly genotype C1 rat HEV (rHEV), which was identified in Rattus norvegicus rats in Germany in 2010 ( 3 ). It is phylogenetically distinct from other HEV viruses, sharing »60% sequence identity with Paslahepevirus . Since 2010, studies performed in Europe, Asia, Canada, and the United States in several rat species ( R. norvegicus , R. rattus , and others) have shown rHEV genomic positivity rates of 2.6%–26% ( 4 – 10 ). In France, 2 studies conducted in Lyon during 2010–2012 reported a rHEV genomic positivity rate of 14% ( 11 , 12 ) in R. norvegicus rats.
In 2018, rHEV was identified in humans as the cause of persistent hepatitis in a liver transplant recipient in Hong Kong ( 13 ). Additional cases of rHEV hepatitis were reported in both immunocompetent and immunocompromised patients from Asia, North America (after infection in Central Africa), and Europe ( 14 ). In France, 2 human cases of rHEV infections have been described, but no direct contact with rats was documented ( 15 , 16 ).
Rats (including the species R. norvegicus and R. rattus ) are the main reservoirs of rHEV; direct or indirect contact with them could be a potential risk for exposure. Spatiotemporal data and high genetic identity between rHEV sequences from rats and humans suggest zoonotic transmission ( 17 , 18 ). Although rats are the primary reservoir, rHEV has been detected sporadically in other animal species such as pigs ( 19 , 20 ).
Sequences of rHEV obtained from different geographic areas show a high degree of genetic variability. rHEV can be classified into multiple evolutionary groups (G1–G6); human strains are distributed across multiple phylogenetic groups ( 21 ). Within a country, genetic diversity of rat rHEV sequences can be high ( 9 ).…