EditorialNovel strains of hepatitis E virus identified from humans and other animal species: is hepatitis E a zoonosis?
Section snippets
Animal Strains of HEV: Serological Evidence and Genetic Identification
It has been reported that anti-HEV was detected in pigs from developing countries such as Nepal (12), China (13) and Thailand (13) and from industrialized countries such as USA (9), Canada (13), Korea (13) Taiwan 14., 15. and Australia (16) Pina et al (11) also found that about 25% of pigs from Spanish herds are positive for anti-HEV, suggesting that HEV is also enzootic in pigs in Spain In addition to pigs, Kabrane-Lazizi et al (17) found that about 77% of the rats from Maryland, 90% from
Novel Strains of Human HEV: Where do. They Come From
Over the last couple of years, numerous genetically distinct strains of HEV have been identified from patients with acute hepatitis in both developing and industrialized countries. In USA, two cases of acute hepatitis E have been reported 23., 24.. The two USA isolates of HEV (US-1 and US-2) are genetically distinct from other known strains of HEV worldwide (about 80% amino acid sequence identity in ORF1) but are closely related to each other and to the USA strain of swine HEV (about 98% amino
Cross-species Infection of HEV: Is Hepatitis E a Zoonosis
It has been shown that swine HEV can cross species barriers and infect non-human primates and conversely, the US-2 strain of human HEV infects specific-pathogen-free (SPF) pigs. (10). The inoculated pigs rapidly became viremic and seroconverted to anti-HEV, suggesting that the US-2 strain is already competent to replicate in swine and may be of swine origin. A Central Asian strain of human HEV reportedly infects Russian domestic swine (33), although Meng et al. (34) were unable to infect SPF
Conclusion
In summary, the article by Pina et al. (11) has provided an impetus for further study of the natural history, epidemiology and pathogenesis of HEV. These recently identified novel strains of HEV may affect HEV vaccine development and diagnosis Although the experimental recombinant HEV vaccines appear to be effective 38., 39., their efficacy must be thoroughly evaluated for protection against these emerging strains of HEV. The current diagnostic assays may not be adequate for the many novel
Acknowledgements
The author's current research on HEV is supported by grants from the National Institutes of Health (AI01653-01, AI46505-01) I wish to thank Drs Robert H Purcell and Suzanne U Emerson in the Laboratory of Infectious Diseases at NIAID, NIH, and Dr Patrick G Halbur at Iowa State University for support and collaboration I would also like to thank Drs Thomas E Toth and Gholamreza Haqshenas for critical review of the manuscript, and Mr Denis Guenette for editorial assistance
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Hepatitis E outbreak in a mechanical factory in Qingdao City, China
2019, International Journal of Infectious DiseasesCitation Excerpt :In combination with the results of epidemiological investigation, it is therefore possible that this outbreak is an example of an HEV zoonotic transmission from swine to human. The first animal strain of HEV to be obtained from a pig was in the United States (Meng et al., 1997), with evidence that infection was transmitted zoonotically to humans (Meng, 2000). Results of the multivariate model and RNA genotyping indicated that pigs were a potential source for HEV infection in this outbreak and that HEV may be transmitted zoonotically to humans by eating undercooked pig liver.
Evidence of hepatitis E infection in swine and humans in the East Region of Romania
2014, International Journal of Infectious DiseasesCitation Excerpt :Hepatitis E has been diagnosed in industrialized countries, and it has been demonstrated that the genomic sequence of isolated HEV strains is most related to swine HEV prevalent in the swine population from the same region.2 The existence of a zoonotic reservoir has also been revealed, as the virus has been isolated from wild and domestic animals including swine, cattle, chickens, sheep, goats, and rodents.3,4 The first animal virus strain was isolated from a pig in the USA.5
Genetic heterogeneity and subtyping of human Hepatitis E virus isolates from Uruguay
2013, Virus ResearchCitation Excerpt :In developing countries, HEV infection is an important public-health concern because it causes large epidemics and waterborne outbreaks (Hino et al., 1991; Herrera, 1993; Donati et al., 1997). Over the last decade, an increasing number of autochthonous locally acquired cases have been reported in several industrialized countries and evidence of zoonotic transmission has been uncovered (Meng et al., 1997, 1998; Erker et al., 1999; Harrison, 1999; Meng, 2000; Okamoto et al., 2001; Smith, 2001; Nishizawa et al., 2003; Tei et al., 2003; Yazaki et al., 2003). HEV is unique among the known hepatitis viruses with animal reservoirs (swine, wild boar and deer) (Pavio et al., 2010).
Molecular detection and sequence analysis of hepatitis E virus in patients with viral hepatitis from North India
2011, Diagnostic Microbiology and Infectious DiseaseDetection of hepatitis E virus (HEV) from porcine livers in Southeastern Germany and high sequence homology to human HEV isolates
2011, Journal of Clinical VirologyCitation Excerpt :However, over the last years, studies have documented that hepatitis E infection also occurs among individuals in industrialized countries with no recent history of travel to previously known HEV endemic countries.9–11 In contrast to travel associated hepatitis E, zoonotic sources of HEV (genotypes 3 and 4) infection are suspected for autochthonous cases in industrialized countries.12 In Germany, HEV strains of genotypes 1, 3 and 4 have been isolated from patients with acute hepatitis E.13–16 In a recent case control study on HEV infection in Germany, consumption of offal (including porcine liver) and wild boar meat was independently associated with autochthonous HEV infection.16
Enteric Viral Hepatitis A and E
2011, Tropical Infectious Diseases: Principles, Pathogens and Practice