HEV in pigs a ‘permanent zoonotic disease risk’
Hepatitis E virus circulates in domestic pigs and represents a “permanent zoonotic disease risk,” particularly among occupationally exposed individuals, according to a recent study performed in Hanoi, Vietnam.
“Hepatitis E virus (HEV) is the major cause of an enterically acquired acute hepatitis. Annually, an estimated 20 million novel human infections occur worldwide, leading to 3 million symptomatic cases and 56,000 hepatitis E-related deaths. HEV infection mainly affects people in East and South Asia, Africa and Latin America, in particular under conditions of poor sanitation and hygiene and restricted access to clean water and health services,” Nghiem Xuan Hoan, MD, PhD, of the Institute of Tropical Medicine at the University of Tübingen, Germany, and colleagues wrote. “Notably, 60% of cases and 65% of related deaths occur in Asia, where the seroprevalence of anti-HEV antibodies may exceed 25% in certain populations. In developed countries an increasing number of locally acquired human hepatitis E cases has been recognized.”
To assess HEV seroprevalence and risk, the researchers screened liver tissue samples from 210 domestic pigs and serum samples from 283 individuals who were occupationally exposed to pigs and pork meat — such as pork meat vendors, pig farmers and slaughterers — for HEV RNA. Their analysis also included 168 unexposed healthy controls.
Results of the study showed that HEV seroprevalence was higher among people occupationally exposed to pigs or pork meat compared with that of unexposed individuals — 11% vs. 6%, respectively. Additionally, positivity of anti-HEV immunoglobulin G was 66% among slaughterhouse staff, 51% among pig farmers and 38% among pork meat vendors, according to the study. Overall, researchers determined that 12.4% of pig liver tissues were positive for HEV RNA, specifically genotype 3.
“This study indicates a high prevalence of HEV infection in domestic pigs and individuals particularly exposed to pigs and pork meat, but also among the controls involved. Our study provides insight into HEV transmission dynamics and shows that domestic pigs may be an important zoonotic reservoir for HEV infection in Vietnam,” the authors concluded. “While information on HEV genotypes infecting humans is still scarce, we could infer that the genotypes HEV-3 and -4 may be the cause of acute sporadic hepatitis E, rather than other genotypes. Further studies on the occurrence of zoonotic hepatitis E in Vietnam are required.” – by Caitlyn Stulpin
Disclosures: The authors report no relevant financial disclosures.