Hepatitis E Virus in Manure and Its Removal by Psychrophilic anaerobic Biodigestion in Intensive Production Farms, Santa Catarina, Brazil, 2018–2019

Abstract

Hepatitis E virus (HEV) is an important enteric agent that can circulate in swine; it is excreted in manure, and of zoonotic interest. The present study investigated, by RT-qPCR, the circulation of HEV in swine manure from different types of pig farms (maternity, nursery, and grow-finish farms) in Santa Catarina State, the major pig production area of Brazil, and also evaluated the HEV removal efficiency of psychrophilic anaerobic biodigesters (PABs). While HEV was consistently detected in manure from grow-finish pig farms (>4 log HEV genome copies (GC) L−1), the virus was not detected in manure from maternity and nursery farms. These findings suggest a potential high biosafety status during primary-swine production, with a subsequent contamination in grow-finish production. The anaerobic biodigestion process reduced more than 2 log10 HEV GC in the processed swine manure. However, the virus concentration in final effluent remained high, with an average value of 3.85 log10 HEV GC L−1. Consequently, our results demonstrate that PABs can be a robust tool for effective inactivation of HEV, while reinforcing the need for sanitary surveillance and legislation of swine manure-derived biofertilizers, to avoid the spread of zoonotic enteric pathogens such as HEV.

Detection of Enteric Viruses and Core Microbiome Analysis in Artisanal Colonial Salami-Type Dry-Fermented Sausages from Santa Catarina, Brazil

“…However, HEV RNA was not detected in any of the 22 sausages from different production sites analyzed in this work. This contrasts with Souza et al [17], who detected HEV in effluent after swine manure digestion by psychrophilic anaerobic biodigesters (PABs) in Concórdia city, in Santa Catarina state. This demonstrates the circulation of HEV in the pig-finishing farms in the zone where the Colonial sausage we studied was produced.…”

“…Organs from naturally HEV-infected pigs were tested by García et al [14] and the HEV virus was not detected in loin samples: meat even from infected animals may therefore be only a low risk for HEV transmission. The main ingredient used in the preparation of Colonial salami is the loin, and this may explain the absence of HEV RNA from the samples tested, despite evidence of the circulation of HEV in pig farms in the region [17]. Other organs would need to be analyzed to assess the HEV contamination of the pigs in the region.…”

“…These viruses are excreted at high concentrations in animal stools (mainly from swine) so animal waste can contaminate water supplies, and when used in crops may contaminate food. Indeed, they persist as infectious particles in the environment, e.g., water and sewage, for several weeks at lower than body temperatures [13,[15][16][17]. HEV circulation has already been reported in humans and domestic swine in Brazil [17][18][19].…”

“…Indeed, they persist as infectious particles in the environment, e.g., water and sewage, for several weeks at lower than body temperatures [13,[15][16][17]. HEV circulation has already been reported in humans and domestic swine in Brazil [17][18][19].…”