Long‐term shedding of hepatitis E virus in the feces of pigs infected naturally, born to sows with and without maternal antibodies

Abstract

Pigs are presumed reservoirs for hepatitis E virus (HEV) transmission to humans. To examine infection kinetics, two litters of domestic pigs (A and B, each containing 10 piglets) infected naturally with HEV were studied until pigs were 6 months old. Maternal IgG and IgA antibodies were detected in litter A piglets, but not in litter B ones. All pigs shed HEV in feces when they were 30-110 days old, and 17 developed viremia at 40-100 days of age. Phylogenetic analysis revealed a highly close sequence of HEV genotype 3 in all pigs. The serum levels of specific IgG and IgA were similar in all pigs, although IgA was not detected in the feces. Interestingly, the onset of both viremia and seroconversion was delayed significantly in litter A pigs. The kinetics of fecal virus shedding was similar in both litters; shedding was not detected after the pigs were 120 days old. The differences in the infection kinetics between litters A and B suggested that maternal antibodies delayed the onset of viremia and seroconversion. Quantitative real-time reverse transcriptase-polymerase chain reaction revealed that HEV RNA in feces peaked 10 days after initial shedding of approximately 10(6.0) copies/g. The viral load was much lower in the serum than in the feces. At 200 days of age, HEV RNA was found in the internal organs of 3 out of 13 pigs. These study findings improve the understanding of the dynamics of natural HEV transmission in pigs, which could help in controlling virus transmission from pigs to humans.

Chronic hepatitis E infection in children with liver transplantation

“…However, detection of the viral genome by PCR is technically challenging. Indeed, even in investigations on farm-raised animals (such as swine) where HEV infection is widespread, the threshold of HEV RNA detection is around 10 3 to 10 4 copies per ml of serum or per gram of faeces 28 29. Manipulation of blood samples, conditions of serum conservation for many years in some cases, and repeated freeze-thaw cycles of samples, are possible causes of HEV RNA degradation.…”

Host Immune Status and Response to Hepatitis E Virus Infection

“…2). HEV-3 is prevalent among swine worldwide (71)(72)(73)(74)(75)(76)(77)(78)(79)(80)(81)(82)(83)(84)(85)(86) as well as in other mammals, including deer and mongooses (83,(87)(88)(89), though little is known about the sylvatic circulation of HEV.…”

Temporal Changes in Environmental Health Risks and Socio-Psychological Status in Areas Affected by the 2011 Tsunami in Ishinomaki, Japan

“…Total RNA was extracted from sludge suspensions using QIAamp Viral RNA Kits (QIAGEN, Hilden, Germany). The HEV RNA of the 5′terminal region of ORF1 was detected by semi-nested RT-PCR (Kanai et al, 2009) using the One Step RT-PCR Kit (Qiagen). NLVs which belong to the Caliciviridae family are major causes of acute nonbacterial gastroenteritis and a major public health concern.…”