Zoonotic viruses are thought to be the highest risk of epidemic diseases for next years. Among others,
these also include group A rotaviruses (RVA) and hepatitis E virus (HEV). RVA infection is preferentially speciesspecific,
and heterologous infections may also occur (animal-to-human virus transmission). Recently, a human RVA of
rabbit origin was described in a child, and a bovine-like RVA was isolated from a rabbit.
Hepatitis E is an emerging disease recognized as a zoonosis. Recently HEV was detected in both farmed and wild
rabbits in several countries. Risk of HEV zoonotic transmission from rabbits to humans is supported by experimental
infection of non-human primates and swine with rabbit HEV and by the detection of a rabbit related HEV strain in a
man.
During 2013, a total of 121 rabbits attending veterinary examination were enrolled in this study. Sera and
feces were collected from the same animal (except 7 fecal samples). Twenty-one samples were collected from studmare
rabbits. Sera were analyzed in Western blotting and Immunocytochemistry using as antigens: i. a baculovirus
expressed HEV capsid protein, ii. purified SA11 RV or iii. a crude extract of mock-infected Sf9. RNA was extracted
using Qiagen RNAEasy. RT-PCRs were performed using the OneStep RT-PCR (Qiagen).
None of the 135 fecal samples, showed presence of HEV genome. IgG against HEV were detected in 4/121 pet
rabbits tested. Rabbits showed no clinical signs of RVA infection. Twelve out of 52 sera recognized specific RVA
proteins. Twelve samples were positive in RT-PCR, one of which was confirmed through sequence analyses. One
animal was positive for both RVA and HEV IgG.
The seroprevalence to HEV in rabbits was low (3.3%); pets living in households have no contact with
other animals, implying that apossible HEV transmission through the fecal-oral route is reduced. Studying naturally
occurring heterologous rotaviruses may help understand how rotavirus cross the host-species barrier and enlighten the
molecular determinants that control host-species specificity and pathogenicity. Contact between pet rabbits and their owners might favor bi-directional animal-to-human transmission. Possible foodborne transmission of rabbit HEV
should also be evaluated
