Molecular characterization of a porcine sapovirus strain isolated from a piglet with diarrhoea: a case report

Porcine sapoviruses, members of the family Caliciviridae, have been considered as an aetiological agent of gastroenteritis in pigs. In this study, we analysed 251 faecal samples obtained from 3 to 90 day-old diarrhoeic pigs in the Czech Republic between January 2005 and June 2010 and tested them by negative staining electron microscopy for the presence of sapoviruses. Only one sample showed the presence of viral particles with characteristic sapovirus morphology. The presence of sapovirus (SaV) was confirmed by an RT-PCR assay with primers specific for the sapoviral RNA polymerase and capsid genes. Phylogenetic analysis based on a partial sequence of the RNA polymerase gene placed the new Czech isolate into the GVII genogroup of porcine sapoviruses; however, analysis of a portion of the capsid gene sequence classified the isolate as GIII of the genus Sapovirus. These contradictory findings indicate that recombinant porcine sapovirus was identified. According to our knowledge this is the first description of porcine sapovirus in domestic pigs in the Czech Republic.