Identification of a porcine calicivirus related genetically to human sapoviruses

Department of Public Health and Zootecnic, University of Bari, Valenzano, Bari, Italy; Veterinary Medical Research Institute, Hungarian Academy of Sciences, Budapest, Hungary; Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio 44691, United States; Istituto Zooprofilattico Sperimentale di Lombardia/Emilia Romagna, Brescia – Italy; Istituto Superiore di Sanità – Dipartimento di Sanità Alimentare e Animale, Roma- Italy

^* To whom correspondence should be addressed. Email: v.martella{at}veterinaria.uniba.it.

	Abstract

Whether animals may act as calicivirus reservoirs for humans is unclear. By sequence analysis of a short fragment of the RNA-dependent RNA polymerase (RdRp) region, porcine sapovirus strains that genetically resemble human sapoviruses have been detected in piglets, but more informative sequences (capsid gene) were not available for a precise characterization. In this study, the 3'-terminus (the 3'-end of the ORF1, including the polymerase complex and the complete capsid, the ORF2 and the 3'-untranslated region) of one such human-like sapovirus strain, 43/06-18p3/2006/It, was determined, revealing that these viruses are more related genetically to human (47.4-54.9% aa) than to animal SaVs (35.2-44.7% aa) in the capsid gene. In addition, the recombination-prone RdRp-capsid junction region was highly conserved with that of human sapoviruses of genogroup GI. The presence of porcine viruses similar to human sapoviruses is a significant finding because of the potential for zoonotic infections or generation of porcine/human recombinants.