Circulation of Peste des Petits Ruminants Virus Lineage-IV Haplotypes in Pakistan: implication for Control and Eradication

Abstract

Peste des petits ruminants (PPR), a viral disease of small ruminants, was identified for the first time in Pakistan in 1991. Due to the availability of effective vaccine, FAO and OIE to set target of PPR control and eradication by 2030. The molecular signature of variation in the virus can assist in the control and eradication of a transboundary disease of PPR. In this study, the causative PPR virus was isolated in cell culture from suspected goats and sheep from Punjab, Pakistan. Out of swab samples, 74.2% produced cytopathic effect in cell culture and proceeded for amplification of nucleoprotein gene for genome based sequence comparison. Molecular typing showed that all of them belonged to the PPRV lineage IV. However, within lineage IV, haplotype variation was evident from the sequence analysis giving a clue of virus evolution over time in accordance with the route of disease spread. The isolated PPRVs being closely related to those from the neighboring countries of Dubai, Tajikistan and Iran. This subdivision indicates possible cross-border PPRV influx or efflux of PPRV strains through nomadism or trade from Northern areas (Tajikistan), across the south-western border of Taftan (Iran) and Dubai and other gulf countries. The study proposes joint effort by national and international animal health agencies to control and eradicate the transboundary disease of PPR in the region.