High genetic diversity and rapid spread of peste des petits ruminants virus Asian lineage IV in Nigeria

Peste des Petits Ruminants (PPR) is a highly contagious viral disease that mainly affects goats and sheep in Asia, Africa and the Middle East. The PPR virus (PPRV) can be classified into four genetically distinct lineages (I, II, III, and IV). All have been historically present in Africa, except the Asian lineage IV that has been spreading across the globe and Africa for the last decades. Previous studies have identified the presence of the lineage IV in Nigeria since 2010. In this study, samples were taken from 268 small ruminants with PPR symptoms across Nigeria in 2017-2018 to provide an update on the distribution and genetic diversity of the lineage IV in the country. Sequence from a portion of the PPRV nucleoprotein (N) gene could be obtained from 72 samples, and all but one belonged to lineage IV. Phylogenetic analysis identified at least 5 lineage IV sub-clusters in Nigeria, re-grouping samples across multiple regions. Our results suggest an extensive endemic circulation of PPRV lineage IV across Nigeria and across borders with neighbouring countries, highlighting the difficulty of the control of this disease in the region.