Abstract:
Peste-des-petits-ruminants virus (PPRV) is a highly contagious, fatal and economically
important viral disease of small ruminants that is still endemic and militates against the
production of sheep and goats in endemic areas of the world. The aim of this study was to
describe the viral strains within the country. This was carried out by collecting tissue and swab
samples from sheep and goats in various agro-ecological zones of Nigeria. The phylogeny of
archived PPRV strains or isolates and those circulating and causing recent outbreaks was
determined by sequencing of the nucleoprotein (N)-gene. Twenty tissue and swab samples
from apparently healthy and sick sheep and goats were collected randomly from 18 states,
namely 3 states in each of the 6 agro-ecological zones visited. A total of 360 samples were
collected. A total of 35 samples of 360 (9.7%) tested positive by reverse transcriptase–polymerase
chain reaction, of which 25 were from oculo-nasal swabs and 10 were from tissue samples.
Neighbour-joining phylogenetic analysis using Phylogenetic Analysis Using Parsimony
(PAUP) identified four different lineages, that is, lineages I, II, III and IV. Interestingly, the
Nigerian strains described in this study grouped in two separate major lineages, that is,
lineages II and IV. Strains from Sokoto, Oyo, Plateau and Ondo states grouped according to the
historical distribution of PPRV together with the Nigerian 75/1 strain of lineage II, while other
strains from Sokoto, Oyo, Plateau, Akwa-Ibom, Adamawa, Kaduna, Lagos, Bauchi, Niger and
Kano states grouped together with the East African and Asian strains of lineage IV. This finding
confirms that both lineage II and IV strains of PPRV are circulating in Nigeria. Previously, only
strains of lineage II were found to be present in the country.
