Co-circulation of Peste-des-Petits-Ruminants Virus Asian lineage IV with Lineage II in Nigeria

Abstract

Peste-des-petits-ruminants (PPR), a major small ruminant transboundary animal disease, is endemic in Nigeria. Strains of the causal agent, peste-des-petitsruminants virus (PPRV), have been differentiated into four genetically distinct lineages based on the partial sequence of the virus nucleoprotein (N) or fusion (F) genes. Peste-des-petits-ruminants virus strains that were identified initially in Africa were grouped into lineages I, II and III and viruses from Asia were classified as lineage IV and referred to as the Asian lineage. Many recent reports indicate that the Asian lineage is now also present in Africa. With this in mind, this study was conducted to reassess the epidemiology of PPRV in Nigeria. A total of 140 clinical samples from 16 sheep and 63 goats with symptoms suggestive of PPR were collected from different states of Nigeria during a four-year period (2010)(2011)(2012)(2013). They were analysed by the amplification of fragments of the N gene. Results for 33 (42%) animals were positive. The phylogenetic analysis of the N gene sequences with those available in GenBank showed that viruses that were detected belong to both lineage II and IV. Based on an analysis of the N gene sequences, the lineage IV isolates grouped into two clades, one being predominant in the north-eastern part of the country and the other found primarily in the southern regions of the country. This study reports the presence of PPRV Asian lineage IV in Nigeria for the first time.

First genetic characterization of Peste des Petits Ruminants from Niger: On the advancing front of the Asian virus lineage

“…The PPRV strains of lineage IV obtained in this study are genetically closely related to strains collected in the same year in north‐eastern Nigeria (Woma et al., ). In this cluster, the Nigerian isolates have a more basal position, suggesting that lineage IV entered Niger from north Nigeria at the latest in 2013.…”

“…A total of 12 of 14 samples collected in Maradi in 2013 were found to be positive, including two lung and lymph node samples and 10 ocular swabs (Table 1). The PPRV strains of lineage IV obtained in this study are genetically closely related to strains collected in the same year in north-eastern Nigeria (Woma et al, 2016). In this cluster, the Nigerian isolates have a more basal position, suggesting that lineage IV entered Niger from north Nigeria at the latest in 2013.…”

“…Equally interesting is the discovery of lineage IV in Niger in the samples collected in 2013, a lineage that was already detected in Cameroon in 1997 (Figure ). Its presence in Gabon (Maganga et al., ) and now its widespread distribution in Nigeria (Woma et al., ) and Niger indicate that this Asian lineage is spreading slowly in Africa in both a southwards and westwards direction. Taken together, all these results suggest the spread and progression of PPRV lineage IV from East and Central Africa into West Africa, where lineage II is currently predominant.…”

“…Since then, all surveys undertaken in different West African countries report the detection of PPRV strains belonging to lineage II (Baazizi et al., ; Banyard et al., ; Farougou, Gagara, & Mensah, ; Libeau et al., ; Mantip, Quan, Shamaki, & Van Vuuren, ; Salami et al., ). Moreover, recent studies reported the introduction of the PPRV lineage IV in Nigeria for the first time, suggesting that this lineage is expanding its range further into what was previously lineage II‐dominated West Africa (Mantip et al., ; Woma et al., ). Niger, situated north of Nigeria, is a country in which regular epizootic activities of PPR are known to occur like those in neighbouring countries.…”

First report and characterization of peste des petits ruminants virus in Liberia, West Africa

“…Although the PPRV from Sierra Leone is less related to Lib/2015 it is possible that different lineage II subclades are circulating in the country which may be more similar to Lib/2015; a situation that has recently been reported in Benin and Nigeria (Woma et al 2015;Adombi et al 2016). Therefore, in order to clarify the present PPR situation in Liberia, further similar studies should be carried out in neighbouring Guinea and Sierra Leone given the high cross-border movement of live animals for trade.…”