Persistence of the historical lineage I of West Africa against the ongoing spread of the Asian lineage of peste des petits ruminants virus

Abstract

Peste des petits ruminants (PPR) is a highly contagious disease of small ruminants. The causal agent, PPR virus (PPRV), is classified into four genetically distinct lineages. Lineage IV, originally from Asia, has shown a unique capacity to spread across Asia, the Middle East and Africa. Recent studies have reported its presence in two West African countries: Nigeria and Niger. Animals are frequently exchanged between Mali and Niger, which could allow the virus to enter and progress in Mali and to other West African countries. Here, PPRV samples were collected from sick goats between 2014 and 2017 in both Mali and in Senegal, on the border with Mali. Partial PPRV nucleoprotein gene was sequenced to identify the genetic lineage of the strains. Our results showed that lineage IV was present in south‐eastern Mali in 2017. This is currently the furthest West the lineage has been detected in West Africa. Surprisingly, we identified the persistence at least until 2014 of the supposedly extinct lineage I in two regions of Mali, Segou and Sikasso. Most PPRV sequences obtained in this study belonged to lineage II, which is dominant in West Africa. Phylogenetic analyses showed a close relationship between sequences obtained at the border between Senegal and Mali, supporting the hypothesis of an important movement of the virus between the two countries. Understanding the movement of animals between these countries, where the livestock trade is not fully controlled, is very important in the design of efficient control strategies to combat this devastating disease.

Ongoing Assessment of the Molecular Evolution of Peste Des Petits Ruminants Virus Continues to Question Viral Origins

“…Furthermore, the circulation of predominantly three PPRV lineages after 2013, following the apparent disappearance of lineage I, since 1989, may have aided the attainment of the maximum effective population. Interestingly, more recent reports, from regions not yet well studied, have demonstrated the ongoing circulation of lineage I in West Africa [4], although full genome analyses have not been available to enable the inclusion of this finding within evolutionary assessments. Future analysis of PPR across West Africa ruminant populations may yield further samples to enable a better evolutionary assessment of lineage I viruses.…”

“…PPR is caused by the infectious viral agent PPRV, which is a non-segmented negativestrand RNA virus that has been phylogenetically classified, initially by partial sequence analyses and later through full genome analysis, into four distinct genetic lineages (I−IV) [3]. Lineage I contains viruses from West Africa, with very few defined isolates that were believed to have become extinct; however, recent studies have suggested that lineage I PPRV persists in West Africa, despite the emergence of apparently more dominant lineages [4]. Lineage II is also of West African origin, with historic isolates being described from Nigeria and Benin, with more contemporary detections also being from West Africa.…”

Molecular epidemiology of peste des petits ruminants virus emergence in critically endangered Mongolian saiga antelope and other wild ungulates

“…PPRV is classified into four genetically distinct lineages, which can be discriminated based on phylogenetic analysis of short gene regions, often a few hundred nucleotides of the N gene ( Couacy-Hymann et al, 2002 ; Kumar et al, 2014 ). Lineage IV viruses have dominated both the host range and geographic expansion of PPRV seen in recent years and are now replacing other lineages in many African countries ( Libeau, Diallo, and Parida 2014 ; Tounkara et al, 2018 , 2021 ; Dundon, Diallo, and Cattoli 2020 ). Understanding this expansion is critical to mitigate challenges to the PPR GEP and to understand the threat of PPRV to biodiversity.…”

Peste Des Petits Ruminants in the Middle East: Epidemiological Situation and Status of Control and Eradication Activities after the First Phase of the PPR Global Eradication Program (2017–2021)

“…Four PPRV lineages (I–IV), all belonging to a single serotype, can be discriminated based on their genetic differences. Lineage I circulation has been historically limited to West Africa; long thought to be extinct, it has recently been detected again in Mali [ 12 ]. Lineage II is present in West and Central Africa, while lineage III has been reported only in East Africa and in the southern part of the Arabian Peninsula [ 13 ].…”