Complex Circulation of Foot-and-Mouth Disease Virus in Cattle in Nigeria

Abstract

Nigeria is a large densely populated country in West Africa. Most of its livestock is raised in a pastoralist production system with typical long distance migration in search of water and feed. As the demand for animal products largely exceeds the domestic production, large numbers of livestock are imported from neighboring countries without sanitary restrictions. In Nigeria, foot-and-mouth disease virus (FMDV) serotypes O, A, and Southern African Territories (SAT)2 are endemic for a long time. Clinical outbreaks of FMD due to serotype SAT1 are described again since 2015, after an absence of more than 30 years. Historically, outbreaks of FMD due to serotypes O, A, SAT1, and SAT2 were each time associated with trade of cattle entering Nigeria from neighboring countries. In the present study, tissue samples from 27 outbreaks of FMD were collected in Nigerian cattle from 2012 until 2017 in six different States and in the Federal Capital Territory. FMDV was isolated and serotyped and further characterized by VP1 sequencing and phylogenetic analysis to gain more knowledge on FMDV circulation in Nigeria. Half of the outbreaks were characterized as FMDV topotype O/EA-3, while outbreaks with other serotypes and topotypes were-in descending order-less prevalent: A/Africa/G-IV, SAT1/X, SAT2/VII, and O/WA. The high dynamics and omnipresence of FMD in Nigeria were illustrated in Plateau State where FMDV serotypes O, SAT1, and SAT2 were isolated during the course of the study, while at some point in the study, outbreaks due to FMDV serotype A were observed in three remote States. The genetic and phylogenetic analysis suggests a mixed origin of FMD outbreaks. Some outbreaks seem to be caused by sustained local transmission of FMDV strains present in Nigeria since a number of years, while other outbreaks seem to be related to recent incursions with new FMDV strains. The role of African buffaloes in the etiology of FMD in Nigeria is unclear, and sampling of wildlife is needed. The results of the present study suggest that systematic sample collection is essential to understand the complex concomitance of FMDV strains in Nigeria and essential to support the implementation of a vaccination-based control plan.

Outbreaks of Foot-and-Mouth Disease in Burundi, East Africa, in 2016, Caused by Different Serotypes

“…The obtained FMD viruses (FMDVs) were characterized and compared with previously characterized viruses from Burundi—if available—and neighboring countries. In one community of Cibitoke province, FMDVs of the serotypes A and SAT2 were isolated, confirming previous findings that in sub-Saharan Africa different FMD virus strains can circulate at the same place at the same time [ 9 , 10 , 11 ]. The isolated viruses were of the same topotypes as contemporary FMDVs from Uganda, Kenya, and Tanzania.…”

“…There are seven pools described [ 7 ] and Burundi, where the current study was conducted, belongs to pool 4 (Eastern Africa), with FMDV circulating serotypes O, A, SAT1, SAT2, and SAT3 [ 8 ], and is situated at the border with neighboring pool 5 (Western/Central Africa). FMD is endemic in most parts of Africa and the epidemiological situation is complex due to marked differences in the geographic distribution of serotypes, simultaneous presence of different serotypes and topotypes in the same region, high intratypic variation, and the presence of wildlife that can act as a reservoir [ 9 , 10 , 11 ]. In the ten-year period before the sampling year of this study (2016), multiple topotypes from FMDV serotypes O, A, SAT1, SAT2, and SAT3 were reported in Africa [ 12 ], with the last report of serotype C in 2004 [ 13 , 14 ].…”

Assessment of the control measures for category A diseases of Animal Health Law: Lumpy Skin Disease

“…Skin biopsies or nodules for virus isolation should preferably be collected within the first week of the occurrence of clinical signs (Davies, 1991). In contrast to viruses such as Foot and mouth disease virus (FMDV), where sequencing of a part of the genome like VP1 can be enough to determine the origin of the virus (Ularamu et al., 2020), this is not possible for LSDV. Sequencing of three to five different genes (Lamien et al., 2011; Agianniotaki et al., 2017) or Whole genome sequencing (WGS) of the LSDV can help to compare the virus with recently circulating viruses in other countries or regions (Mathijs et al., 2020) and with vaccine viruses (Mathijs et al., 2016).…”

Longitudinal study of foot-and-mouth disease virus in Northern Nigeria: implications for the roles of small ruminants and environmental contamination in endemic settings

“…Serotypes O, A, SAT 1 and SAT 2 have been isolated and characterised from cattle samples in Nigeria [7,[10][11][12]. These four serotypes belong to diverse topo-/genotypes and are phylogenetically related to strains circulating in West, Central and Northern Africa [8,11,13,14].…”