SEROLOGICAL AND MOLECULAR EPIDEMIOLOGY OF FOOT AND MOUTH DISEASE VIRUS IN RUMINANTS IN KADUNA AND PLATEAU STATES, NIGERIA

SEROLOGICAL AND MOLECULAR EPIDEMIOLOGY OF FOOT AND MOUTH DISEASE VIRUS IN RUMINANTS IN KADUNA AND PLATEAU STATES, NIGERIA

Abstract:

Foot and mouth disease virus (FMDV) has been known for centuries as one of the most fearful viral pathogens of cloven-hoofed domestic and wild animals, causing the foot and mouth disease (FMD), which exerts severe global economic impact on the livestock industry. FMD is endemic in Nigeria, with outbreaks which are mostly unreported occurring almost throughout the year in different parts of the country. The aim of this study was to investigate the epidemiology of FMD in Kaduna and Plateau States, Nigeria. Risk factors associated with FMD in the study areas were assessed via questionnaires administered to herdsmen. FMD prevalence was estimated using 3ABC enzyme-linked immunosorbent assay (3ABC ELISA) while antibodies against FMDV serotypes were detected by the solid phase competitive ELISA (SPCE) and the virus neutralization test (VNT). FMD viruses were isolated from ruptured epithelial tissue samples obtained from affected cattle in established cell layers and serotyped by antigen-capture ELISA. RNA was extracted from cell culture supernatant and the reverse transcription polymerase chain reaction (RT-PCR) was performed. The purified DNA amplicons were ligated into plasmid vector and pure clones were sequenced. The complete VP1 sequences were used for phylogenetic analysis. Farms with suspected FMD nearby, with contact with wildlife or with >100 animals, and animals of large ruminant species and in pastures other than nomadic grazing were significantly (P<0.05) associated with FMD. A 30.6% FMD sero-prevalence was estimated for Kaduna and Plateau States. Antibodies against five FMDV serotypes (O, A, SAT1, SAT2 and SAT3) were detected in Kaduna and Plateau States. Sixty FMDV isolates containing representative of serotypes O, A, SAT1 and SAT2 were recovered in Kaduna and Plateau States. The phylogenetic finding suggests these serotypes were genetically related to serotypes and topo types occurring in ix West, Central, East and North Africa. It also indicates the identification of a new genotype of SAT1 in Nigeria. The epidemiology of FMD in Kaduna and Plateau States is complex because of the occurrence of multiple serotypes/subtypes of the virus detected and the levels of variation observed has significant implications for disease control in Nigeria. Farmer education is needful and vaccination of domestic livestock with appropriate vaccine strains is recommended to mitigate virus spread

SEROLOGICAL AND MOLECULAR EPIDEMIOLOGY OF FOOT AND MOUTH DISEASE VIRUS IN RUMINANTS IN KADUNA AND PLATEAU STATES, NIGERIA