Molecular and serological detection of Newcastle disease virus in live-bird markets, Jos, Plateau State Nigeria.

Newcastle disease (ND) is a highly infectious viral disease of birds caused by the Newcastle disease virus (NDV) and it has been reported in domestic birds in Nigeria. Waterfowls and village poultry in live bird markets (LBM) acts as reservoirs, potentially reintroducing the virus to commercial poultry. This study aims at molecular and serological detection of NDV at live bird markets in Plateau State, Nigeria. A cross sectional analysis involved 309 pooled cloacal and tracheal swabs over three months were analyzed by reverse transcriptase polymerase chain reaction (RT-PCR), RT-qPCR, virus isolation and haemagglutination and haemagglutination-inhibition test (HA &HI). Virus isolation was attempted in 9 to 11 days old specific antibody negative (SAN) embryonated chicken eggs and fifteen samples showed haemagglutination. Subsequent tests confimed nine of these as NDV positive through haemagglutination and haemagglutination inhibition (HI) tests. ConventionalRT-PCR and RT-qPCR further validated five of the nine NDV positive isolates. The phylogenetic analysis of partial F gene nucleotide sequences revealed that all three isolates belonged to class II genotype XIV.2_XIVb. This finding underscores the persistent threat of NDV to local poultry, necessitating comprehensive virological surveillance to understand, isolate and characterize the virus in Nigeria. Therefore, monitoring for emerging lineages and sub-lineages in Nigeria birds is crucial for safeguarding commercial poultry production.