Ijomanta, J.1,+, Asala, O.1, Bitrus, M.1, Musa, A.2, Shittu, I.1, Joannis, T.1, Nwosuh, C.1 and 1Meseko, C.*

1Regional Centre for Animal Influenza, National Veterinary Research Institute, Vom Nigeria; 2Veterinary Department, Plateau State Ministry of Agriculture, Jos Nigeria

+presenting author

*Corresponding author: cameseko@yahoo.com

Influenza virus A belongs to the family Orthomyxoviridae and is divided into subtypes H1-18. The virus affects a wide range of avian and mammalian hosts, subtypes H1; H3; H5; H7 and H9 have been reported to cause fatal infections that can adversely affect socio-economics and public health. In April 2009, WHO declared influenza pandemic when H1N1pdm09 spread to 214 countries and an estimated 151,700 –575 400 deaths were recorded. The virus was subsequently transmitted to pigs and had remained enzootic being detected in many countries including Nigeria.

In this study, a total of 143 tracheal swabs were collected during a targeted active surveillance of apparently healthy pigs in Jos abattoir, Plateau state from December 2017 through February 2018. The samples were analyzed for Influenza A by conventional One-step RT-PCR protocol targeting the matrix. To subtype the Influenza A viruses, multiplex RT-qPCR assays targeting the Hemagglutinin (H1pdm, H1avian, H1human and H3) and neuraminidase (N1, N2, N1pdm) were used. In all, 51 (35%) samples were positive for Influenza A while four of the ten selected samples for subtyping were identified as H1N1pdm09.

In a previous study carried out at the human-animal interface, circulation of H1N1pdm09 was reported in southwest Nigeria. Also, follow up studies revealed seroprevalence ranging from 20-60% in pigs. Here, we report a more recent and continuous circulation of the virus in pigs in North central Nigeria since it was first declared a pandemic in 2009. The virus in human is now seasonal and can easily be managed with vaccination. Currently, there is no vaccination programme for swine influenza in Nigeria therefore maintaining H1N1pdm09 in pigs poses great public health risk. Possible mutations and reassortments may result in emergence of novel virus with pandemic potential.

Keywords: surveillance; Influenza A virus; Nigeria; Pandemics; Pigs

Oladipo E.K.*1,2, Adeniji J.A.3, Oloke J.K2

1Department of Microbiology, Laboratory of Molecular Biology and Bioinformatics, Adeleke University, Ede, Osun State, Nigeria; 2Department of Pure and Applied Biology (Microbiology / Virology Unit), Ladoke Akintola University of Technology, Ogbomoso, Oyo State, Nigeria; 3Department of Virology, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria

Introduction: Pigs are susceptible to infections with both avian and mammalian Influenza A viruses. Pigs play an important role in the ecology of influenza virus. The changing epidemiology of influenza has a significant implications for the circulation of viruses in pigs. Little is known about the circulating strains in this area. To understand the current the current situation regarding influenza viruses circulating among pigs in Ogbomoso, a surveillance study was conducted.

Methods: Viral isolation from nasal swabs collected from one hundred pigs was performed using egg inoculation, MDCK and haemagglutination assay. Reverse transcriptase polymerase chain reaction (RT-PCR) was carried out by amplifying the matrix gene for identification. The sequence was determined by Sanger dideoxy sequencing. The homology analysis was implemented by Influenza Research database (IRD) and phylogenetic analysis was performed by Maximum – Likelihood methods using MEGA 7.10 software package.

Results: Multiple sequence alignment showed that the matrix (M) genes of A/H5N1/Ogbomoso/2014 influenza virus showed highest nucleotide identity with A/Pigeon/Sichuan/NCXN29/2014(H5N1) and A/Duck/Sichuan/NCXN11/2014 (H5N1) {98% and 97% respectively}. The phylogenetic analysis of the matrix gene of A/H5N1/Ogbomoso/2014 indicated that this virus is closely related to H5N1 strains circulating in southwest China.

Conclusion: This is the first report of genetic characterization of influenza A virus H5N1 of swine origin isolate from Ogbomoso. The presented results can further promote Influenza A virus surveillance and epidemiology insight in this community. The potential role of pigs in interspecies transmission remains important.

Keywords: Pigs, H5N1, Ogbomoso, Influenza A, Genetic Characterization.