Seroepidemiology and assessment of risk factors for the spread of avian influenza in birds in two Nigerian states

Abstract

Despite modified stamping out eradication policy adopted in Nigeria, there was resurgence in 2015 of highly pathogenic avian influenza (HPAI) H5N1 with greater infectivity. A survey of the risk of spread of HPAI in two HPAI‐infected and ‐uninfected Nigerian states were studied. A cross‐sectional study to detect avian influenza (AI) H5 antibodies was conducted using haemagglutination inhibition (HI) test and enzyme‐linked immunosorbent assay (ELISA). A total of 950 birds’ sera were tested for AI H5 antibodies. Questionnaires were also administered to evaluate risks of AI spread in two states of Nigeria in 2013. AI H5 seroprevalence of 3% and 5% were obtained in Bauchi and Gombe states, respectively. Free flying and captive wild birds had 15% and 11% seroprevalence, respectively. Ninety‐two per cent AI awareness and 90% preparedness to report outbreaks of poultry diseases were recorded. Veterinary personnel, radio and television contributed 87% to HPAI awareness. Of the 10 risk categories evaluated, Gombe state had 3 moderate and 1 high risk of AI virus spread. Bauchi state recorded 5 moderate and 1 high risk of AI virus spread. Chi‐square analysis showed associations of altitude, temperature, rainfall and presence of live bird markets (LBMs) (P < 0.05) to AI seroprevalence. Odds ratio at 95% CI (1.313–6.333) indicated LBMs presence to be three times more likely to influence AI occurrence. HPAI H5N1 resurged in many states and occurred for the first time in Gombe state in 2015. Veterinary personnel, radio and television may be reliable in changing farmers’ attitudes to adopt good biosecurity practices.

Potential risk factors of avian influenza virus infection in asymptomatic commercial chicken flocks in selected areas of Bangladesh during 2019

“…Poor biosecurity practice is a significant risk factor for the higher prevalence of AIV [ 42 ]. Waziri et al [ 43 ] demonstrated that chickens reared in poor biosecurity practices were three times more vulnerable to be spreaders of AIV compared to good biosecurity practicing farms, which is in accordance with the current findings. Osmani et al [ 16 ] conducted a case control study and reported an increased number of farm staffs (OR: 5.2), weekly visit of veterinarians (OR: 3.0), and roaming of village chickens around the farm (OR: 0.6) were the major biosecurity risk factors in commercial poultry farms in Bangladesh.…”

Disentangling the role of Africa in the global spread of H5 highly pathogenic avian influenza

“…In some African countries, illegal poaching of wild birds, which are kept in rural communities and then sold at markets, is not uncommon and may represent a possible bridge between wild and domestic birds 59 . The role of wild birds in the African continent is also supported by the virological and serological evidences of circulation of the H5 subtype in the wild population 51,60 , in particular during the most recent epidemic wave when HPAI H5N8 was widely detected in wild bird species in several countries such as Egypt 18 , Cameroon 12 , Uganda 13 and South Africa 15,17 . Moreover, in all epidemic waves the first outbreaks in Africa were reported between November and January ( Supplementary Fig.…”

Detection of antibodies to H5 and H9 subtypes of influenza viruses in wild birds in Zaria, Nigeria

“…Wild birds present a significant risk to poultry biosecurity because they can transmit disease causing agents including AIVs into poultry farms (Waziri et al, 2017). Here, apparently healthy wild birds at this wildlife and domestic birds interface were exposed to AIVs.…”