Assessment of Biosecurity Measures and Distribution of Daily Live Bird ‎Markets in Four North-Western States of Nigeria ‎

Maintenance of strict biosecurity measures is essential in preventing disease spread from Live Bird Markets (LBMs) which serve as a major intermingling area for poultry from different sources. This study assessed the Biosecurity measures and spatial distribution of daily Live Bird Markets of four North-western States in Nigeria. Closed ended questionnaires were administered in 35 daily LBMs in Kaduna, Kano, Katsina and Zamfara states and identification of disinfectants used in the LBMs were noted. Swab samples of birds’ cages in the LBMs were taken for E. coli isolation. The live bird managers and marketers were all male (100%) across all the four states. Only 6(17%) out of the 35 LBMs had high biosecurity level, 69% had a moderate biosecurity level and 5(14%) were graded as low. Of the 400 Live bird marketers administered questionnaires, only 71 (18%) employ good biosecurity practices and 305(76%) were graded as fair and remaining 24(6%) as poor. Majority of the LBMs were located within human settlements without any form of barrier. There were seven main types of disinfectants identified across the all LBMs. Esherichia coli was isolated from 1(17%) LBM among the 6(17%) LBMs that were identified to have and use disinfectant. From the remaining 29(83%) LBMs, E.coli was isolated from only 5(17%) despite lacking in use of disinfectant by these LBMs. Live bird marketers should be educated on the need to adhere to biosecurity measures and practices.

Biosecurity and Antimicrobial Use Practices in Live Bird Markets Within Abeokuta Metropolis, Southwest, Nigeria: A Preliminary Survey

The development of an antimicrobial stewardship plan (AMSP) for live bird sellers (LBS) requires an understanding of the current biosecurity status, antimicrobial use (AMU) and the practices involved in live bird selling (e.g., drivers, sellers, etc.) which is a direct source of poultry meat for human consumption. Seven Live Bird Markets (LBMs) within Abeokuta, Ogun State were surveyed using a semi-structured questionnaire. Data on LBMs characteristics, LBS demographics, biosecurity, and AMU practices, awareness on Antimicrobial Resistance (AMR), as well as preferred channels of information on antimicrobial stewardship were gathered. A total of 40 consenting LBS with 82.5% female and 17.5% male participants were included in the study. The participants’ mean age was 45.3 years (SD±11.9, range: 23-70 years). Laying hens, broilers, and cockerels were the main poultry types sold by LBS. Antimicrobials (AMs) were used for growth promotion (57.5%), therapeutic (40.0%), and prophylactic (2.5%) purposes. Tetracycline, metronidazole, and chloramphenicol were the most frequently used AMs. The majority of the participants (90.0%) have treated birds based on their empirical experience, with little or no inputs from veterinarians. Biosecurity and AMU practices were generally low (54.0% and 34.0%, respectively). The contact with veterinarians was associated with satisfactory biosecurity practices (p=0.049). No significant factors were found to be linked with AMU. This study has provided recent evidence-based data on practices in poultry management among LBS in Abeokuta, Ogun state. The findings would be useful for policy decisions and the development of AMSP on prudent AMU among LBS.

Genetic Characterization of Highly Pathogenic Avian Influenza A(H5N8) Virus in Pakistani Live Bird Markets Reveals Rapid Diversification of Clade 2.3.4.4b Viruses

The highly pathogenic (HPAI) avian influenza A(H5N1) viruses have undergone reassortment with multiple non-N1-subtype neuraminidase genes since 2008, leading to the emergence of H5Nx viruses. H5Nx viruses established themselves quickly in birds and disseminated from China to Africa, the Middle East, Europe and North America. Multiple genetic clades have successively evolved through frequent mutations and reassortment, posing a continuous threat to domestic poultry and causing substantial economic losses. Live bird markets are recognized as major sources of avian-to-human infection and for the emergence of zoonotic influenza. In Pakistan, the A(H5N1) virus was first reported in domestic birds in 2007; however, avian influenza surveillance is limited and there is a lack of knowledge on the evolution and transmission of the A(H5) virus in the country. We collected oropharyngeal swabs from domestic poultry and environmental samples from six different live bird markets during 2018–2019. We detected and sequenced HPAI A(H5N8) viruses from two chickens, one quail and one environmental sample in two markets. Temporal phylogenetics indicated that all novel HPAI A(H5N8) viruses belonged to clade 2.3.4.4b, with all eight genes of Pakistan A(H5N8) viruses most closely related to 2017 Saudi Arabia A(H5N8) viruses, which were likely introduced via cross-border transmission from neighboring regions approximately three months prior to virus detection into domestic poultry. Our data further revealed that clade 2.3.4.4b viruses underwent rapid lineage expansion in 2017 and acquired significant amino acid mutations, including mutations associated with increased haemagglutinin affinity to human α-2,6 receptors, prior to the first human A(H5N8) infection in Russian poultry workers in 2020. These results highlight the need for systematic avian influenza surveillance in live bird markets in Pakistan to monitor for potential A(H5Nx) variants that may arise from poultry populations.

Live Bird Markets in Nigeria: A Potential Reservoir for H9N2 Avian Influenza Viruses

Since 2006, multiple outbreaks of avian influenza (AI) have been reported in Nigeria involving different subtypes. Surveillance and molecular epidemiology have revealed the vital role of live bird markets (LBMs) in the dissemination of AI virus to commercial poultry farms. To better understand the ecology and epidemiology of AI in Nigeria, we performed whole-genome sequencing of nineteen H9N2 viruses recovered, from apparently healthy poultry species, during active surveillance conducted in nine LBMs across Nigeria in 2019. Analyses of the HA gene segment of these viruses showed that the H9N2 strains belong to the G1 lineage, which has zoonotic potential, and are clustered with contemporary H9N2 identified in Africa between 2016 and 2020. We observed two distinct clusters of H9N2 viruses in Nigeria, suggesting different introductions into the country. In view of the zoonotic potential of H9N2 and the co-circulation of multiple subtypes of AI virus in Nigeria, continuous monitoring of the LBMs across the country and molecular characterization of AIVs identified is advocated to mitigate economic losses and public health threats.

Avian influenza virus in water: global subtype diversity and spatial distribution patterns

The current COVID-19 pandemic highlights the need for zoonotic infectious disease surveillance. Avian influenza virus (AIV) poses a significant threat to animal and public health due to its pandemic potential. Virus-contaminated water has been suggested as an important AIV spread mechanism among multiple species. Nevertheless, few studies have characterized the global AIV subtype diversity and distribution in environmental water. Therefore, this study aims to provide an updated descriptive and phylogenetic analysis of AIVs isolated in water samples from high risk-sites for influenza outbreaks (i.e., live bird markets, poultry farms, and wild bird habitats) on a global scale. A total of 234 hemagglutinin (HA) gene sequences of 21 subtypes were reported from nine countries between 2003 – 2020. Fourteen AIV subtypes were solely reported from Asian countries. Most of the viral sequences were obtained in China and Bangladesh with 47.44% and 23.93%, respectively. Likewise, the greatest global AIV subtype diversity was observed in China with twelve subtypes. Live bird markets represented the main sampling site for AIV detection in water samples (64.10%), mostly from poultry cage water. Nevertheless, the highest subtype diversity was observed in water samples from wild bird habitats, especially from the Izumi plain and the Dongting Lake located in Japan and China, respectively. Water from drinking poultry troughs evidenced the greatest subtype diversity in live bird markets, meanwhile, environmental water used by ducks had the highest number of different subtypes in poultry farms. The maximum-likelihood phylogenetic tree showed that some HA sequences were closely related among different poultry/wild bird-related environments from different geographic origins. Therefore, the results suggest that even though the availability of HA gene sequences in public-access databases varies greatly among countries, environmental AIV surveillance represents a useful tool to elucidate potential viral diversity in wild and domestic bird populations.

Sero-Detection of Avian Influenza A/H7 in Nigerian Live-Bird Markets in Plateau State

Avian influenza has been reported in domestic birds in Nigeria since 2006 and subtype H5 of the Gs/Gg lineage has continued to be detected up till date. It has been suggested that waterfowls and local birds sold in live-bird markets may be natural reservoir and source of reinfection of different subtype of avian influenza in poultry farms. This study aims at serodetection of avian influenza virus in waterfowls and local birds at live-bird markets in Plateau State, Nigeria. A total of three hundred and nine (309) blood samples were collected over a period of three months and two hundred and ninety-two (292) sera were analysed by c-ELISA for influenza A nucleoprotein using standard protocols. Haemagglutination Inhibition (HI) specific for subtypes H5, H9, and H7 was also carried out using standard protocols on ELISA positive samples. The results showed seroprevalence of 5.14% (n=15) for influenza A. Serotype H7 was thereafter detected by HI in 5 of the 15 influenza A positive samples. The H7 positive sera also reacted with H7N3, H7N4, H7N1 and H7N7 virus strains with HI titre ranging between 1:32 to 1:512. This investigation for the first time showed serological evidence of influenza A subtype H7 in local birds and waterfowls sold at the live bird market in Nigeria. Further virological surveillance to isolate the virus is important in order to better understand influenza virus epidemiology in Nigeria and the potential risk that other subtypesof influenza poses to poultry production and public health. Keywords: Influenza A, subtype H7, serological detection, live bird market, Nigeria.

Occurrence and molecular detection of avian coronavirus in selected live bird markets, northwestern, Nigeria

Infectious bronchitis (IB) is one of the most common highly infectious viral respiratory diseases of poultry having wide geographical distribution. Yet, little is known about the infection in the northwestern states of Nigeria. In this study, a total of 263 pooled cloacal and tracheal swab samples were collected from apparently healthy avian species (duck, dove, geese, guinea fowl, local chicken, ostrich, parrot, pigeon, peacock, and turkey). The samples were from nine live bird markets in three states (Kaduna, Kano and Jigawa) of northwestern, Nigeria collected from September through November 2017. Total RNAs were extracted directly from the swab samples and screened for infectious bronchitis virus (IBV) using real-time reverse transcription-polymerase chain reaction. An overall prevalence of 38.0% (100/263)was recorded. IB was detected in 70 % (7/10) of the avian species with prevalence of 100 % in dove, local chicken 45.9 %, duck 42.3 %, geese 26.6 %, pigeon 23.5 %, turkey 20.0 % and guinea fowl 6.2 %. Conversely, no detection was made from ostrich, parrot, and peacock. Widespread distribution of IBV was observed and evidence of subclinical infection in seven out of ten (70 %) of the avian species sampled. These avian species harbouring IBV may act as reservoirs with an influence on the ecology and epidemiology of the disease. Continuous surveillance and characterization of the different serotypes in avian species are recommended to inform the adoption of suitable vaccination strategy and control measures for the disease in Nigeria. Keywords: Infectious bronchitis virus, Live bird markets (LBMs), Molecular detection, Nigeria, Poultry