Migratory waterfowls from Europe as potential source of highly pathogenic avian influenza infection to Nigeria poultry

Highly pathogenic avian influenza H5N1 was detected for the first time in Nigeria and Africa in 2006. The source of the outbreak was not immediately clear, but scientific opinions favoured multiple introductions. The need to evaluate available epidemiological and virological data to demonstrate most probable source of introduction is important for focused control efforts. In this study, we described ten years (2006-2016) scientific observations available through ecology, epidemio-surveillance and molecular virology of avian influenza in Nigeria. Nigeria is geographically located in the tropical humid region with abundant wetlands presenting ideal ambience for birdlife. Ornithological evidence also showed that the country lies in the path of two major migratory flyways from Europe and Asia providing opportunities for co-mingling of different species and age of wild birds with resident birds. Genomic characterization including phylogenetic analysis revealed a high degree of homology among virus strains isolated in Nigeria and those detected in migratory birds from Europe suggesting common source epidemic. This study agreed with postulation that migratory wild birds from Europe may be responsible for the introduction of highly pathogenic avian influenza subtype H5N1 to Nigeria. Feral waterfowls around water bodies thereafter bridge transmission to domestic poultry holdings whereas local trade and movement of poultry and poultry products may further spread infection locally. In the light of this understanding, routine risk based sentinel surveillance for avian influenza in domestic waterfowls in ecological hotspots is recommended for early detection and response thereby saving economic losses and mitigating public health emergencies.Keywords: Avian influenza, Migratory waterfowls, Nigeria, Poultr

Serological evidence of influenza A/H9 in indigenous birds and level of awareness at live bird markets, Plateau State

Avian influenza is a zoonotic disease that can adversely affect humans and animals. Nigeria first reported an outbreak of avian influenza which was caused by subtype H5N1 in 2006, thereafter virological and serological surveys revealed the importance of local birds in live bird markets and the community at large in the epidemiology of avian influenza in the country. In the present study, 276 serum samples were collected for serological testing over five months from apparently healthy local birds in live bird markets within two Local Government Areas of Plateau State, to determine antibody prevalence to avian influenza A virus. The detection of influenza A antibody was carried out using an Enzyme-linked immunosorbent assay and further tested by haemagglutination inhibition to determine the specific serotype of the influenza A virus. The result showed a prevalence of 30.4% (n=84) of antibody to influenza A, 26% (n=72) of serotype H9, 1.4% (n=4) of serotype H7, and none was confirmed to be H5 serotype. Comparatively, Jos-North had a lower relative risk with a prevalence of 18.9% (n=18) to the disease as compared to Jos-South with a prevalence of 36.5% (n=66). This study showed the presence of low pathogenic avian influenza A virus in live bird markets within the study area with the dominance of antibodies to H9. To our knowledge, this is the first serological indication of serotype H9 in Plateau State and Nigeria. Evidence of influenza A/H9 in an ecological niche known for the circulation of subtypes H5Nx may complicate the epidemiology and control of avian influenza in the region and Nigeria at large. The level of awareness by the live bird market operators about avian influenza (AI) was relatively low as indicated by the questionnaire survey conducted. Live bird market operators and poultry farmers need to maintain a high level of biosecurity and limit mixing local birds with commercial poultry to prevent the transmission of the virus which may have adverse effects on poultry production, national and international trade, the economy and public health

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, Poultr

Outbreak of highly pathogenic avian influenza subtype H5N8 in two multi-age chicken farms in Jos, Plateau State, Nigeria

An outbreak of highly pathogenic avian influenza (HPAI) subtype H5N8 in two multi-age chicken flocks in Jos, Plateau State, Nigeria, is described. Diagnosis was made using tissue samples from the affected farms that were submitted to the Regional Lab for Animal Influenza and other Transboundary Animal Diseases, National Veterinary Research Institute, Vom. Pullets with broilers of 9 and 4 weeks of age respectively, from farm A (fA) and broilers, 4 weeks of age from farm B (fB) were submitted from flocks experiencing a drastic increase in mortality. The February 2019 outbreak resulted in10 – 60 % and 60 % mortality on fA and fB respectively. Clinical signs included anorexia, depression, hock sitting and sudden onset of increasing mortality. Gross lesions included edema of the head with cyanosis of comb and wattle; swollen abdomen due to ascites; generalized congestion of visceral organs with frank blood in the abdomen; congested mesenteric vessels with haemorrhages in the mucosa of small and large intestines; congested and frothy lungs with severe hemorrhagic tracheitis among others. In view of the clinical and gross pathology, HPAI was considered as the tentative diagnosis. Diagnosis of HPAI subtype H5N8 was confirmed by reverse transcriptase polymerase chain reaction and viral isolation in embryonated chicken eggs. The current outbreak has shown the presence of HPAI H5N8 in the country different from the H5N1 subtype that was introduced since 2006 in Nigeria. The co-circulation of these two subtypes if the current wave of infection is left unchecked will have adverse effects on poultry production, international trade and human health. Hence, the need for the re-evaluation and strengthening of the Government control policy to save the poultry industry from perennial economic loses.Keywords: Broilers, Highly pathogenic avian influenza (HPAI H5N8), Jos, Nigeria, Outbreaks, Pullet

Seroprevalence of avian leukosis virus in local chickens in five live bird markets, Kaduna metropolis, North-western Nigeria

Avian leukosis virus is recognized as an important viral pathogen in the poultry industry, resulting in salient severe economic losses due to reduced production, uneven flock growth rates, reduced growth, and immunosuppression which predispose affected birds to other infections. This study examined the seroprevalence of avian leukosis virus (ALV) in local chickens (LC) in 5 different live bird markets (LBMs) in Kaduna Metropolis. A total of 276 sera were tested for ALV p27 antigen using enzyme-linked immunosorbent assay (ELISA). An overall seroprevalence of 28.3% (78/276) was recorded in the study. At the market level, the seroprevalence of 35% (21/60), 30% (18/60), 32% (16/50), 28.6% (16/56), and 14% (7/50) were recorded for Sabon Tasha, Central market, Railway station, Kawo and Sokoto Road LBMs respectively. With regards to sex, female LC showed a significantly higher prevalence of 30.5% (46/105) compared to male chickens 26.9% (46/171) with no significant difference (P > 0.05) observed. This study established the presence of antigen to ALV in local chickens sold in LBMs. We recommend surveillance and further studies on the isolation, molecular characterization and pathogenicity of ALV in the study area

Footprints of swine influenza H1N1 and H3N2 in pigs from southern Kaduna, Nigeria

Influenza A virus presents a significant public health burden worldwide, with the 1918 Spanish flu pandemic being the most dramatic example. Swine influenza viruses can be transmitted to humans through occupational exposures and in live pig markets. Novel variants can emerge in pigs because they can be infected by human, avian and swine strains. This study was carried out to determine the seroprevalence and serotypes of swine influenza in pigs from a major slaughter slab in southern Kaduna. Using competitive ELISA and haemagglutination-inhibition (HI) assays, 305 swine sera were analysed. The result showed an overall seroprevalence of 28.20% (n=86), with H3N2 7.87% (n=24) emerging as the most dominant subtype in circulation. Concurrent antibody detection of H1N1 in 5.26% (n=16) was also detected in boar 2.62% (n=8) and sows 2.62% (n=8). This study revealed swine Influenza H1N1 and H3N2 serotypes are in circulation in pigs in Kaduna State, and that reassortment in the instance of co-infection of swine host is possible

Sero-prevalence and serotypes of infectious bronchitis virus in free-range chicken in Plateau state, Nigeria

Globally, infectious bronchitis (IB) is an important respiratory viral disease responsible for enormous economic losses to poultry farmers.  In Nigeria, limited reports on the prevalence and serotypes of the IB virus are available. Here, we investigated the prevalence and serotypes of infectious bronchitis virus (IBV) in chicken in Plateau State. A descriptive cross-sectional study was carried out involving 440 apparently healthy free-range local chickens sampled from eleven villages in four Local Government Areas (LGA) of Plateau State. Sera collected from the birds were screened for the presence of four IBV serotypes namely; Massachusetts (Mass), Arkansas (Ark), Connecticut (Con) and Delaware (De-072) using haemagglutinationinhibition (HI) test. In all, a prevalence of 82.95% (n = 365) was recorded. At LGAlevel, prevalence of 79.50%, 47.37%, 95.45% and 100% were recorded in Kanam, Mangu, Qua’an pan and Bassa LGAs, respectively. Based on serotype prevalence, Mass had 89.30% (n = 326); Ark 79.70% (n = 291); Con 88.20% (n = 322) while De-072 was 42.70% (n = 156). There were statistically significant associations between dominant serotype and the LGAs (p≤0.001). This study shows high prevalence of IBwith at least four strains of IBV present in free-range chicken flocks in Plateau State requiring attention for control measures. Keywords: Free-range chicken; Infectious bronchitis virus; Plateau state, Serosurvey, Serotyp

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

Multidisciplinary Knowledge sharing Approach in the Control of Zoonotic diseases in Nigeria: Motivations and Hindrances

This study explores factors that motivate and also factors that hinder knowledge sharing among public health professionals in managing zoonotic diseases in Plateau State, Nigeria. A qualitative method using a case study research design was used for the study. Data were collected through a semi-structured interview and focus group discussion. The analysis was done using qualitative content analysis. Findings revealed that; Forum to share knowledge, Adequate funding, Professional ethics, Policy, and Organizational support constitutes major motivating factors for multidisciplinary knowledge sharing; while Professional dichotomy, Negative traits, Monodisciplinary training, Lack of policy, Lack of funds, and Leadership Issues are major hindrances to multidisciplinary knowledge sharing in managing zoonotic infections in Plateau State, Nigeria.The approach to multidisciplinary knowledge sharing will be positive when factors that motivate public health professionals are adequately in place; these will result in a robust investigation of potential zoonotic diseases in Plateau State, Nigeria. However, factors that constitute hindrances are major setbacks in managing zoonotic diseases which must be addressed in order to harness the full potentials of the various public health professional working in Plateau State, Nigeria for the benefit of all. Keywords: Multidisciplinary knowledge sharing, Public Health professionals, Zoonotic Infection

Serological and molecular investigation of canine influenza virus in Plateau State, Nigeria

Canine influenza is a highly contagious respiratory infection of dogs caused by the Influenza A Virus (IAV), characterized by cough, sneeze, nasal secretions, and inappetence. Infections can be mild, severe or fatal. Aquatic birds constitute a natural reservoir for IAV, which is transmitted to terrestrial birds, including poultry. IAV has also emerged in other mammalian species, including humans, swine, horses, and dogs. IAV epidemics in dogs are a recent development. Commonly detected Canine Influenza Virus (CIV) strains are A/H3N2 and A/H3N8 from avian and equine influenza, respectively. Nigeria’s agro-ecology witnessed widespread circulation of avian influenza since 2006, and recent outbreaks of equine influenza in 2018/2019 raise the possibility of inter-species transmission to dogs. To investigate canine Influenza in Plateau State, we collected 113 nasal swabs and 270 sera samples from dogs in clinics, live dog markets, and during dog vaccination campaigns. After extracting nucleic acid with the Qiagen kit, RT-PCR analysed swabs for the Influenza A matrix gene. Sera samples were screened by Enzyme-Linked Immunosorbent Assay before subtyping a cross-section for H3 antibody by Hemagglutination Inhibition. No matrix gene was amplified from extracted nucleic acid from the nasal swabs. Though few sera were reactive to influenza A nucleoprotein, none was positive for influenza A/H3. The H3N8 strain of equine influenza virus first caused an epidemic in dogs in 1999 in the United States. Subsequently, avian-origin H3N2 CIV emerged in dogs in China and South Korea in 2005. Past CIV epidemics arose from a single cross-species transmission of H3N8 subtype from a mammalian intermediate host and the H3N2 subtype from an avian reservoir. Even though this limited investigation did not detect CIV in Plateau State, the potential remains because of the persistent circulation of avian, swine, and equine Influenza in Nigeria, which requires more extensive virological and serological surveillance