Orthopoxvirus Infections in Rodents, Nigeria, 2018-2019.

To investigate animal reservoirs of monkeypox virus in Nigeria, we sampled 240 rodents during 2018-2019. Molecular (real-time PCR) and serologic (IgM) evidence indicated orthopoxvirus infections, but presence of monkeypox virus was not confirmed. These results can be used to develop public health interventions to reduce human infection with orthopoxviruses.

Rational approach to vaccination against highly pathogenic avian influenza in Nigeria: a scientific perspective and global best practice.

Since 2006, highly pathogenic avian influenza (HPAI) subtypes H5Nx have adversely affected poultry production in Nigeria. Successive waves of infections in the last two decades have raised concerns about the ability to contain infections by biosecurity alone, and evidence of recurrent outbreaks suggests a need for adoption of additional control measures such as vaccination. Although vaccination can be used to control virus spread and reduce the morbidity and mortality caused by HPAI, no country using vaccination alone as a control measure against HPAI has been able to eliminate or prevent re-infection. To inform policy in Nigeria, we examined the intricacies of HPAI vaccination, government regulations, and scientific data regarding what kind of vaccines can be used based on subtype, whether inactivated or live attenuated should be used, when to deliver vaccine either proactively or reactively, where to apply vaccination either in disease control zones, regionally, or nationally, and how to vaccinate the targeted poultry population for optimum success. A resurgence of HPAI outbreaks in Nigeria since 2018, after the country was declared free of the epidemic following the first outbreak in 2006, has led to enhanced intervention. Controlled vaccination entails monitoring the application of vaccines, the capacity to differentiate vaccinated from infected (DIVA) flocks, and assessing seroconversion or other immune correlates of protection. Concurrent surveillance for circulating avian influenza virus (AIV) and analyzing AIV isolates obtained via surveillance efforts for genetic and/or antigenic mismatch with vaccine strains are also important. Countries with high investment in commercial poultry farms like Nigeria may identify and zone territories where vaccines can be applied. This may include ring vaccination to control HPAI in areas or production systems at risk of infection. Before adoption of vaccination as an additional control measure on commercial poultry farms, two outcomes must be considered. First, vaccination is an admission of endemicity. Secondly, vaccinated flocks may no longer be made accessible to international poultry markets in accordance with WOAH trade regulations. Vaccination must therefore be approached with utmost caution and be guided by science-based evidence throughout the implementation strategy after thorough risk assessment. Influenza vaccine research, development, and controlled application in addition to biosecurity may be a precautionary measure in the evolving HPAI scenario in Nigeria.

Sero-detection of antibodies to Avian metaavulavirus 2 in peri-domestic birds, Nigeria.

Avian metaavulavirus 2 (AMAV-2) previously known as the avian paramyxovirus-2 causes mild to severe respiratory disease, reduced hatchability and infertility of eggs, including increase in white-shelled eggs in chickens and Turkey breeders. When exacerbated by secondary pathogens and environmental stresses, infection is more severe leading to significant economic losses. This study was conducted to determine, if any, the presence of antibodies to Avian metaavulavirus 2 (AMAV-2) in peri-domestic birds in Bauchi State, Nigeria. In all, one hundred sera samples from pigeons (n = 10) and doves (n = 90 were collected in Bauchi, Nigeria. Based on hemagglutination-inhibition (HI) test, overall seroprevalence of 27.0% (27/100) was recorded. In pigeon, the seroprevalence was 80.0% while 21.1% was recorded for dove with HI antibody titers ranging from 3log2 to 8log2. There was statistical significance obtained between dove and pigeon sera tested (p < .05). Until now and to the best of our knowledge, there are no reports on AMAV-2 in poultry or wild birds in Nigeria. This study, thus, provides preliminary information on AMAV-2 seroprevalence in Nigerian peri-domestic birds. The need to conduct further studies in other avian species and wild birds in Nigeria is highlighted.

Genomic comparison of Newcastle disease viruses isolated in Nigeria between 2002 and 2015 reveals circulation of highly diverse genotypes and spillover into wild birds.

Newcastle disease virus (NDV) has a wide avian host range and a high degree of genetic variability, and virulent strains cause Newcastle disease (ND), a worldwide concern for poultry health. Although NDV has been studied in Nigeria, genetic information about the viruses involved in the endemicity of the disease and the transmission that likely occurs at the poultry-wildlife interface is still largely incomplete. Next-generation and Sanger sequencing was performed to provide complete (n = 73) and partial genomic sequence data (n = 38) for NDV isolates collected from domestic and wild birds in Nigeria during 2002-2015, including the first complete genome sequences of genotype IV and subgenotype VIh from the African continent. Phylogenetic analysis revealed that viruses of seven different genotypes circulated in that period, demonstrating high genetic diversity of NDV for a single country. In addition, a high degree of similarity between NDV isolates from domestic and wild birds was observed, suggesting that spillovers had occurred, including to three species that had not previously been shown to be susceptible to NDV infection. Furthermore, the first spillover of a mesogenic Komarov vaccine virus is documented, suggesting a previous spillover and evolution of this virus. The similarities between viruses from poultry and multiple bird species and the lack of evidence for host adaptation in codon usage suggest that transmission of NDV between poultry and non-poultry birds occurred recently. This is especially significant when considering that some viruses were isolated from species of conservation concern. The high diversity of NDV observed in both domestic and wild birds in Nigeria emphasizes the need for active surveillance and epidemiology of NDV in all bird species.

Investigation of suspected Newcastle disease (ND) outbreaks in Egypt uncovers a high virus velogenic ND virus burden in small-scale holdings and the presence of multiple pathogens.

Highly contagious Newcastle disease (ND) is associated with devastating outbreaks with highly variable clinical signs among gallinaceous birds. In this study we aimed to verify clinical ND suspicions in poultry holdings in Egypt suffering from respiratory distress and elevated mortality, comparing two groups of ND-vaccinated poultry holdings in three governorates. Besides testing for Newcastle disease virus (NDV), samples were screened for infectious bronchitis virus (IBV) and avian influenza virus (AIV) by RT-qPCR as well as by non-directed cell-culture approach on LMH-cells. Virulent NDV was confirmed only in group A (n = 16) comprising small-scale holdings. Phylogenetic analysis of the fusion protein gene of 11 NDV-positive samples obtained from this group assigned all viruses to genotype 2.VIIb and point to four different virus populations that were circulating at the same time in one governorate, indicating independent epidemiological events. In group B, comprising large commercial broiler farms (n = 10), virulent NDV was not present, although in six farms NDV vaccine-type virus (genotype 2.II) was detected. Besides, in both groups, co-infections by IBV (n = 10), AIV H9 (n = 3) and/or avian reovirus (ARV) (n = 5) and avian astrovirus (AastVs) (n = 1) could be identified. Taken together, the study confirmed clinical ND suspicion in small scale holdings, pointing to inefficient vaccination practices in this group A. However, it also highlighted that, even in an endemic situation like ND in Egypt, in cases of suspected ND vaccine failure, clinical ND suspicion has to be verified by pathotype-specific diagnostic tests. RESEARCH HIGHLIGHTS Velogenic NDV circulates in small-scale poultry holdings in Egypt. Viral transmission occurred among neighbouring farms and over long distances. Co-infections with multiple pathogens were identified. Pathotype specific diagnostic tests are essential to verify ND suspicions.

The emerging influenza virus threat: status and new prospects for its therapy and control.

Influenza A viruses (IAVs) are zoonotic pathogens that cause yearly outbreaks with high rates of morbidity and fatality. The virus continuously acquires point mutations while circulating in several hosts, ranging from aquatic birds to mammals, including humans. The wide range of hosts provides influenza A viruses greater chances of genetic re-assortment, leading to the emergence of zoonotic strains and occasional pandemics that have a severe impact on human life. Four major influenza pandemics have been reported to date, and health authorities worldwide have shown tremendous progress in efforts to control epidemics and pandemics. Here, we primarily discuss the pathogenesis of influenza virus type A, its epidemiology, pandemic potential, current status of antiviral drugs and vaccines, and ways to effectively manage the disease during a crisis.

Highly pathogenic avian influenza (H5N1) in Nigeria in 2015: evidence of widespread circulation of WA2 clade 2.3.2.1c.

Genetic analysis of the complete haemagglutinin (HA) gene of fourteen Nigerian avian influenza isolates showed multiple basic amino acids at the cleavage site (321PQRERRRK del R*GLF333), characteristic of highly pathogenic avian influenza (HPAI). Substitution of Gln to Lys at position 322 (H5-specific numbering) was identified in one isolate. In some isolates, amino acid substitutions were observed across the HA gene, however the receptor binding, antigenic and glycosylation sites were conserved in all. Phylogenetic analysis revealed two clusters of the HPAI H5N1 clade 2.3.2.1c. Cluster I has close genetic relatedness (97.8-99.8%) with viruses circulating in some West Africa countries. Cluster II shared close identity (98.9-100.0%) with isolates from Europe, Côte d'Ivoire and Niger and viruses from this cluster were detected in five of the eleven states investigated in Nigeria. In view of the continuous HPAI outbreaks being recorded in Nigerian poultry and the zoonotic potential of the virus, extensive and continued characterization of HPAI isolates is advocated.

Genetically Different Highly Pathogenic Avian Influenza A(H5N1) Viruses in West Africa, 2015.

To trace the evolution of highly pathogenic influenza A(H5N1) virus in West Africa, we sequenced genomes of 43 viruses collected during 2015 from poultry and wild birds in 5 countries. We found 2 co-circulating genetic groups within clade 2.3.2.1c. Mutations that may increase adaptation to mammals raise concern over possible risk for humans.

The close genetic relationship of lineage D Betacoronavirus from Nigerian and Kenyan straw-colored fruit bats (Eidolon helvum) is consistent with the existence of a single epidemiological unit across sub-Saharan Africa.

Straw-colored fruit bats (Eidolon helvum), which have been identified as natural hosts for several zoonotic pathogens, such as lyssaviruses, henipaviruses, and ebolavirus, are associated with human settlements in Nigeria where they are commonly consumed as a delicacy. However, information on the viruses harbored by these bats is scarce. In this study, coronavirus sequences were detected using a nested RT-PCR targeting 440 bp of the RNA-dependent RNA polymerase (RdRp) in six of 79 fecal samples collected from an urban colony of E. helvum in Ibadan, Nigeria. Phylogenetic analysis revealed that all six sequences were monophyletic and clustered in lineage D of Betacoronavirus. The extension of two fragments allowed us to classify our sequences within the RdRp Group Unit defined for Kenyan Betacoronavirus from the same host species. These findings are consistent with the previous suggestion on the existence of a single epidemiological unit of E. helvum across sub-Saharan Africa. This theory, which is supported by the genetic structure of continental E. helvum, could facilitate viral mixing between different colonies across the continent.

Serological evidence of equine influenza virus in horse stables in Kaduna, Nigeria.

Equine influenza virus (EIV) is a major cause of acute respiratory diseases in horses in most parts of the world that results in severe economic losses. Information on the epidemiology of EIV in tropical Africa is scanty. An enzyme-linked immunosorbent assay (ELISA) was used to detect the presence of influenza A virus nucleoprotein (NP) in 284 horse sera in Kaduna State, Northern Nigeria. The ELISA-positive sera were further examined for hemagglutination inhibition (HI) antibodies to two strains each of H3N8 and H7N3 subtypes of influenza A virus. The results showed that antibodies against influenza A virus nucleoprotein were detected in 60.9% (173 of 284) of horses examined by NP-ELISA. Equine H3 and H7 subtypes were detected in 60% (21 of 35) and 20% (7 of 35) of horse sera respectively across the stables. Adequate quarantine of all imported horses, a national equine influenza surveillance plan and an appropriate EIV control program in Nigeria are recommended to safeguard the large horse population.

Detection of clade 2.3.4.4 highly pathogenic avian influenza H5 viruses in healthy wild birds in the Hadeji-Nguru wetland, Nigeria 2022.

Background: The introduction of multiple avian influenza virus (AIV) subtypes into Nigeria has resulted in several poultry outbreaks purportedly linked to trade and wild birds. The role of wild birds in perpetuating AIV in Nigeria was, therefore, elucidated. Methods: A cross-sectional study was conducted among wild aquatic bird species at the Hadejia-Nguru wetlands in Northeastern Nigeria between March and April 2022. A total of 452 swabs (226 cloacae and 226 oropharyngeal) were collected using a mist net to capture the birds. These samples were tested by RT-qPCR, followed by sequencing. Results: Highly pathogenic AIV of the H5N1 subtype was identified in clinically healthy wild bird species, namely, African jacana, ruff, spur-winged goose, squared-tailed nightjar, white-faced whistling ducks, and white stork. A prevalence of 11.1% (25/226) was recorded. Phylogenetic analysis of the complete HA gene segment indicated the presence of clade 2.3.4.4b. However, these H5N1 viruses characterized from these wild birds cluster separately from the H5N1 viruses characterized in Nigerian poultry since early 2021. Specifically, the viruses form two distinct genetic groups both linked with the Eurasian H5N1 gene pool but likely resulting from two distinct introductions of the virus in the region. Whole-genome characterization of the viruses reveals the presence of mammalian adaptive marker E627K in two Afro-tropical resident aquatic ducks. This has zoonotic potential. Conclusion: Our findings highlight the key role of surveillance in wild birds to monitor the diversity of viruses in this area, provide the foundations of epidemiological understanding, and facilitate risk assessment.

Prevalence of multidrug-resistant Escherichia coli isolates and virulence gene expression in poultry farms in Jos, Nigeria.

Introduction: Antimicrobial resistance is increasingly becoming a global health concern. This study aimed to investigate and report MDR Escherichia coli (E. coli) prevalence, resistance, and virulence genes from poultry in Jos, Plateau State, Nigeria. Methods: The samples were analyzed using microbiological standard methods and polymerase chain reactions (PCRs). Results: A total of 179 cloacal swabs were collected from bothlocal and exotic poultry breeds, of which 99.4% (178/179) tested positive for E. coli. Among these culturally identified samples, 99.4% (177/178) were furtherconfirmed Escherichia coli with a molecular weight of 401 bp. Multidrugresistance of 45% (80/178) was observed from the confirmed isolates. PCR assays were conducted to detect genes associated with resistance to antibiotics, specifically, tetracycline (tetA gene), sulfonamide (sul1 gene), ampicillin (ampC gene), and quinolone (gyrA gene). Antimicrobial susceptibility test (AST) results revealed substantial antibiotic resistance, with 81.9% (145/177) of the isolates being resistant to tetracycline, 80.2% (142/177) to quinolone, 69.5% (123/177) to sulfonamide, and 66.1% (117/177) to ampicillin. Further analysis on 18 isolates that showed resistance to up to four different antibiotics was carried out using multiplex PCR to detect eae, hlyA, rfbE, fliC, and fstx virulence genes. The study found that 44.4% (15/18) of the isolates were positive for the eae gene, 27.7% (5/18) for stx, 22.2% (4/18) for rfbe gene, and 5.5% (1) for hlya gene, and none tested positive for fliC gene. Conclusion: These results showed high antibiotic resistance, virulent genes, and significant levels of MDR in E. coli from poultry. This study highlights the urgent need for antimicrobial stewardship practices within the poultry industry due to their profound implications for food safety and public health. This issue is particularly critical in Nigeria, where poultry farming constitutes a significant portion of smallholder farming practices.

SARS-CoV and SARS-CoV -2 cross-reactive antibodies in domestic animals and wildlife in Nigeria suggest circulation of sarbecoviruses.

Anthropogenic exposure of domestic animals, as well as wildlife, can result in zoonotic transmission events with known and unknown pathogens including sarbecoviruses. During the COVID-19 pandemic, SARS-CoV-2 infections in animals, most likely resulting from spill-over from humans, have been documented worldwide. However, only limited information is available for Africa. The anthropozoonotic transmission from humans to animals, followed by further inter- and intraspecies propagation may contribute to viral evolution, and thereby subsequently alter the epidemiological patterns of transmission. To shed light on the possible role of domestic animals and wildlife in the ecology and epidemiology of sarbecoviruses in Nigeria, and to analyze the possible circulation of other, undiscovered, but potentially zoonotic sarbecoviruses in animals, we tested 504 serum samples from dogs, rabbits, bats, and pangolins collected between December 2020 and April 2022. The samples were analyzed using an indirect multi-species enzyme-linked immunosorbent assay (ELISA) based on the receptor binding domain (RBD) of SARS-CoV and SARS-CoV -2, respectively. ELISA reactive sera were further analyzed by highly specific virus neutralization test and indirect immunofluorescence assay for confirmation of the presence of antibodies. In this study, we found SARS-CoV reactive antibodies in 16 (11.5%) dogs, 7 (2.97%) rabbits, 2 (7.7%) pangolins and SARS-CoV-2 reactive antibodies in 20 (13.4%) dogs, 6 (2.5%) rabbits and 2 (7.7%) pangolins, respectively. Interestingly, 2 (2.3%) bat samples were positive only for SARS-CoV RBD reactive antibodies. These serological findings of SARS-CoV and/or SARS-CoV-2 infections in both domestic animals and wildlife indicates exposure to sarbecoviruses and requires further One Health-oriented research on the potential reservoir role that different species might play in the ecology and epidemiology of coronaviruses at the human-animal interface.

Phylogenetic analysis of Newcastle disease viruses isolated from asymptomatic guinea fowls (Numida meleagris) and Muscovy ducks (Cariana moscata) in Nigeria.

Four Newcastle disease virus isolates were recovered from asymptomatic guinea fowl (Numida meleagris galeata) and Muscovy ducks (Cariana moscata). For the purpose of molecular identification and phylogeny, phylogenetic characterization was performed to identify the pathotypes. All four viruses had a cleavage motif (112)RRQKRF(117) which is characteristic of virulent strains. The isolates grouped with viruses previously reported as sub-lineage 5 g from chickens in Nigeria. This study report for the first time the identification of the virulent sub-lineage 5 g Newcastle disease virus from apparently healthy guinea fowl and domestic ducks in Nigeria, and since infections were sub-clinical, it suggest that these species could play a role in the spread and transmission of virulent Newcastle disease virus that can infect other poultry. The isolation and identification of virulent Newcastle disease virus in these unusual hosts and the high sequence similarity (99.3-100 %) between viruses in this study with strains reported for Niger and Cameroun gives insights into the ecology of virulent Newcastle disease viruses and suggests some cross-border movement and trade in live poultry.

Antiviral options and therapeutics against influenza: history, latest developments and future prospects.

Drugs and chemotherapeutics have helped to manage devastating impacts of infectious diseases since the concept of 'magic bullet'. The World Health Organization estimates about 650,000 deaths due to respiratory diseases linked to seasonal influenza each year. Pandemic influenza, on the other hand, is the most feared health disaster and probably would have greater and immediate impact on humanity than climate change. While countermeasures, biosecurity and vaccination remain the most effective preventive strategies against this highly infectious and communicable disease, antivirals are nonetheless essential to mitigate clinical manifestations following infection and to reduce devastating complications and mortality. Continuous emergence of the novel strains of rapidly evolving influenza viruses, some of which are intractable, require new approaches towards influenza chemotherapeutics including optimization of existing anti-infectives and search for novel therapies. Effective management of influenza infections depend on the safety and efficacy of selected anti-infective in-vitro studies and their clinical applications. The outcomes of therapies are also dependent on understanding diversity in patient groups, co-morbidities, co-infections and combination therapies. In this extensive review, we have discussed the challenges of influenza epidemics and pandemics and discoursed the options for anti-viral chemotherapies for effective management of influenza virus infections.

Genomic Analysis of Infectious Bursal Disease Virus in Nigeria: Identification of Unique Mutations of Yet Unknown Biological Functions in Both Segments A and B.

Infectious bursal disease (IBD) is a viral poultry disease known worldwide for impacting the economy and food security. The disease is endemic in Nigeria, with reported outbreaks in vaccinated poultry flocks. To gain insight into the dynamics of infectious bursal disease virus (IBDV) evolution in Nigeria, near-complete genomes of four IBDVs were evaluated. Amino acid sequences in the hypervariable region of the VP2 revealed conserved markers (222A, 242I, 256I, 294I and 299S) associated with very virulent (vv) IBDV, including the serine-rich heptapeptide motif (SWSASGS). Based on the newly proposed classification for segments A and B, the IBDVs clustered in the A3B5 group (where A3 are IBDVs with vvIBDV-like segment A, and where B5 are from non-vvIBDV-like segment B) form a monophyletic subcluster. Unique amino acid mutations with yet-to-be-determined biological functions have been observed in both segments. Amino acid sequences of the Nigerian IBDVs showed that they are reassortant viruses. Circulation of reassortant IBDVs may be responsible for the vaccination failures observed in the Nigerian poultry population. Close monitoring of changes in the IBDV genome is recommended to nip deleterious changes in the bud through the identification and introduction of the most appropriate vaccine candidates and advocacy/extension programs for properly implementing disease control.

Serological evidence of Newcastle disease virus antibodies in wild birds in Zaria, Kaduna State, Nigeria.

Wild birds have been reported to be reservoirs of viral diseases of poultry, and play an epidemiological role in their maintenance and spread. A serological survey was undertaken to determine the evidence of Newcastle disease virus (NDV) antibodies in wild birds in Zaria Kaduna State, Nigeria. A total of 150 apparently healthy wild birds comprising 30 each laughing dove, speckled pigeons, cattle egrets, village weavers and African silver bills were sampled. Sera collected were analysed for the presence of antibodies against NDV and avian paramyxovirus­2 (APMV­2) using the haemagglutination inhibition test. The results showed an overall seroprevalence of 4% (95% CI: 2.05­10.1) to NDV. African silver bill showed a seroprevalence of 10.0% (95% CI: 2.61­24.9) NDV antibodies while seroprevalence of 3.3% (95% CI: 0.16­15.4) was recorded for cattle egrets, village weavers and laughing doves respectively. No statistically significant difference existed for NDV seroprevalence (P>0.05) among the different species of wild birds. All the 150 sera tested negative for APMV­2 antibodies. The result of this study confirmed the exposure of wild birds to NDV in the study area. Continuous surveillance with isolation and characterization of NDV in the wild birds is therefore recommended for strategic planning for control.

Poxvirus Infections in Dairy Farms and Transhumance Cattle Herds in Nigeria.

Lumpy Skin disease (LSD) is an economically important disease in cattle caused by the LSD virus (LSDV) of the genus Capripoxvirus, while pseudocowpox (PCP) is a widely distributed zoonotic cattle disease caused by the PCP virus (PCPV) of the genus Parapoxvirus. Though both viral pox infections are reportedly present in Nigeria, similarities in their clinical presentation and limited access to laboratories often lead to misdiagnosis in the field. This study investigated suspected LSD outbreaks in organized and transhumance cattle herds in Nigeria in 2020. A total of 42 scab/skin biopsy samples were collected from 16 outbreaks of suspected LSD in five northern States of Nigeria. The samples were analyzed using a high-resolution multiplex melting (HRM) assay to differentiate poxviruses belonging to Orthopoxvirus, Capripoxvirus, and Parapoxvirus genera. LSDV was characterized using four gene segments, namely the RNA polymerase 30 kDa subunit (RPO30), G-protein-coupled receptor (GPCR), the extracellular enveloped virus (EEV) glycoprotein and CaPV homolog of the variola virus B22R. Likewise, the partial B2L gene of PCPV was also analyzed. Nineteen samples (45.2%) were positive according to the HRM assay for LSDV, and five (11.9%) were co-infected with LSDV and PCPV. The multiple sequence alignments of the GPCR, EEV, and B22R showed 100% similarity among the Nigerian LSDV samples, unlike the RPO30 phylogeny, which showed two clusters. Some of the Nigerian LSDVs clustered within LSDV SG II were with commonly circulating LSDV field isolates in Africa, the Middle East, and Europe, while the remaining Nigerian LSDVs produced a unique sub-group. The B2L sequences of Nigerian PCPVs were 100% identical and clustered within the PCPV group containing cattle/Reindeer isolates, close to PCPVs from Zambia and Botswana. The results show the diversity of Nigerian LSDV strains. This paper also reports the first documented co-infection of LSDV and PCPV in Nigeria.

The Evolution of Highly Pathogenic Avian Influenza A (H5) in Poultry in Nigeria, 2021-2022.

In 2021, amidst the COVID-19 pandemic and global food insecurity, the Nigerian poultry sector was exposed to the highly pathogenic avian influenza (HPAI) virus and its economic challenges. Between 2021 and 2022, HPAI caused 467 outbreaks reported in 31 of the 37 administrative regions in Nigeria. In this study, we characterized the genomes of 97 influenza A viruses of the subtypes H5N1, H5N2, and H5N8, which were identified in different agro-ecological zones and farms during the 2021-2022 epidemic. The phylogenetic analysis of the HA genes showed a widespread distribution of the H5Nx clade 2.3.4.4b and similarity with the HPAI H5Nx viruses that have been detected in Europe since late 2020. The topology of the phylogenetic trees indicated the occurrence of several independent introductions of the virus into the country, followed by a regional evolution of the virus that was most probably linked to its persistent circulation in West African territories. Additional evidence of the evolutionary potential of the HPAI viruses circulating in this region is the identification in this study of a putative H5N1/H9N2 reassortant virus in a mixed-species commercial poultry farm. Our data confirm Nigeria as a crucial hotspot for HPAI virus introduction from the Eurasian territories and reveal a dynamic pattern of avian influenza virus evolution within the Nigerian poultry population.

Molecular Detection of Peste des Petits Ruminants Virus (PPRV) in Goats and in Sheep in Ibadan, Oyo State, Nigeria.

Peste des petits ruminants (PPR) is a vaccine-preventable transboundary animal disease of goats and sheep majorly, and is regarded as a major constraint to small ruminant production especially in developing countries like Nigeria. Despite different strategies that have been employed to control PPR in Nigeria, cases of the disease are still reported in PPR-vaccinated and unvaccinated small ruminant farms. In this study, molecular detection of field PPR virus (PPRV) strains was carried out to determine the presence of PPRV. A total of 135 samples (45 oculo-nasal swabs and 90 tissue samples) were purposively collected between August and October 2020 from goats and sheep at the Akinyele live small ruminant market and at Akinyele and Amosun abattoirs in Ibadan, Oyo State, Nigeria. Using reverse transcriptasepolymerase chain reaction with primers targeting the partial N-gene of PPRV, 10 out of the 135 (7.4%) field samples yielded positive results. The results of this study reveal that PPRV currently circulates in Ibadan. These findings underscore the need for continuous PPR surveillance, more extensive characterization of circulating PPRV strains and the importance of consistent use of quality vaccines in the country to achieve more effective preventive and control strategies against the disease.