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

Incursion of Foot-and-Mouth Disease (FMD) Serotype O East Africa Topotype -3 (O/EA-3) in Nigeria

Foot-and-mouth disease (FMD) is an endemic transboundary animal disease that affects livestock health across most of sub-Saharan Africa. Since the first official report of FMD in Nigeria in 1924, serotypes O, A, SAT 1 and SAT 2 have been documented within the  country. Molecular epidemiology has been used to trace the origin of FMD outbreaks in the case of animal movement, inter-species transmissions and trans-continental introductions. Phylogenetic analyses of VP1 nucleotide sequences of the twelve isolates (n=12) provide evidence for the presence of type O/EAST AFRICA 3 (EA-3) in Nigeria. The epidemiological situation of FMD in Nigeria and other West African countries is further complicated by the emergence of the O/EA-3 lineage that is causing new outbreaks in the region in addition to the West Africa (WA) topotype that has been known to be in circulation in Nigeria and other parts of West African and  Central African regions. These recent development in west and central Africa, indicates the dynamic and complex nature of FMD epidemiology in the region and this is not un-connected to the nomadism in the region. In addition the un-restricted animal movement across the porous border in the region in search of pasture and water for their animal has contributed to the spread of diseases across  the region. From the results the phylogenetic analysis of the O/EA-3 has close identity and was closely related to O/EA-3 from the 2009 outbreak in Sudan. Therefore, based on these findings a sustained surveillance is required to yet understand the epidemiology of FMD  in West and Central Africa that will inform the type of vaccine and target areas in other to control the disease. The need to restrict animal movement across the border should be put in place and where necessary all animals that must move from one point to another  must have proper evidence of vaccine certification before it should be allow access into the area. Finally for effective FMD control, regional vaccination and surveillance should be advocated and it should be backed by law. The need to have FMD vaccination at national as well as regional FMD control policy is strongly advocate for effective FMD control in Nigeria and across the regions. Key words: Topotype, West African; FMD and Nigeri

The Control of Neglected Zoonotic Diseases in Nigeria through Animal Intervention

Zoonoses are a major cause of morbidity and mortality across the world and particularly in Nigeria; however, they are often neglected by primary healthcare managers and policy makers. The neglected zoonotic diseases endemic in Nigeria include Anthrax, brucellosis, Bovine Tuberculosis, Rabies, Lassa Fever, Animal Trypanosomosis and Echinococcosis. With a population of over 140million people, urbanisation, economic development; and the concomitant intensification of animal husbandry coupled with the development of peri-urban livestock production systems, the risk posed by these neglected zoonoses are enormous. Their control in Nigeria is nearly non-existent and their impact on human health is largely unknown. The possible risk factors associated with their occurrences have been identified, and risk-avoidance advocated. These neglected zoonoses are mainly maintained in animal reservoir; hence their control/elimination is possible only through interventions that extensively target animal reservoirs accompanied by public enlightenment and information. This underscores the need for collaborations and partnerships between stakeholders in the Ministries of Agriculture, Health and Information for the enhancement of the health of both human and animal populations

Comparison of the Fluorescent Antibody Test and Direct Microscopic Examination for Rabies Diagnosis at the National Veterinary Research Institute, Vom, Nigeria.

One hundred and eighty-nine (189) dog brain samples submitted to the National Veterinary Research Institute, Vom, Nigeria for rabies diagnosis were assayed by the Direct Microscopic Examination (DME) for Negri bodies, the Fluorescent Antibody Test (FAT) for rabies antigens, and the Mouse Inoculation Test (MIT). The MIT was used as a confirmatory test. There were 12(12.5%) false negative and 6(6.7%) false positive results with DME, while there was 2(1.7%) false negative and 2(1.7%) false positive with FAT. The FAT was more sensitive (98.26%) than the DME (87.5%), and also more specific, 97.29% and 93.55% respectively. The FAT predicted positive and negative results more accurately than the DME. Positive predictive value of FAT was 98.26% compared with 93.33% of DME, and the negative predictive value of FAT was 97.29% compared with DME’s 87.88%. The pre-test probability of rabies in Vom was 60.8%. This finding shows that FAT is a sensitive and reliable rabies diagnostic test than DME and its continued use is recommended in Nigeria whenever is feasible. The DME is still useful as a screening test, and the MIT must be used to confirm both FAT and DM

Complex Circulation of Foot-and-Mouth Disease Virus in Cattle in Nigeria.

Nigeria is a large densely populated country in West Africa. Most of its livestock is raised in a pastoralist production system with typical long distance migration in search of water and feed. As the demand for animal products largely exceeds the domestic production, large numbers of livestock are imported from neighboring countries without sanitary restrictions. In Nigeria, foot-and-mouth disease virus (FMDV) serotypes O, A, and Southern African Territories (SAT)2 are endemic for a long time. Clinical outbreaks of FMD due to serotype SAT1 are described again since 2015, after an absence of more than 30 years. Historically, outbreaks of FMD due to serotypes O, A, SAT1, and SAT2 were each time associated with trade of cattle entering Nigeria from neighboring countries. In the present study, tissue samples from 27 outbreaks of FMD were collected in Nigerian cattle from 2012 until 2017 in six different States and in the Federal Capital Territory. FMDV was isolated and serotyped and further characterized by VP1 sequencing and phylogenetic analysis to gain more knowledge on FMDV circulation in Nigeria. Half of the outbreaks were characterized as FMDV topotype O/EA-3, while outbreaks with other serotypes and topotypes were-in descending order-less prevalent: A/Africa/G-IV, SAT1/X, SAT2/VII, and O/WA. The high dynamics and omnipresence of FMD in Nigeria were illustrated in Plateau State where FMDV serotypes O, SAT1, and SAT2 were isolated during the course of the study, while at some point in the study, outbreaks due to FMDV serotype A were observed in three remote States. The genetic and phylogenetic analysis suggests a mixed origin of FMD outbreaks. Some outbreaks seem to be caused by sustained local transmission of FMDV strains present in Nigeria since a number of years, while other outbreaks seem to be related to recent incursions with new FMDV strains. The role of African buffaloes in the etiology of FMD in Nigeria is unclear, and sampling of wildlife is needed. The results of the present study suggest that systematic sample collection is essential to understand the complex concomitance of FMDV strains in Nigeria and essential to support the implementation of a vaccination-based control&nbsp;plan.</p

Foot-and-mouth disease virus serotype SAT1 in cattle, Nigeria.

&lt;p&gt;The knowledge of foot-and-mouth disease virus (FMDV) dynamics and epidemiology in Nigeria and the West Africa subregion is important to support local and regional control plans and international risk assessment. Foot-and-mouth disease virus serotype South African territories (SAT)1 was isolated, identified and characterized from an FMD outbreak in cattle in Nigeria in 2015, 35 years after the last report of FMDV SAT1 in West Africa. The VP1 coding sequence of the Nigerian 2015 SAT1 isolates diverges from reported SAT1 topotypes resulting in a separate topotype. The reporting of a novel FMDV SAT1 strain in the virus pool 5 (West and Central Africa) highlights the dynamic and complex nature of FMDV in this region of Africa. Sustained surveillance is needed to understand the origin, the extent and distribution of this novel SAT1 topotype in the region as well as to detect and monitor the occurrence of (re-)emerging FMDV strains.&lt;/p&gt;</p

Detection and Molecular Characterization of Foot and Mouth Disease Viruses from Outbreaks in Some States of Northern Nigeria 2013-2015.

&lt;p&gt;Control measures for foot and mouth disease (FMD) in Nigeria have not been implemented due to the absence of locally produced vaccines and risk-based analysis resulting from insufficient data on the circulating FMD virus (FMDV) serotypes/strains. In 2013-2015, blood and epithelial samples were collected from reported FMD outbreaks in four states (Kaduna, Kwara, Plateau and Bauchi) in northern Nigeria. FMDV non-structural protein (NSP) seroprevalence for the outbreaks was estimated at 80% (72 of 90) and 70% (131 of 188) post-outbreak. Antibodies against FMDV serotypes O, A, SAT1, SAT2 and SAT3 were detected across the states using solid-phase competitive ELISA. FMDV genome was detected in 99% (73 of 74) of the samples from FMD-affected animals using rRT-PCR, and cytopathic effect was found in cell culture by 59% (44 of 74) of these samples. Three FMDV serotypes O, A and SAT2 were isolated and characterized. The phylogenetic assessments of the virus isolates showed that two topotypes of FMDV serotype O, East Africa-3 (EA-3) and West Africa (WA) topotypes were circulating, as well as FMDV strains belonging to the Africa genotype (G-IV) of serotype A and FMDV SAT2 topotype VII strains. While the serotype O (EA-3) strains from Nigeria were most closely related to a 1999 virus strain from Sudan, the WA strain in Nigeria shares genetic relationship with three 1988 viruses in Niger. The FMDV serotype A strains were closely related to a known virus from Cameroon, and the SAT2 strains were most closely related to virus subtypes in Libya. This study provides evidence of co-occurrence of FMDV serotypes and topotypes in West, Central, East and North Africa, and this has implication for control. The findings help filling the knowledge gap of FMDV dynamics in Nigeria and West Africa subregion to support local and regional development of vaccination-based control plans and international risk assessment.&lt;/p&gt;</p

Complete Genome Sequences of Five Foot-and-Mouth Disease Viruses of Serotype A Isolated from Cattle in Nigeria between 2013 and 2015.

The complete genome sequences of 5 foot-and-mouth disease viruses of serotype A are reported here. These viruses originate from outbreaks in northern Nigeria in 2013 to 2015 and belong to the A/AFRICA/G-IV&nbsp;lineage.</p

Complete Genome Sequences of Five Foot-and-Mouth Disease Viruses of Serotype A Isolated from Cattle in Nigeria between 2013 and 2015

The complete genome sequences of 5 foot-and-mouth disease viruses of serotype A are reported here. These viruses originate from outbreaks in northern Nigeria in 2013 to 2015 and belong to the A/AFRICA/G-IV&nbsp;lineage.</p

Molecular characterization of a rabies virus isolated from trade dogs in Plateau State, Nigeria

To have a better understanding of the prevalence of rabies virus (RABV) in the dog trading markets in Plateau State of Nigeria, a total of 532 brain samples collected between 2010 and 2011 were subjected to rabies virus antigen detection and molecular characterization. RABV antigen was detected in 92 out of 532 (17.3%) brain samples from two major commercial dog markets in Plateau State of Nigeria by direct fluorescence antibody assay, indicating the possibility of a high prevalence of RABV in the dog trading markets. The complete genomic sequence was obtained from one of these RABV positive samples. The overall organization of this virus (DRV-NG11) was typical of all the other wild-type RABV. Phylogenetic analysis using either the complete or partial genomic sequence of DRV-NG11 demonstrates that this isolate is most closely related to viruses previously shown to circulate in Nigeria, belonging to the Africa 2 Clade. To our knowledge, this is the first report on the molecular characterization of the complete genome of RABV from trade dogs, which provides a better understanding of the molecular epidemiology, pathogenesis and rabies control in this country.Keywords: Genome, Nigeria, Rabies virus, Street strain, Trade dog