Seromolecular surveillance of rabbit haemorrhagic disease virus in Nigeria.

Following the first 2020 rabbit haemorrhagic disease virus (RHDV) outbreak in Nigeria which caused massive mortalities in several rabbitries, there was a need to know the spread and strains circulating in the affected states. Over 100 rabbitries still existing post-RHDV outbreak in Ogun and Kwara States were investigated. A commercial enzyme-linked immunosorbent assay kit was used to screen for RHDV immunoglobulin G in 192 rabbit sera, while RHDV VP60 gene was amplified in RNA extracted from these sera and tissues (liver and/or spleen harvested from 37 carcasses necrotized) by reverse transcription-polymerase chain reaction (RT-PCR). Sequences obtained from the amplicons were subjected to phylogenetic analysis. The results revealed a seroprevalence of 82.3% (158/192). RHDV VP60 gene was detected in 15/17 (88.2%) and 2/20 (10.0%) carcasses from Ogun and Kwara States, respectively, while none of the sera was positive. Sequences of the two positive amplicons selected (one from each states) shared 98.95% nucleotide identity and belonged to RHDV 2/GI.2 strain. Also, nBLAST of these sequences revealed 98.43-99.55% homology with the prototype Nigerian RHDV strain RHDV/NGR/ILN/001 (MT996357.1). Furthermore, these strains clustered with this prototype and a German RHDV strain (LR899166.1). Pathologic lesions affecting the respiratory, cardiovascular, renal, lymphatic, and digestive systems were observed in necropsied carcasses. This study indicated that RHDV 2/GI.2 strain was the cause of 2020 RHD outbreak in Nigeria. Thus, while continuous public sensitization about RHD especially among rabbit farmers in Nigeria is important, efforts aimed at design and implementation of RHD vaccination policy, preferably using indigenous seed, should be expedited.

Epidemiology and public health implications of parasitic contamination of fruits, vegetables, and water in Kwara Central, Nigeria.

Fruits and vegetables are sources of parasitic infections in humans. This study was designed to determine the epidemiology of parasitic contamination of fruits, vegetables, and water, as well as the perception of retailers, buyers, and consumers about its contamination in Kwara Central, Nigeria. A cross-sectional study design was employed for this study. A total of 160 fruits, 349 vegetables, and 51 water samples were randomly purchased/collected from thirty different markets. The samples were subjected to sedimentation and modified Ziehl-Neelsen staining techniques. All the types of fruits and vegetables sampled were contaminated with one or more parasites. Eleven different species of zoonotic parasites (6 protozoans and 5 helminths) were detected. Entamoeba coli (39.8%) and Strongyloides stercoralis (9.6%) were the most prevalent protozoan and helminth respectively. The prevalence of other protozoan parasites ranged between 21.3% (Entamoeba histolytica) and 2.3% (Balantidium coli), while that of helminths was between 5.7% (Ascaris lumbricoides) and 2.1% (Trichuris trichiura). Source of fruits and vegetables, source of manure for cultivation, the source of water for washing/wetting purpose, market type, washing of fruits and vegetables before display, the presence of children at home and in the market, and knowledge of parasitic contamination were the risk factors associated (P<0.05) with parasitic contamination of fruits and vegetables among sellers. There is a need to educate the general public on the possibilities of parasitic contamination of fruits and vegetables and its public health implications.

Neglected zoonotic diseases in Nigeria: role of the public health veterinarian.

Zoonotic diseases accounts for about 75% of emerging infectious disease and can be devastating to both human and animal health globally. A subset of zoonotic diseases is referred to as "neglected zoonotic diseases - NZDs" as they mainly affect poor populations who live in close proximity to domestic or wild animals often in areas where access to health and adequate sanitary facilities are not available. Furthermore, underestimation of the burden of NZD has continually led to its further neglect in least developed countries such as Nigeria. Controlling zoonotic infections including NZDs in animals is crucial in reducing human infections. Veterinarians provides an understanding of the epidemiology of infectious diseases in animal population and are therefore integral for the overall reduction in global burden of NZDs worldwide. Due to the current lack of and in some cases weak involvement of Veterinarians in policy issues related to zoonotic diseases, there is need to elucidate their importance in NZDs control in Nigeria. This review therefore summarises the neglected zoonotic diseases so far documented in Nigeria and also highlight the important role of the Veterinarian in their prevention and control within both human and animal population. Important recommendations to strengthen the role of the public health Veterinarian for sustainable control of NZDs were made.

Awareness and antibody detection of Newcastle disease virus in a neglected society in Nigeria.

AIMS: This study aimed to assess the level of awareness of rural poultry farmers on vaccination and to detect Newcastle disease virus (NDV) antibody in local birds (LB) and eggs in Kwara State, Nigeria. MATERIALS AND METHODS: Data on farmers' attitude, knowledge, practices, and experiences on ND mortality were obtained through an interview using a structured cross-sectional checklist. NDV antibodies were detected in sera and egg yolks of local chickens (LC) and guinea fowls (GF) using hemagglutination inhibition test. RESULTS: A total of 83 interviewees, 287 sera and 121 egg yolk extracts, were examined. The study revealed that 98.8% (82/83) of the interviewee had never vaccinated their flock before. 90% of the interviewee had reported high mortality in birds within 1-6 months old, while the major clinical signs were cold (40.4%) and torticollis (30.8%). Evidences of LB exposure to wild-type NDV were confirmed by the detection of NDV antibodies in 20.8% and 0% of LC and GF, respectively. The mortality differences experiencedin <1 and 1-6 months old LB could be explained by the presence of maternally-derived NDV antibody (49.6%) in egg yolk. CONCLUSION: The study showed that LB suffers from NDV as a result of LB keepers' ignorance and neglect by the government. This has limited local investment and subsequent contribution to gross domestic product. This study suggests that the key factors to the prevention of ND remain awareness creation about poultry vaccination, production of affordable vaccines, and availability/accessibility to veterinarian (or trained personnel).

Assessment of antibody assay methods in determination of prevalence of infectious bursal disease among local chickens and guinea fowls in Kwara state, North Central Nigeria.

AIM: This study aimed to assess available assay methods for infectious bursal disease (IBD) diagnosis and seromonitoring in local birds. It also sought to know the prevalence of IBD antibodies among local chickens and guinea fowls in Kwara state, North Central Nigeria. MATERIALS AND METHODS: Sera were obtained from local chickens and guinea fowls and IBD virus (IBDV) antibodies were assayed using enzyme-linked immunosorbent assay (ELISA), indirect hemagglutination (IHA) test, and agar gel immunodiffusion (AGID) test. RESULTS: A total of 265 sera were obtained from local birds during dry and wet seasons. ELISA recorded the highest prevalence of 81.1% (215/265) while IHA and AGID detected IBDV antibodies in 183 (69.1%) and 122 (46%) birds, respectively. Significant differences were established for IBD-positive sera based on the assay method used, bird species, and seasons. CONCLUSION: This study indicated that ELISA is the most sensitive and reliable assay method while AGID is the least. It also showed that there is a high prevalence of IBDV antibodies among local birds which were not vaccinated, and this implies a high IBDV activity among these bird species in the study area. This may have significant epidemiological implications on the spread of the virus to exotic bird reared in the rural areas on a commercial scale. Thus, this study suggests continuous surveillance, awareness campaign, and advocacy for vaccination of indigenous birds against IBD.