Victor Oluwatoyin Akinseye

Evaluation of hepatotoxicity and clastogenicity of carbofuran in male Wistar rats

Carbofuran based pesticides have gained wide usage in Nigeria recently. Consequently, animals and human populations are exposed to them in the environment. Information on in vivo toxicity of carbofuran in experimental models is scanty. The present study therefore examined the hepatotoxicity and clastogenic effects of carbofuran in rats. Male Wistar rats were exposed to carbofuran (p.o) at 0-5mg/kg bw for 5weeks. Carbofuran induced significant (p<0.05) increase in the serum activity of gamma-glutamyltransferase when compared with the negative control, but not activity of serum alanine and aspartate aminotransferases. It also significantly (p<0.05) induced micronucleated polychromatic erythrocytes formation in the bone marrow as compared with the control. The level of induction is dose dependent in both cases. In addition, there was significant (p<0.05) higher number of hepatic cells in the cell/mm(2) assay for the group treated with carbofuran. Histopathological analysis of liver samples from the treated groups revealed lesions ranging from general congestion (portal, central venous and sinusoidal), mild periportal cellular infiltration, diffused sinusoidal congestion and hepatic necrosis to severe congestion. Findings from this study suggest that carbofuran has clastogenic and hepatotoxic effects in rats. It therefore may constitute an environmental health risks in individuals so exposed.

Gastrointestinal Helminths in Slaughtered Cattle in Ibadan, South-Western Nigeria

As part of an ongoing project to investigate the epidemiology of gastrointestinal helminths of cattle in Nigeria, we carried out a systematic random sampling of cattle slaughtered in a major abattoir in Ibadan, south-western Nigeria. Using sedimentation and floatation methods, we analyzed fecal samples from 397 animals between March and May 2013. Overall, 163 (41.6%) of the animals had at least one gastrointestinal helminth egg, comprising a total of eight helminths from different genera (i.e., four nematodes, three trematodes, and one cestode), with nematode infection being the highest (71.54%). In addition, eggs of four helminths of zoonotic importance were also obtained. Among the cattle examined, the Bunaji breed was the most infected (46%; 69/150). Furthermore, female animals (OR = 1.1; 95% CI: 0.60–1.84) and animals with moderate body condition (OR = 1.2; 95% CI: 0.80–1.79) are more likely to be positive to helminth infection. Our findings reveal that there were helminth infections of both zoonotic and socioeconomic importance among the cattle screened. Considering the impact of the infections on animal production and public health, we advocate that effective prophylactic measures be adopted as a first step to curtail helminth infections of cattle in Nigeria.

Prevalence of bovine brucellosis in slaughtered cattle and barriers to better protection of abattoir workers in Ibadan, South-Western Nigeria

Introduction Brucellosis is a neglected zoonosis of public health importance. This study was conducted to determine the prevalence and risk factors of brucellosis among slaughtered cattle as well as challenges to the protection of abattoir workers in Nigeria. Methods A slaughterhouse study was conducted in a major abattoir in Ibadan from March to August, 2013. To diagnose brucellosis, serum samples from 1,241 slaughtered cattle were tested using Rose-Bengal test (RBT) and competitive enzyme-linked immunosorbent assay (cELISA); again, 57 milk samples were tested with milk ring test (MRT) and indirect ELISA (iELISA). Furthermore, a survey on the usage of personal protective equipment (PPE) and challenges to its use by abattoir workers was done. Data were analysed using Stata 12. Results Seroprevalence by RBT was 7.8%; 77.3% (75/97) of these were corroborated by cELISA. Prevalence in milk samples by MRT and indirect ELISA were 33.3% and 3.5%, respectively. Sex (OR: 2.5; 95%CI:1.3-4.5) was the factor significantly associated with Brucella seropositivity. None of the abattoir workers used standard protective overalls; while, 99.6% of the meat handlers and 84.1% of the butchers worked barefoot. Most of the workers (75.7%) wore no protective gloves. The respondents agreed that provision of free PPE and sanctions against non-users would encourage its use. Conclusion Our findings indicate moderate prevalence (7.8%) of bovine brucellosis with sex of cattle being a risk factor. A notable barrier to better protection of abattoir workers against brucellosis is perceived inconvenience arising from use of gloves. Therefore, preventive and control measures against brucellosis must include education and use of PPE among abattoir workers.

Sero-epidemiological survey and risk factors associated with brucellosis in dogs in south-western Nigeria.

Introduction In Nigeria, there is limited information on brucellosis particularly in dogs, despite its public health implications. We undertook a sero-epidemiological survey of brucellosis in dogs to determine the prevalence of the disease and associated risk factors for its occurrence in Nigeria. Methods A cross-sectional study was conducted to screen dogs in south-western Nigeria for antibodies to Brucella sp using the rapid slide agglutination test (RSA) and Rose Bengal test (RBT), with positive samples confirmed respectively by serum agglutination test (SAT) and competitive enzyme linked immunosorbent assay (cELISA). Data were analyzed with STATA-12. Results From the 739 dog sera tested, 81 (10.96%) were positive by RSA and 94 (12.72%) by RBT; these were corroborated with SAT (4/81; 4.94%) and cELISA (1/94; 1.06%), respectively. Logistic regression identified location (OR=0.04; 95% CI: 0.02-0.09), breed (OR=1.71; 95% CI: 1.34-2.19), age (OR=0.10; 95% CI: 0.04-0.30) and management system (OR=8.51; 95% CI: 1.07-68.05) as risk factors for Brucella infection by RSA. However, location (OR=10.83; 95% CI: 5.48-21.39) and history of infertility (OR=2.62; 95% CI: 1.41-4.84) were identified as risk factors using RBT. Conclusion Given the 10.96% to 12.72% seroprevalence of brucellosis recorded in this study, we advocate control of the disease in dogs, and public health education for those at risk of infection. Again, further studies are required to elucidate the role of dogs in the epidemiology of brucellosis in Nigeria considering the conducive human-animal interface and ecological factors responsible for the transmission of the disease.

Prevalence and risk factors associated with bovine brucellosis in herds under extensive production system in southwestern Nigeria

Using a cross-sectional survey, we determined the prevalence and risk factors associated with bovine brucellosis in herds under extensive production system in southwestern Nigeria. Antibodies to Brucella species in serum samples were tested using the Rose Bengal test (RBT) and competitive enzyme-linked immunosorbent assay (cELISA); for milk, the milk ring test (MRT) and indirect-ELISA (i-ELISA) were used. Questionnaire was administered to cattle herdsmen to determine factors predisposing the animals to bovine brucellosis. Data were analyzed using STATA 12. From 513 serum and 635 milk samples tested among 120 herds, overall animal-level prevalence of 10.1% (95% CI 7.5–12.7%) and 20.2% (95% CI 17.1–23.3%) were recorded by RBT and MRT, respectively; while 9.4% (95% CI 6.9–11.9%) and 17.8% (95% CI 14.8–20.8%) were obtained using cELISA and i-ELISA, respectively. In all, from the 120 herds tested, 29.2% and 43.3% were positive by RBT and MRT, respectively. Multivariable logistic regression revealed that herd location (OR = 8.12, 95% CI 1.68–38.90) and improper disposal of placenta/fetus (OR = 17.33, 95% CI 4.81–62.33) were predictors for a seropositive herd using RBT; while herd location (OR = 5.13, 95% CI 1.27–20.28), large herd size (OR = 2.62, 95% CI 1.15–5.85), and occurrence of abortion for a year or more (OR = 4.62, 95% CI 1.53–13.71) were predictors of seropositivity to antibodies to Brucella spp. using MRT. We found high prevalence of brucellosis in cattle herds under extensive management system in southwestern Nigeria. Urgent and coordinated control strategies are required to mitigate this problem.

Perception and incidence of Buruli ulcer in Ogun State, South West Nigeria: intensive epidemiological survey and public health intervention recommended

Introduction Buruli ulcer (BU) is a highly ranked neglected tropical disease (NTD) of global health importance with increasing incidence in sub-Saharan Africa yet there is paucity of information on the epidemiology of BU in Nigeria. Incidentally, highly BU endemic Benin Republic shares proximity with Nigeria. This study was carried out to establish presence of BU and ascertain the level of BU perception among rural populace in Ogun State, south-west Nigeria. Methods Secondary data (2009-2012) on incidence of BU was collected from a reference hospital. A cross-sectional survey using structured questionnaire administered to rural people and healthcare practitioners was conducted in three purposively chosen Local Government Areas (LGAs) in Ogun State based on unpublished reports of BU presence. Results Data collected revealed 27 hospital confirmed BU cases between 2009-2012 across four LGAs (Obafemi Owode, Abeokuta North, Yewa North and Yewa South) while 14%(21/150) chronic ulcers (suspected to be BU) were discovered during the cross-sectional survey carried out in Odeda, Yewa South and North LGAs. Healthcare practitioners 63.6% (42/66) and 54.7% (82/150) rural people demonstrated poor level of BU perception respectively. Conclusion This study provides evidence that BU exists in Ogun State and evaluates the poor perception that the affected rural populace has on the disease. This pilot study presents baseline information on BU in a rural setting in Ogun State South-west Nigeria hence the vital need for prompt public health involvement and further research on the epidemiology of BU.

Knowledge and practices about zoonotic tuberculosis prevention and associated determinants amongst livestock workers in Nigeria; 2015

Zoonotic tuberculosis (TB) is a significant public health disease, but has long been neglected. Information on knowledge and practices of its prevention and influencing factors amongst occupationally exposed individuals is required for designing all-inclusive, informed control programmes. We investigated knowledge and practices related to zoonotic TB prevention and associated determinants amongst herdsmen and abattoir workers in south-western, south-eastern and north-western Nigeria using semi-structured questionnaire. Data were analysed with STATA 12. A total of 510 respondents (196 herdsmen; 314 abattoir workers) participated in the survey, of which 58.6% and 46.9% respectively were knowledgeable and demonstrated good practices about zoonotic TB prevention. Almost 60% knew that zoonotic TB transmission was preventable and 49.8% knew transmission could be through consumption of infected animal products. However, only 16.7% knew the disease could be transmitted by aerosol. Just 49.4% sought medical check-up when ill, 37.8% used protective clothing and only 29.2% usually condemned TB infected cattle. Respondents with post-primary education were about three times more likely to be knowledgeable (OR = 2.70, 95%CI: 1.68–4.33) and two times more likely to demonstrate good practice (OR = 2.23, 95%CI: 1.45–3.42) than those without formal education. Similarly, abattoir workers were about 6.4 times more likely to be knowledgeable (OR: 6.39, 95%CI: 4.31–9.47) and two times more likely to demonstrate good practice (OR: 2.03, 95%CI: 1.40–2.92) than the herdsmen. There were important knowledge gaps with poor practices about zoonotic TB prevention amongst livestock workers in Nigeria. Strong predictors of knowledge and practice were being an abattoir worker and having post-primary education. Well-designed grassroots enlightenment programmes addressing modes of transmission, handling infected cattle and seeking medical check-up are urgently needed among high risk settings considering the recently launched Road Map for Zoonotic Tuberculosis which resonates that every tuberculosis case counts towards 2030 End-TB Strategy.

Isolation of Mycobacterium tuberculosis from livestock workers and implications for zooanthroponotic transmission in Ibadan, South-western Nigeria

Summary Introduction Tuberculosis (TB) remains a public health problem in sub-Saharan Africa coupled with dearth of information about the disease among livestock workers at risk of infection. We determined the prevalence of pulmonary TB infection and factors associated with its occurrence among livestock workers in south-western Nigeria. Methods A cross-sectional study was conducted using active case-finding among livestock workers with sub-clinical pulmonary TB between August 2014 and March 2015. Sputum samples were cultured and subjected to a two-step multiplex-PCR technique based on genus-typing and genomic regions-of-difference. Interviewer-administered questionnaire was utilized in assessing worker’s TB related knowledge and practices. Data were analysed using STATA 12. Results Overall, 206 livestock workers (traders = 136; butchers = 70) were screened; 5.1% (7/136) of the traders and 7.1% (5/70) of the butchers had positive mycobacterial cultures. Molecular techniques identified one Mycobacterium tuberculosis with six non-tuberculous mycobacteria (NTM) from the traders and four M. tuberculosis with one NTM from the butchers.Participants within the age range of 50 years and above were at higher risk of being infected with TB (OR = 7.7; 95%CI:1.7-35.6) and majority had poor knowledge and practices regarding TB. Conclusions We confirmed M. tuberculosis as the cause of pulmonary TB among the livestock workers, with implications for zooanthroponotic transmission of the disease along the human-animal ecosystem interface in Nigeria.

SEROLOGICAL SURVEY OF TOXOPLASMOSIS, NEOSPOROSIS AND BRUCELLOSIS AMONG CATTLE HERDS IN OYO STATE, SOUTH-WESTERN NIGERIA

Background: Several zoonotic diseases are known to constitute great impediment to livestock management and production worldwide, especially in developing countries where control measures are largely non-existent. This study sets out to investigate the occurrence of toxoplasmosis, neosporosis and brucellosis among cattle herds in Oyo State, southwest Nigeria. Materials and Methods: A cross-sectional survey to screen for antibodies to Toxoplasma gondii, Neospora caninum and Brucella abortus was conducted among 174 cattle in 17 herds. Sera obtained from the cattle were screened for antibodies to Toxoplasma gondii and Neospora caninum using enzyme-linked immunosorbent assay (ELISA) and for Brucella abortus antibodies using Rose Bengal test and Competitive Enzyme Linked Immunosorbent Assay (cELISA). Results: Overall, herd level prevalence of 52.9%, 23.5% and 23.5% as well as individual prevalence of 7.5%, 3.4% and 3.4% was obtained for toxoplasmosis, neosporosis and brucellosis, respectively. Antibodies to T. gondii, N. caninum and B. abortus were detected in 2 of the 17 herds, T. gondii and N. caninum in 4 herds, and T. gondii and B. abortus in 4 herds. Statistically significant association was only found between seropositivity to T. gondii antibodies and sex (p<0.05). Conclusion: Our results showed that toxoplasmosis, neosporosis and brucellosis are prevalent among cattle herds screened in the study area. Considering the potential impact of these diseases on livestock management and production, extensive surveillance is necessary for development and implementation of effective control and prevention strategies.