Background
In Nigeria, there have been reports of widespread multiple antimicrobial resistance (AMR) amongst
Salmonella
isolated from poultry. To mitigate the impact of mortality associated with
...Salmonella
on their farms, farmers resort to the use of antimicrobials without sound diagnostic advice. We conducted this study to describe the AMR patterns, mechanisms and genetic similarities within some
Salmonella
serovars isolated from different layer farms.
Method
We determine the AMR profiles of two hundred
Salmonella
isolates, selected based on frequency, serovar, and geographical and sample type distribution. We also assessed the mechanisms of multi-drug resistance for specific genetic determinants by using PCR protocols and gene sequence analysis. Pulsed-field gel electrophoresis (PFGE) was conducted on seven selected serovars to determine their genetic relatedness.
Results
Of 200 isolates, 97 (48.5%) revealed various AMR profiles, with the multiple antibiotic resistance (MAR) index ranging from 0.07–0.5. Resistance to ciprofloxacin was common in all the multi-drug resistant isolates, while all the isolates were susceptible to cefotaxime, ceftazidime, and meropenem. Genotypic characterization showed the presence of resistance genes as well as mutations in the nucleotide genes with subsequent amino acid substitutions. Fifteen isolates (43%) of
S
. Kentucky were indistinguishable, but were isolated from four different states in Nigeria (Ogun, n = 9; Kaduna, n = 6; Plateau, n = 3, and: Bauchi, n = 2). PFGE revealed 40 pulsotype patterns (Kentucky, n = 12; Larochelle, n = 9; Virchow, n = 5; Saintpaul, n = 4; Poona, n = 3; Isangi, n = 2, and; Nigeria, n = 2).
Conclusion
This study recorded strictly related but diversely distributed
Salmonella
serovars with high AMR rates in poultry. We recommend strict regulation on antimicrobial use and regular monitoring of AMR trends among bacteria isolated from animals and humans to inform public policy.
The need for a reliable risk map in the control of soil-transmitted helminths (STHs) in Kogi East, North Central Nigeria is very important. This study was carried out to determine the effect of ...environmental risk factors on geospatial distribution of STHs. Epidemiological data were obtained from a district-wide survey conducted in 2018 in Kogi East. Edaphic and climatic factors were downloaded as spatial layers from international recognised health data resources centres. A total of 24 environmental factors were used in determining the risk map of STHs using MaxEnt tool. The predicted high-risk areas of A. lumbricoides, hookworms and S. stercoralis were the central part of Kogi East covering parts of Dekina, Ofu, Igalamela-Odolu, Olamaboro and Omala LGAs with probability of 0.8 to 1.00. Among the factors investigated; Temperature mean diurnal temperature range (BIO2), temperature annual range (BIO7) and maximum temperature of the warmest month (BIO5), precipitation precipitation of the wettest quarter (BIO16), and soil clay contents were the five factors that exerted most significant influence on the geospatial distribution of STHs in Kogi East, Nigeria. Public health control programmes on STHs should target high-risk areas by including them in mass drug administration, health education as well as provision of water, sanitation and hygiene infrastructures.
Commercial poultry farms (n° 523), located in all the six regions of Nigeria were sampled with a view to generate baseline information about the distribution of Salmonella serovars in this country. ...Five different matrices (litter, dust, faeces, feed and water) were collected from each visited farm. Salmonella was isolated from at least one of the five matrices in 228 farms, with a farm prevalence of 43.6% (CI9539.7-48.3%). Altogether, 370 of 2615 samples collected (14.1%, CI9512.8; 15.5%) contained Salmonella. Considering the number of positive farms and the number of positive samples, it was evident that for the majority of the sampled farms, few samples were positive for Salmonella. With regard to the matrices, there was no difference in Salmonella prevalence among the five matrices considered. Of the 370 isolates serotyped, eighty-two different serotypes were identified and Salmonella Kentucky was identified as having the highest isolation rate in all the matrices sampled (16.2%), followed by S. Poona and S. Elisabethville. S. Kentucky was distributed across the country, whereas the other less frequent serovars had a more circumscribed diffusion. This is one of few comprehensive studies on the occurrence and distribution of Salmonella in commercial chicken layer farms from all the six regions of Nigeria. The relatively high prevalence rate documented in this study may be attributed to the generally poor infrastructure and low biosecurity measures in controlling stray animals, rodents and humans. Data collected could be valuable for instituting effective intervention strategies for Salmonella control in Nigeria and also in other developing countries with a similar poultry industry structure, with the final aim of reducing Salmonella spread in animals and ultimately in humans.
Tsetse flies are cyclical vectors of African trypanosomiasis (AT). The flies have established symbiotic associations with different bacteria that influence certain aspects of their physiology. Vector ...competence of tsetse flies for different trypanosome species is highly variable and is suggested to be affected by bacterial endosymbionts amongst other factors. Symbiotic interactions may provide an avenue for AT control. The current study provided prevalence of three tsetse symbionts in Glossina species from Cameroon, Chad and Nigeria.
Tsetse flies were collected and dissected from five different locations. DNA was extracted and polymerase chain reaction used to detect presence of Sodalis glossinidius, Spiroplasma species and Wolbachia endosymbionts, using species specific primers. A total of 848 tsetse samples were analysed: Glossina morsitans submorsitans (47.52%), Glossina palpalis palpalis (37.26%), Glossina fuscipes fuscipes (9.08%) and Glossina tachinoides (6.13%). Only 95 (11.20%) were infected with at least one of the three symbionts. Among infected flies, six (6.31%) had Wolbachia and Spiroplasma mixed infection. The overall symbiont prevalence was 0.88, 3.66 and 11.00% respectively, for Sodalis glossinidius, Spiroplasma species and Wolbachia endosymbionts. Prevalence varied between countries and tsetse fly species. Neither Spiroplasma species nor S. glossinidius were detected in samples from Cameroon and Nigeria respectively.
The present study revealed, for the first time, presence of Spiroplasma species infections in tsetse fly populations in Chad and Nigeria. These findings provide useful information on repertoire of bacterial flora of tsetse flies and incite more investigations to understand their implication in the vector competence of tsetse flies.
West Nile virus (WNV) causes a mosquito-borne zoonotic disease of public health importance. The aim of this study was to determine the state of WNV infection in horses and detect the virus antigen in ...mosquitoes trapped in stables in Kaduna State Nigeria. The study was carried out in Kaduna State, Nigeria, and 368 horses were screened for the presence of antibodies against WNV using an IgG competitive enzyme-linked immunosorbent assay. Of the 368 samples tested, 331 (89.9%) were positive for WNV antibodies. Mosquitoes from the stables were tested for WNV antigen using a VectorTest kit, and of the 31 pools of adult mosquitoes tested, only 5 (16.1%) pools tested positive for WNV antigen. This finding showed that WNV infection has occurred in horses and that there is evidence of circulation of the virus by mosquitoes in Kaduna State, Nigeria.
Toxoplasma gondii parasites present strong but geographically varied signatures of population structure. Populations sampled from Europe and North America have commonly been defined by ...over-representation of a small number of clonal types, in contrast to greater diversity in South America. The occurrence and extent of genetic diversity in African T. gondii populations remains understudied, undermining assessments of risk and transmission. The present study was designed to establish the occurrence, genotype and phylogeny of T. gondii in meat samples collected from livestock produced for human consumption (free-range chickens, n = 173; pigs, n = 211), comparing with T. gondii detected in blood samples collected from seropositive pregnant women (n = 91) in Benue state, Nigeria. The presence of T. gondii DNA was determined using a published nested polymerase chain reaction, targeting the 529 bp multicopy gene element. Samples with the highest parasite load (assessed using quantitative PCR) were selected for PCR-restriction fragment length polymorphism (PCR-RFLP) targeting the surface antigen 3 (SAG3), SAG2 (5' and 3'), beta-tubulin (BTUB) and dense granule protein 6 (GRA6) loci, and the apicoplast genome (Apico). Toxoplasma gondii DNA was detected in all three of the populations sampled, presenting 30.6, 31.3 and 25.3% occurrence in free-range chickens, pigs and seropositive pregnant women, respectively. Quantitative-PCR indicated low parasite occurrence in most positive samples, limiting some further molecular analyses. PCR-RFLP results suggested that T. gondii circulating in the sampled populations presented with a type II genetic background, although all included a hybrid type I/II or II/III haplotype. Concatenation of aligned RFLP amplicon sequences revealed limited diversity with nine haplotypes and little indication of host species-specific or spatially distributed sub-populations. Samples collected from humans shared haplotypes with free-range chickens and/or pigs. Africa remains under-explored for T. gondii genetic diversity and this study provides the first detailed definition of haplotypes circulating in human and animal populations in Nigeria.
This study was carried out to investigate the status of brucellosis in cattle under various management systems in Adamawa, Kaduna and Kano states, northern Nigeria. Using multi-stage sampling, serum ...samples of 4,745 cattle from 271 herds were tested using the Rose-Bengal plate-agglutination test (RBPT) and positives were confirmed using a competitive enzyme-linked immunosorbent assay (c-ELISA).
Prevalence estimates were calculated by adjusting for sampling weights and where possible for test sensitivity and specificity. Thirty-seven percent of all animals were RBPT positive, and after confirmation with c-ELISA the overall animal-level prevalence, adjusted for sampling weights, was 26.3% (95% CI, 22.1%-31.0%). Of the herds sampled, 210 (77.5%; 95% CI, 68.6%-84.5%) had at least one animal positive to both tests; this did not differ significantly between states (P = 0.538). Mean within-herd seroprevalence in positive herds was 30.2% (95% CI, 25.3%-35.1%) and ranged from 3.1% to 85.7%. Overall animal-level seroprevalences of 29.2% (95% CI, 22.5%-36.9%) n = 1,827, 23.3% (95% CI, 18.9%-28.3%) n = 1,870 and 26.7% (95% CI, 18.8%-36.7%) n = 1,048 were observed in Adamawa, Kaduna and Kano states, respectively (P = 0.496). A significantly higher seroprevalence was found in males (38.2%; 95% CI, 31.7%-45.2%) than in females (24.7%; 95% CI, 20.4%-29.5%) (P < 0.001) and in non-pregnant females (27.8%; 95% CI, 22.9%-33.5%) than in pregnant females (17.2%; 95% CI, 13.6%-21.5%) (P < 0.001). Seroprevalence increased with increasing age (P < 0.001), from 13.5% (95% CI, 8.9%-19.9%) in cattle <4 years to 35.0% (95% CI, 28.5%-42.3%) in cattle >7 years. Seroprevalence also varied between management systems (P < 0.001): pastoral systems 45.1% (95% CI, 38.6%-51.9%), zero-grazing systems 23.8% (95% CI, 6.8%-59.2%), agro-pastoral systems 22.0% (95% CI, 17.3%-27.8%), and commercial farms 15.9% (95% CI, 9.5%-25.5%). Seroprevalence did not differ significantly between breeds or lactation status.
This is the first large study to assess the prevalence of bovine brucellosis over a wide geographic area of northern Nigeria, in a variety of management systems and using accurate tests. The seroprevalence of brucellosis was high, and higher than results of previous studies in northern Nigeria. The pastoral management systems of the traditional Fulanis may be encouraging the dissemination of the disease. Public enlightenment of the farmers about the disease, vaccination and appropriate national control measures are recommended.
Antimicrobial resistance (AMR) poses an important One Health challenge for all countries of the world. As human, animal and environmental health are closely linked, it is essential that interventions ...targeted at reducing the spread of AMR and those promoting antimicrobial stewardship are conducted with all sectors in mind. Tackling this global slow-moving pandemic (AMR) also requires action and strong commitment from all countries of the world. Nigeria, like many other countries, have made considerable progress in implementing the National Action Plan on Antimicrobial Resistance. The accomplishments and ongoing work led by the National Technical Working Group on AMR is commendable. However, gaps still exist in terms of operationalising One Health interventions for AMR, especially regarding rational antimicrobial use and antimicrobial stewardship. The 2020 World Antimicrobial Awareness Week presented an opportunity to convene a multi-sectoral expert panel from national government agencies, research, academia and the World Health Organisation across the Nigerian One Health space. The panel discussion analysed the progress made so far and identified the barriers and the opportunities for operationalising One Health interventions on AMR. The discussion highlighted poor awareness and the
phenomenon, driven by technical and socio-economic factors, as a common cross-sectoral denominator at the heart of inappropriate antibiotic use within the country. At the system level, suboptimal use of antimicrobials fuelled by the ease of purchase, poor regulations and insufficient enforcement of prescription-only access to antimicrobials, and limited infection prevention and biosecurity measures resonated as drivers of AMR across One Health sectors in Nigeria. Looking forward, the panel discussion identified substantial investment in the governance of the existing One Health component structures, inclusive bottom-up institutional antimicrobial stewardship that fosters community participation and multi-level cross-sectoral collaborations as the next level strategic imperatives. In this respect is the need for a strengthened One Health infrastructure, including an operational workforce, educational strategies to elevate AMR and rational antimicrobial use into public consciousness, and the use of improved data systems as countermeasures to the challenge of AMR.
Nigeria, with a population of over 190 million people, is rated among the 10 countries with the highest burden of infectious and zoonotic diseases globally. In Nigeria, there exist a sub-optimal ...surveillance system to monitor and track priority zoonoses. We therefore conducted a prioritization of zoonotic diseases for the first time in Nigeria to guide prevention and control efforts. Towards this, a two-day in-country consultative meeting involving experts from the human, animal, and environmental health backgrounds prioritized zoonotic diseases using a modified semi-quantitative One Health Zoonotic Disease Prioritization tool in July 2017. Overall, 36 of 52 previously selected zoonoses were identified for prioritization. Five selection criteria were used to arrive at the relative importance of prioritized diseases based on their weighted score. Overall, this zoonotic disease prioritization process marks the first major step of bringing together experts from the human-animal-environment health spectrum in Nigeria. Importantly, the country ranked rabies, avian influenza, Ebola Virus Disease, swine influenza and anthrax as the first five priority zoonoses in Nigeria. Finally, this One Health approach to prioritizing important zoonoses is a step that will help to guide future tracking and monitoring of diseases of grave public health importance in Nigeria.
•Nigeria is among the top ten countries with the highest burden of infectious and zoonotic diseases globally.•One Health approach resulted in prioritization of important zoonoses and will guide their future tracking and monitoring.•Rabies, avian influenza, Ebola Virus Disease, swine influenza and anthrax as the first five priority zoonoses in Nigeria.
This study was undertaken to investigate the status of Soil-transmitted Helminths (STHs) in rural schools of Kogi East, Nigeria. The study was cross-sectional using stratified random cluster sampling ...procedure. Stool specimens were collected in a sterile specimen bottle from school pupils in five (5) randomly selected schools in each of the nine Local Government Areas (LGAs) (45 schools) of Kogi East to enable complete epidemiological survey, all schools selected were located within the rural areas of the LGAs. Collected samples were preserved in 10% formalin and examined for parasites using formal ether sedimentation technique. Structured questionnaires were administered to obtain information on the risk factors associated with STHs. Data were analysed using descriptive statistics and Chi-square test was used to test the relationship in prevalence of STHs according to categories of infections. The overall prevalence of STHs in Kogi East was 17.1% with
Ascaris lumbricoides
, hookworms and
Strongyloides stercoralis
having prevalence of 4.3%, 12.7% and 1.1% respectively. Hookworms’ infection was the most widespread in Kogi East. Omala LGA (29.6%) had the highest prevalence of STHs. No significant difference (
p
> 0.05) in prevalence between male (18.2%) and female (16.0%) pupils, and between the age groups of 5–8 years (16.6%) and 9–12 years (17.8%). STHs is endemic among rural pupils of Kogi East as observed in the prevalence of infection as well as the prevailing risk factors, preventive chemotherapy is warranted. Therefore, school-based deworming alongside health education programme should be extended to rural schools.