6 research outputs found
Occurrence of community-acquired Panton-Valentine leukocidin-producing and enterotoxin-producing methicillin-resistant staphylococci in companion dogs
No full textIn Nigeria, available data on drug-resistant bacterial infections that are caused by companion dogs are scarce. Hence the present study evaluated the occurrence of some community-acquired toxigenic methicillin-resistant staphylococci (MRS) on companion dogs harboured in Nigerian homes, as a pointer to the extent of exposure of humans to these pathogens. Samples were collected from 70 healthy companion dogs during dry and rainy season periods by swabbing a 125 cm2 fur area on the lumbar and thoracic sites. Phenotypic tests, Kirby Bauer disc diffusion test and 16S rRNA gene analysis were used to identify presumptive colonies of staphylococci and MRS. Molecular methods were employed to detect Panton-Valentine leukocidin (PVL) and prototypic enterotoxin B in MRS isolates. The counts of staphylococci on fur of companion dogs during the rainy season exceeded usual limits of bacteria (≤ 2.54 log10 CFU cm-2) on a healthy dog, thus, suggesting that companion dogs harboured in homes situated in Nigeria may be reservoirs of bacteria, especially during rainy season. The mean counts of staphylococci during the rainy season were estimated at 3.09 ± 2.78 log10 CFU cm-2 and 2.77 ± 2.43 log10 CFU cm-2 in Edo and Delta States, respectively. The main Staphylococcus species that were carried on fur of companion dogs included S. pseudintermedius, S. aureus, S. epidermidis, S. simulans and S. saprophyticus. Amongst the staphylococci, expression of methicillin and multidrug resistance was mainly exhibited by S. pseudintermedius and S. aureus, while enterotoxigenicity was mainly expressed by methicillin-resistant S. aureus. Enterotoxigenic S. aureus was carried on the fur of companion dogs during the rainy season at estimated prevalence of 8.57% in both Edo and Delta States, respectively; while PVL-producing S. aureus was estimated at 5.71% and 2.86%, with PVL-producing S. pseudintermedius estimated at 25.71% and 34.29%, respectively. The high prevalence of toxigenic-producing isolates seen on the fur of companion dogs, especially during rainy season, could pose a risk for humans, particularly those that harbour pet dogs at their homes.
Adeola et al (PDF)
Article history: Received: 25 January 2022; Revised: 27 May 2022; Accepted: 4 June 2022; Available online: 30 June 2022
Microbiological Contamination Associated with the Proximity of A Refuse Dumpsite to a River Situated in Okada, Edo State, Nigeria
No full textThis study was performed to evaluate the potential contamination of the Okponha river situated near a dumpsite in Okada, Edo State, Nigeria. Water samples were collected and analyzed for bacteriological and parasitological quality using standard procedures. Isolation and enumeration of bacterial colonies were performed by pour plate technique and the isolated bacteria were identified by standard phenotypic tests. Helminths and protozoa were screened by the direct smear technique. The values of HPC (3.79 ± 0.12 log10 CFU/ml) and TCC (2.20 ± 0.14 log10 CFU/ml) obtained from the river water samples exceeded WHO and NAFDAC recommended limits (≤ 2 log10 CFU/ml and ≤ 1 log10 CFU/ml for HPC and TCC respectively). Bacillus spp., Enterobacter spp., Staphylococcus aureus and Chromatium spp. were the bacteria that were found in the river water samples. Except for the Chromatium spp., the same bacteria present in the river water were also found in the dumpsite soil, thus indicating a potential runoff from the dumpsite. Ascaris lumbricoides and Trichuris trichiura were the main helminth species that were seen in the river water and dumpsite samples, while the main protists that were identified included Entamoeba coli and Giardia lamblia. The high bacterial load seen in the river water is a source of concern because the water is used for a wide range of domestic purposes by inhabitants. Therefore, health authorities should make the public aware of the potential danger in using untreated water as a source of drinking water and also encourage in-house treatment of the raw water
Biorisk Assessment of Medical Diagnostic Laboratories in Nigeria
No full textAbstractBackgroundThe aim of this study was to assess public and private medical diagnostic laboratories in Nigeria for the presence of biosafety equipment, devices, and measures.MethodsA total of 80 diagnostic laboratories in biosafety level 3 were assessed for the presence of biosafety equipment, devices, and compliance rate with biosafety practices. A detailed questionnaire and checklist was used to obtain the relevant information from enlisted laboratories.ResultsThe results showed the presence of an isolated unit for microbiological work, leak-proof working benches, self-closing doors, emergency exits, fire extinguisher(s), autoclaves, and hand washing sinks in 21.3%, 71.3%, 15.0%, 1.3%, 11.3%, 82.5%, and 67.5%, respectively, of all laboratories surveyed. It was observed that public diagnostic laboratories were significantly more likely to have an isolated unit for microbiological work (p = 0.001), hand washing sink (p = 0.003), and an autoclave (p ≤ 0.001) than private ones. Routine use of hand gloves, biosafety cabinet, and a first aid box was observed in 35.0%, 20.0%, and 2.5%, respectively, of all laboratories examined. Written standard operating procedures, biosafety manuals, and biohazard signs on door entrances were observed in 6.3%, 1.3%, and 3.8%, respectively, of all audited laboratories. No biosafety officer(s) or records of previous spills, or injuries and accidents, were observed in all diagnostic laboratories studied.ConclusionIn all laboratories (public and private) surveyed, marked deficiencies were observed in the area of administrative control responsible for implementing biosafety. Increased emphasis on provision of biosafety devices and compliance with standard codes of practices issued by relevant authorities is strongly advocated
A cost-effective scheme developed for studying human malaria caused by Plasmodium falciparum
No full textResearch in human malaria disease has consistently been hindered in developing countries where this disease is endemic, due to the prohibitive cost of constructing and maintaining currently available experimental mouse models. Our goal, therefore, was to develop a cost-effective mouse model that may be used as research tool for studying human malaria disease. Plasmodium falciparum-infected human blood samples were cultured invitro for 92 hours, and invivo malaria infection was induced by intraperitoneally injecting 0.5ml of the Plasmodium falciparum cultures into experimental mice, which were modified by the application of immunosuppressive and humanization protocols in which aspirin (4mg/kg), doxycycline (4mg/kg), and 0.5ml human blood that retained all of its cellular components (erythrocytes, leukocytes, and platelets) were repeatedly injected via the intraperitoneal route. Data obtained showed that the invitro-cultured Plasmodium falciparum significantly retained its infectivity and immunogenicity, since all the 20 mice inoculated exhibited peripheral blood parasitaemia. Quinine chemotherapy using standard antimalarial drug (73mg quinine/kg), however, induced significant suppression of the peripheral blood parasitaemia in the infected mice. Our results suggest that there is a substantial possibility of inducing and eradicating human malaria disease in our mouse model (humanized non-genetically manipulated mouse model) when used as a substitute for the conventional mouse models (humanized genetically manipulated mouse models). Keywords: Synchronized, Invitro, Invivo, Inocula, Immunosuppressed, Parasitaemia, Intraperitoneal, Infectivity
Microbial Diversity in the Sawmill Environment: Implications on the Health of Sawmill Workers and Merchants, Nigeria
No full textThere is an increasingly high suspicion of occupational health diseases amongst workers in sawmill factories. Hence this study aimed to determine the microbial diversity in some sawmill factories in Okada, Edo State, Nigeria to evaluate potential implications of the factory’s processing area on the health of the workers and wood merchants. Bacteria and fungi count in the bioaerosols within the processing area of each factory was performed with the passive air sampling technique. While in the sawdust samples, microbial counts were carried out with the pour plate technique. Identification of the microbes was performed with macroscopic and microscopic examinations as well as standard phenotypic tests. Mean total viable count (TVC) and total fungi count (TFC) of bioaerosols in the air within the processing area of the sawmill factories were found to be greater than 4162.99 CFU/m3 while mean total coliform count (TCC) was reported as 756.28 CFU/m3. Fisher (F) one-way ANOVA test of the TVC and TCC dataset of bioaerosols from the four sawmill factories indicated no significant difference (p = 0.77 and 0.83 for TVC and TFC respectively) in the mean TVC and TFC of the bioaerosols. Bacterial (Micrococcus, Staphylococcus, Bacillus, Klebsiella and Serratia) and fungal (Saccharomyces, Aspergillus, Cladosporium and Penicillium) species were isolated from the bioaerosols and sawdust samples. Results of this study indicated that workers in the sawmill factories and other wood merchants who visit sawmill processing area are most likely exposed to airborne contaminants that may cause occupational diseases such as ophthalmic irritations and dermatitis. Hence it is recommended that sawmill workers and other visitors wear personal protective gadgets in the processing area of the sawmill factories
