Salmonella infections remain a global challenge. The culture method is the gold standard for the detection of genus Salmonella. Application of Polymerase Chain Reaction (PCR) has become an effective tool for the detection of virulence and antimicrobial resistance genes. This study investigated the prevalence of Salmonella by culture and detection of invA gene and blaCTX-M and blaCTX-M-3 gene markers by PCR. A total of 612 blood samples were collected from hospitalized febrile patients between March 2020 and April 2021. The samples were cultured, isolates identified by standard method with Analytical Profile Index (API 20-E) kits and were subjected to in-vitro antimicrobial susceptibility test (AST) using disk diffusion method. Extended-spectrum beta-lactamase (ESBL) detection was carried out by double-disc synergy test. Detection of invA gene and antibiotic-resistant genes makers was done by qPCR. A total of 24 Salmonella isolates were identified given a prevalence of 3.9% Salmonella-associated bacteraemia. Children within 1-10 years with persistent pyrexia of unknown origin (PUO) accounted for 50% of the Salmonella isolated with a mean age of 5.299 years. Specifically, 75% (18/24) Salmonella isolates and their corresponding samples of positive Salmonella culture were positive for the invA gene. The AST results indicated 100% Salmonella isolates developed resistance to ceftazidime, cefotaxime , augmentin, ampicillin, ertapenem, and doripenem. None of drug resistant-Salmonella isolates expressed ESBL enzyme phenotypically. Seven resistance patterns were observed, and the pattern CAZ-CTX-OFL-AUG-NIT-AMP-ETR-DOR was the most encountered pattern. Twelve (50%) Salmonella isolates harbored the blaCTX-M and blaCTX-M-3 genes and were mostly from children. The study has added to the growing knowledge on the suitability of the invA gene primer set as a PCR target for the detection of Salmonella. It also revealed a paradigm shift in the occurrence of invasive Salmonella harboring blaCTX-M and blaCTX-M-3 genes in PUO cases. There is a need for judicious use of cephalosporin and carbapenem antibiotics to preserve their efficacies.

Introduction: Salmonella enterica Serovars remains one of the leading pathogens that cause diarrhoea and bloodstream infections in developing countries. The emergence of multidrug resistant (MDR) Salmonella has become a serious problem globally. This study investigated the antibiotic resistance and plasmid profiles of Salmonella isolates from different sources. Methods: Seventy-three samples comprised of clinical (30), hand swab (15), food (10) and water (18) were analyzed bacteriologically. Salmonella isolates were identified and characterized by standard procedures. Isolates were subjected to antimicrobial susceptibility testing and were further screened for plasmid DNA by standard methods. Results: A total of 27 Salmonella isolates made up of 5 (18.5%) S. typhi, 6 (22.2%) S. enteritidis, 9 (33.3) S. typhimurium, 5 (18.5%) S. cholerasuis, and 1 (3.7%) each of S. arizonae and S. vichow were obtained in this study. All the isolates developed resistance to three or more antibiotics evaluated. Four distinct resistance profiles: TetAmpCol, TetAmpColCot, Te-tAmpColCip and TetAmpColCotCip were recorded with 63% of the isolates exhibiting resistance profile TetAmpColCot. Specifically 23 of 27 (85.2%) of the isolates harboured plasmid DNA comprised of 12 distinct plasmid profiles of different sizes ranging from 3.2 kb to 30.2 kb. Salmonella isolates of the same species from different sources differed in plasmid profile. Plasmid profile was found to show good discriminatory capability compared to antibiotics resistance profile. Conclusion: This study revealed that both resistance antibiogram and plasmid profile are still viable epidemiological tools for tracing the source of Salmonella isolates. A need for prudent use of antibiotics is suggested.

Multidrug drug-resistant (MDR)-Acinetobacter baumannii (A. baumannii) is one of the most feared nosocomial bacterial agents worldwide, and the World Health Organization classified carbapenem-resistant strains as a priority ”1” critical pathogen. In Nigeria, the paucity of information on this pathogen makes it difficult to estimate its potential impact on public health and veterinary medicine. This systemic review was done to prepare an impact assessment for One Health based on the occurrence of A. baumannii in different environments and the antimicrobial resistance. A detailed search of articles on A. baumannii in Nigeria was conducted using search strings in the following databases: PubMed, Scopus, Google search engine, and Google scholars. This study revealed that 14 out of the 36 states in Nigeria reported A. baumannii. Specifically, 19/24 articles described isolates from clinical settings, 4/24 from the environment, and 1/24 from animal sources. A. baumannii occurrence of 9.15% (503/5496) was recorded from 8.4% (418/4950), 16.06% (80/498), and 10.42% (5/48) of samples of clinical, environmental, and animal origin by culture, respectively. The most common antibiotics to which A. baumannii was resistant were chloramphenicol, ampicillin-sulbactam, amoxicillin, amoxicillin-clavulanate, cefuroxime, ceftazidime, ceftriaxone, gentamycin, and tetracycline. Seventeen resistance determinants were described for A. baumannii isolates originating mostly from clinical sources with blaOXA-51 and blaOXA-23 gene makers frequently reported. This study demonstrates the lack of data on A. baumannii from animals. Clinical MDR- A. baumannii isolates, particularly in Intensive Care Units (ICUs), are a severe public health concern in Nigeria. Thus, findings from this review will form a baseline for future surveillance research.

Influenza D virus (IDV) was first reported in pigs in the USA, and since then the virus has become a public health issue. In Nigeria, no work has been done on IDV despite the manifestation of influenza-like illness in cattle. This study aimed at molecular surveillance of IDV in cattle in Lagos. Prospective epidemiological investigation was initiated in a large commercial farm market where animals in open pens are reared, sold, and butchered under poor hygienic conditions without adequate biosecurity measures. A total of 80 nasopharyngeal swabs were collected between October and November 2021. The samples were extracted using an RNA purification kit (NIMR). RNA extracts were amplified following a two-step PCR using FIREScript RT cDNA synthesis kit (Solis Biodyne, Estonia), followed by PCR OneTaq Quick-load 2x master-mix (NEB, UK) in a Rotor-Gene thermocycler (Qiagen, Germany). Amplicons were detected using a 1.5% Gel electrophoresis. IDV was detected in 26/80 (32.5%) cattle. Sick animals showed 65% (17/26) almost double burden of IDV higher than 34.6% (9/26) in a healthy population, including 88.2% (15/17) Cattle with diarrhoea and 11.8% (2/17) with nausea having IDV. Bull recorded more than twice, 18/26 (69.2%) incidence by gender compared to Cow. Age prevalence showed 62.23% (18/26) highest detection in cattle of 4 years old, followed by 23.07% (6/26) in 5 years old, while the lowest 7.69% (2/26) was recorded in 3 years old. This study showed the first molecular detection of IDV in Nigeria and West Africa sub-region to the best of our knowledge. It underscores the need for continuous surveillance of IDV at the animal-human interface.

Petroleum-based products are the major source of energy for industry and daily life. Leaks and accidental spills occur regularly during the exploration, production, refining, transport, and storage of petroleum and petroleum products. Crude oil-impacted tropical soil and natural water samples (0 -30cm depth) were obtained from the Niger Delta, Nigeria. A total of twenty seven bacterial species of relevance in bioremediation were isolated and characterized using standard and conventional methods. The predominant species belong to the genera Pseudomonas and Proteus. The ability of Pseudomonas aeruginosa, Pseudomonas stutzeri, Proteus mirabilis, Serratia marcescens and Bacillus subtilis to degrade diesel oil was studied. The results showed maximal increase in optical densities and total viable counts, however, with decrease in pH of the culture media after 8 -day incubation period. Typical generation times varied between 0.89 and 4.0d for Pseudomonas aeruginosa, 0.85 and 0.32d for Pseudomonas stutzeri, 0.8 and 3.9d for Proteus mirabilis. All the isolates utilized petroleum hydrocarbon as sole carbon and energy sources for growth on Minimal Salt Medium (MSM) supplemented with (0.2%) diesel oil. The isolates were tested against 7 different antibiotics and were found to be resistant to 5 antibiotics. Consequently, Twenty four isolates were randomly selected for plasmid DNA isolation. The presence of plasmid DNA was confirmed in 22 isolates where the molecular weight size ranged between 7 -23.1kb. Although, Pseudomonas aeruginosa, Proteus mirabilis and Bacillus subtilis had low specific growth rate on Diesel, they were the best choice for bioremediation since they had the highest mean generation time respectively. The knowledge of the potentials of these isolates to degrade hydrocarbons will increase the possibilities of developing novel strains and strategies for removing hydrocarbon pollutants from the natural environment.