Co-existence of extended-spectrum ß-lactamases blaCTX-M-9 and blaCTX-M-15 genes in Salmonella species isolated from febrile and diarrhoeagenic patients in Lagos, Nigeria: a cross-sectional study.

BACKGROUND: Resistance to different antimicrobial classes by Salmonella species has generated a global public health concern. The spread of extended-spectrum ß-lactamases (ESBLs) blaCTX gene variants is also increasing. This study aimed to investigate the antibiotic resistance and the carriage of blaCTX-M-9 and blaCTX-M-15 as well as the quinolone resistance gene (qnrB19) among Salmonella species from hospitalised patients in Lagos, Nigeria. METHODS: In this cross-sectional study from April 2021 to August 2021, a total of 508 samples were collected from hospitalised patients. The samples were subjected to standard microbiological investigation. All the isolates were identified using API 20E kits and real-time polymerase chain reaction (RT-PCR). The in vitro antibiotic susceptibility testing (AST) was investigated using the disk diffusion method. Detection of antibiotic resistance and virulence gene makers was conducted using RT-PCR. RESULTS: In total, 24 Salmonella species were identified. All the isolates were non-typhoidal Salmonella isolates. None of the isolates screened was S. Typhi and S. Paratyphi. Most of the isolates were susceptible to imipenem, ciprofloxacin, ofloxacin and gentamycin, while a high level of resistance to all cephalosporins, penicillin, and some carbapenems was observed. In total, 79.2% (19/24) of the Salmonella isolates harboured the blaCTX-M variant including 54.2% (13/24) blaCTX-M-9 and 12.5% (3/24) blaCTX-M-15, while co-habitation of blaCTX-M-9 and blaCTX-M-15 was observed in 12.5% (3/24) of the isolates, respectively. None of the isolates harboured quinolone-resistant qnrB19 gene and virulence gene stn. However, invA gene was present in 66.7% (16/24) of all isolates. CONCLUSIONS: This study is considered the first report of blaCTX-M-9 and blaCTX-M-15 variants in Salmonella species in Nigeria. The continued existence of cefotaximase (CTX-M)-producing Salmonella within our environment calls for the prudent use of cephalosporins.

Human and Animal Brucellosis in Nigeria: A Systemic Review and Meta-Analysis in the Last Twenty-One Years (2001-2021).

The global burden of human and animal brucellosis remains enormous. The disease, which is endemic in Nigeria, lacks appropriate attention and national data. This review estimated the burden and distribution of human and animal brucellosis in Nigeria in the last twenty years (2001-2021). Publications reporting the detection of brucellosis in Nigeria were sorted from different search engines, including PubMed, ResearchGate, Scopus, and Google Scholar, to generate data on its prevalence, spatial distribution, and predisposing factors. The results of the national seroprevalence of human and animal brucellosis as revealed in this study were 17.6% (554/3144) and 13.3% (8547/64,435), respectively. Specifically, 15.8% (7178/45,363) seroprevalence of brucellosis was recorded in northern Nigeria as against 8.7% (1902/21,740) seroprevalence in the southern part. It also indicated that 78.7% of the detected brucellae were un-typed. The Brucella species detected were B. abortus (15.2%), B. melitensis (4%), B. suis (1.8%), and B. canis (0.4%). This study revealed that brucellosis is endemic in Nigeria. Culture and molecular methods for detecting brucellosis and reports on antimicrobial susceptibility testing remain a conjecture. This review will help researchers redirect their research focus and serve as a guide for policymakers on measures for managing brucellosis in Nigeria.

Associated risk factors and pulsed field gel electrophoresis of nasal isolates of Staphylococcus aureus from medical students in a tertiary hospital in Lagos, Nigeria.

Staphylococcus aureus infections are growing problems worldwide with important implications in hospitals. The organism is normally present in the nasal vestibule of about 35% of apparently healthy individuals and its carriage varies between different ethnic and age groups. Staphylococcal nasal carriage among health workers is particularly important to establish new clones and track origin of infections during outbreak situations. To determine the carriage rate and compare the pulsed field gel patterns of the strains, nasal swabs were collected from 185 medical students in a teaching hospital in Lagos, Nigeria. Isolates of S. aureus were tested for heamolysin production, methicillin sensitivity and Pulsed Field Gel Electrophoresis (PFGE) was performed. The results showed S.aureus nasal carrier rate of 14% with significant rate among males compared to females. All the isolates produced heamolysin. Antibiotic susceptibility pattern revealed that majority of the isolates was susceptible. Five strains (19%) harboured resistant determinants to penicillin and tetracycline. None of the strains was resistant to methicillin. 44% of the isolates typed by PFGE had type B, the most predominant pulsotype. PFGE A clone exhibited a single resistance phenotype suggesting a strong clonal relationship that could punctual an outbreak in the hospital. The results speculate that nasal carriage among medical personnel could be a function of various risk factors. Personal hygiene and behaviour may however be the means to reducing colonization and spread of S.aureus in our hospitals.

Associated risk factors and pulsed field gel electrophoresis of nasal isolates of Staphylococcus aureus from medical students in a tertiary hospital in Lagos, Nigeria

Staphylococcus aureus infections are growing problems worldwide with important implications in hospitals. The organism is normally present in the nasal vestibule of about 35 percent of apparently healthy individuals and its carriage varies between different ethnic and age groups. Staphylococcal nasal carriage among health workers is particularly important to establish new clones and track origin of infections during outbreak situations. To determine the carriage rate and compare the pulsed field gel patterns of the strains, nasal swabs were collected from 185 medical students in a teaching hospital in Lagos, Nigeria. Isolates of S. aureus were tested for heamolysin production, methicillin sensitivity and Pulsed Field Gel Electrophoresis (PFGE) was performed. The results showed S.aureus nasal carrier rate of 14 percent with significant rate among males compared to females. All the isolates produced heamolysin. Antibiotic susceptibility pattern revealed that majority of the isolates was susceptible. Five strains (19 percent) harboured resistant determinants to penicillin and tetracycline. None of the strains was resistant to methicillin. 44 percent of the isolates typed by PFGE had type B, the most predominant pulsotype. PFGE A clone exhibited a single resistance phenotype suggesting a strong clonal relationship that could punctual an outbreak in the hospital. The results speculate that nasal carriage among medical personnel could be a function of various risk factors. Personal hygiene and behaviour may however be the means to reducing colonization and spread of S.aureus in our hospitals.

Human campylobacteriosis in developing countries.

Campylobacteriosis is a collective description for infectious diseases caused by members of the bacterial genus Campylobacter. The only form of campylobacteriosis of major public health importance is Campylobacter enteritis due to C. jejuni and C. coli. Research and control efforts on the disease have been conducted more often in developed countries than developing countries. However, because of the increasing incidence, expanding spectrum of infections, potential of HIV-related deaths due to Campylobacter, and the availability of the complete genome sequence of C. jejuni NCTC 11168, interest in campylobacteriosis research and control in developing countries is growing. We present the distinguishing epidemiologic and clinical features of Campylobacter enteritis in developing countries relative to developed countries. National surveillance programs and international collaborations are needed to address the substantial gaps in the knowledge about the epidemiology of campylobacteriosis in developing countries.