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Background: Mobilized colistin resistance (MCR) is a public health problem resulting in limited therapeutic options. Objective: This study aims to phenotypically detect mobilized colistin resistance (MCR)-mediated resistance in a setting where colistin is not used. Method: The combined disk test (CDT) technique and minimum inhibitory concentration (MIC) were used to screen a total of 238 isolates for the existence of MCR producers. Results: Of the 238 isolates, 47 (19.75%) were CDT positive, and 37 out of the 47 had MIC >2mg/L and were referred to as MCR producers. Age, gender, type of specimen and the wards/clinics the isolates were recovered from did not significantly affect the prevalence of MCR producers (p>0.05). Type of isolate significantly (p=0.0184) affected the prevalence of MCR producers. Conclusion: This study underscores a high prevalence [15.55% (37/238)] of phenotypically detected MCR-mediated colistin resistance in a resource-poor setting were colistin is not used.

The rise in prevalence of methicillin resistant staphylococci implicated in clinical infections worldwide continues to elicit interest in nasal colonization rates for these resistant strains. This study was aimed at determining the prevalence of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative staphylococci (MRCoNS) among apparently healthy students of a tertiary institution in Benin City, Nigeria. A total of 350 students were recruited for the study and nasal swabs were collected alongside demographic data. These swabs were processed microbiologically using standard techniques to recover staphylococci. Antimicrobial susceptibility and methicillin-resistance was determined using a phenotypic method (cefoxitin resistance). A total of 148 (42.3%) of 350 students were culture positive for S. aureus, while 72 (20.6%) were positive for CoNS. Students from Faculty of Dentistry showed the highest prevalence of nasal MRSA (40.0%) and MRCoNS (20.0%). Ofloxacin and gentamicin were the most active antibacterial agents against MRSA with 89.1% and 87.3% respectively been susceptible, while gentamicin was the most active antibiotic against MRCoNS (75.0%). Nasal colonization by MRSA and MRCoNS was unaffected by area of residence and gender (P > 0.05). The nasal carriage rate of MRSA and MRCoNS was 37.2% and 33.3% respectively. The study recommends periodic review of nasal colonization rates among apparently healthy subjects. Regulated use of antimicrobial agents is imperative in order to stem the tide of resistance.

Background: Serine and zinc type carbapenemases are distributed in many genera of bacteria and are typically associated with specific regions or countries. Objectives: This study phenotypically determined the prevalence of serine and zinc-type carbapenemases among Gram-negative bacilli recovered from clinical specimens in Benin, Nigeria. Materials and Methods: Totally, 158 consecutive non-duplicate bacterial isolates (gram-negative bacilli) recovered from clinical samples were screened for serine and zinc-type carbapenemases using the simplified carbapenemase inactivation (sCIM) and ethylenediaminetetraacetic acid -double-disc synergy test methods. Results: The isolates recovered from clinical specimens included 126 Enterobacteriaceae (79.7%), 7 Acinetobacter spp (3.7%), and 28oxidase positive gram negative bacilli (17.7%). Twenty-eight isolates (17.7%) out of the 158 tested samples were carbapenemase positive. There was no significant difference in the prevalence of serine- and zinc-type carbapenemases (P=0.0748). However, the prevalence of zinc-type carbapenemase was significantly higher in Pseudomonas aeruginosa compared with other isolates (P=0.0028) while that of serinetype carbapenemase was not affected by the type of clinical isolates (P=0.7216). Finally, the prevalence of both serine- and zinc-type carbapenemases were not affected (P>0.05) by clinical specimens and the source of isolates (in-patient vs. out-patient) respectively. Conclusion: In general, the prevalence of zinc-type (12%) carbapenemases was insignificantly higher than that of serine-type (5.7%) carbapenemases. The measures to reduce infections caused by carbapenemase-producing organisms (CPOs) are advocated accordingly.

The 2019 Coronavirus pandemic which was initially referred to as 2019-nCoV, was first identified in Wuhan, China. Early response from the Chinese government included quarantine of infected persons, isolation and total lockdown of Wuhan province to prevent further spread. With the spread of the disease across national borders and declaration of the disease as a global pandemic, there has been a robust response by the international community to contain this deadly virus and prevent its further spread worldwide. Africa is not left out of this rampaging pandemic with documented cases in over 40 countries and still rising. Although extensive studies have been carried out on the novel SARS-CoV-2 on its pathogenesis, mode of infection and virulence but much is still unknown. However, potentially infectious samples are received routinely in the medical laboratory for analysis. This technical note reviews good laboratory practice (GLP) and processes across the different specialities of Medical Laboratory practice that should minimize the risk of infection to laboratory staff especially in resource-limited settings.

Background: Multidrug resistant bacteria continue to be a bane in the treatment of clinical infections in Nigeria. Knowledge of trends in resistance mechanisms is vital in determining available therapeutic options. Objective: This study was aimed at determining the prevalence, distribution and antimicrobial susceptibility of extended spectrum β-lactamase (ESBL), AmpC β-lactamase and metallo-β-lactamase (MBL)-producing gram negative bacteria (GNB) recovered from clinical specimens in a tertiary hospital in Southern Nigeria. Materials and Methods: A total of 309 consecutive non-repetitive clinical bacterial isolates were recovered from various clinical specimens. The presence of ESBL, AmpC β-lactamase and MBL as well as the susceptibility profiles were determined using standard microbiological techniques. Results: ESBL was the most prevalent (P < 0.0001) of the 3 enzymes detected in this study. Bacterial isolates recovered from inpatients had a higher likelihood of producing ESBL than those recovered from out-patients (odds ratio [OR] = 2.225, 95% CI = 1.375, 3.599; P = 0.0015). The highest prevalence of ESBL, AmpC and MBL enzyme was observed for Providencia species, Pseudomonas aeruginosa and Citrobacter species respectively. β-Lactamase positive isolates showed poor activity against cephalosporin, amoxicillin-clavulanate, gentamicin and the fluoroquinolones. Isolates that produced any of the three β-lactamase enzymes showed more resistance to antibacterial drugs than β-lactamase negative bacterial isolates. Conclusion: A prevalence of 41.7%, 15.2% and 28.5% was observed for ESBL, AmpC β-lactamase and MBL respectively in this study. Isolates that produced any of the enzymes were more resistant to antibacterial agents. Prudence in antibiotic use is strongly advocated.

This study was carried out to determine the prevalence of extended spectrum beta-lactamase (ESBL) among Gram negative bacteria isolated from cattle feces in Benin City, Nigeria. A total of 250 Gram negative bacteria isolates were recovered from cattle feces and were processed microbiologically using standard techniques. Emergent colonies were identified and antibacterial susceptibility tests were determined using Kirby-Bauer disk diffusion method. All bacterial isolates were screened for the presence of ESBL using the double-disc synergy method. A total of 37 (14.8%) isolates were positive for ESBL, with 33 (13.2%) indicated by ceftazidime, while only 4 (1.6%) were indicated by both ceftazidime and cefotaxime (P < 0.0001). Of the Gram negative bacterial isolates recovered, Salmonella species was the most prevalent ESBL-producer with 55.0% prevalence (P = 0.0092), while no isolate of Pseudomonas aeruginosa produced ESBL. ESBL-positive isolates showed poor susceptibility to the tested antibacterial agents in comparison with non-ESBL-producers and imipenem was the most active antibiotic. The prevalence of ESBL among Gram negative bacilli recovered from cattle feces was 14.8%. The study advises prudent use of antibiotics in the treatment of cattle and harps on improved hygiene in managing cattle, as they are potential reservoirs of ESBL-producing organisms.

The emergence of HIV has reawakened the tuberculosis (TB) scourge and infected patients are prone to opportunistic infections, this study was carried out to determine the HIV status and etiologic agents of Lower respiratory tract infections (LRTI) among tuberculosis suspected patients in Benin City, Nigeria. The study was cross sectional. A total of 276 patients attending tuberculosis clinic were recruited. Questionnaires were filled for each patient. Blood and sputum specimens were collected in plain and sterile containers respectively and transported immediately to the laboratory. Blood samples were screened for the presence of HIV antibodies. The sputum specimens were then cultured following standard microbiological procedure, and thereafter processed using the GeneXpert MTB/RIF assay. Emergent bacterial colonies were identified and susceptibility testing was carried out following standard microbiological techniques. A total of 118 (42.8%) non-mycobacterial bacterial agents were recovered from the patients. Patients were more likely to be culture positive for LRTI in comparison with TB infection (p < 0.0001). There was no association between TB and HIV status (OR = 0.6161, 95%CI = 0.226, 1.648, p = 0.4474). HIV positive patients were more likely to be culture positive for bacterial agents and Klebsiella pneumoniae was more likely to be recovered (p = 0.0338). The fluoroquinolones, gentamicin and ceftriaxone-sulbactam were the most active antibacterial agents against bacterial isolates. The prevalence of LRTI in this study was 52.2%. The study draws attention on the need for physicians to request for bacteriological culture (non-mycobacterial) alongside the TB diagnostic algorithm in suspected TB cases. Keywords: Tuberculosis, HIV, opportunistic infections, patients, bacteria

TheThis study sought to investigate the occurrence and distribution ofNinety one (91) clinical isolates comprisingThis study draws attention on the increase in the prevalence of

Background: The staphylococci have increasingly been associated with infections worldwide and anti-microbial resistance has made these versatile pathogens more recalcitrant in the hospital setting. Objectives : This study sought to investigate the occurrence and distribution of Staphylococcus species as well as determine the prevalence of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative staphylococci (MRCoNS) among clinical samples from University of Benin Teaching Hospital (UBTH) in Benin City. Methods: Ninety one (91) clinical isolates comprising S. aureus and Coagulase Negative staphylococci (CoNS) were recovered from routine clinical specimens and anti-microbial susceptibility tests were carried out. Polymerase Chain Reaction (PCR) was thereafter carried out on these isolates to detect mecA gene. Results : Staphylococcus species had its highest prevalence from infected wounds of patients (28.8%) while urine samples showed the least (5.4%). The highest level of resistance was to ceftazidime (S. aureus - 68%, CoNS - 75.6%) while the least resistance was observed for meropenem (S. aureus- 26%, CoNS- 46.3%). Using phenotypic method (with 1μg oxacillin antibiotic disc), the distribution of MRSA and MRCoNS was 44.0% and 46.3% respectively. PCR analysis showed that 38.0% of S. aureus and 41.5% of the CoNS had mecA gene respectively; wound swabs showed the highest prevalence with 30.5% of staphylococcal isolates being mecA gene positive. There was also no significant association between the Staphylococcal isolates and their isolation rate, isolation site and mecA gene distribution (p > 0.05). Conclusion : This study draws attention on the increase in the prevalence of mecA gene (39.6%) and an increase in multidrug resistant staphylococci when compared to previous studies in our country; it recommends laboratory guidance and periodic review to stem the tide of resistance. Keywords: Staphylococcus aureus (S. aureus ), coagulase-negative staphylococci (CoNS), mecA gene, methicillin-resistance