- Volume 7, Issue 7, 2025

Introduction. The evaluation of the efficacy of cephalosporin antibiotics sold in Kano, Nigeria, against clinical bacterial isolates is a timely and crucial public health concern. Cephalosporins are among the most widely used antibiotic classes globally due to their broad-spectrum activity and low toxicity. They play a vital role in the empirical treatment of infections involving both Gram-positive and Gram-negative bacteria. However, the increasing misuse and circulation of substandard or falsified antibiotics, especially in informal markets, threatens their therapeutic effectiveness.

Gap statement. In Nigeria, several formal and informal reports of substandard antibiotics and their unregulated sale in open markets, such as Sabon Gari in Kano, raise serious concerns about the quality of drug and their potential contribution to antimicrobial resistance (AMR). Cephalosporins sold in these markets are often sourced and stored under questionable conditions, which increases the risk of reduced potency or inefficacy. At the same time, AMR continues to rise globally, and in low and middle-income countries like Nigeria, poor-quality antibiotics can worsen treatment failure and drive resistance. Sabon Gari market is a major distribution centre for pharmaceuticals, yet research on its impact and extent of substandard drugs is lacking.

Aim. This study aims to assess the pharmaceutical quality of commonly sold cephalosporins purchased from drug distributors in Sabon Gari Market, Kano, by comparing their antimicrobial activity against a panel of clinical bacterial isolates (Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa and Salmonella sp.) with that of standard reference antibiotics.

Methodology. Antimicrobial susceptibility pattern of the test isolates was determined by the disc diffusion method. Fourier transform infrared spectroscopy analysis was used to confirm the functional group of the active ingredients of all the antibiotics tested. Molecular identification of the resistant gene (CTX-M1) was carried out using PCR.

Results. Market survey (n=100) reveals that among drug distributors in Sabon Gari Market, Kano, cephalexin 61% (first generation); cefuroxime 72% (second generation); cefixime 68%, cefpodoxime 79%, ceftriaxone 63%, ceftazidime 70% and cefotaxime 45% (third generation); cefepime 84% (fourth generation) were the most commonly sold cephalosporins, with different brands and company names. These percentages represent the proportion of respondents who reported each antibiotic as one of their most frequently sold products. There is no significant difference between the branded antibiotics (drugs purchased in the market) and standard drugs. Exactly 20% of E. coli and K. pneumoniae were resistant, while 80% of Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas and Salmonella sp. were susceptible. The CTX-M1 resistant gene was identified in E. coli and K. pneumoniae, which further confirms their resistance to cefotaxime and ceftriaxone antibiotics.

Conclusion. Branded cephalosporins sold in Kano were chemically intact and structurally aligned with their respective formulations. No missing or anomalous functional groups were observed that would suggest substandard or counterfeit products, thus fit for human intake.

Background. Nanopore‐based sequencing by Oxford Nanopore Technologies (ONT) offers rapid, cost‐effective and portable sequencing. As an emerging technology, ONT must be evaluated for efficacy and practical application in both high‐ and low‐resource settings. This scoping review (SR) aimed to (1) describe how nanopore technology is used in Africa for surveillance and diagnosis of human infectious diseases, (2) describe how nanopore technology aids in the real-time detection of infectious pathogens in Africa and (3) identify challenges and opportunities for utilizing nanopore technology in Africa to study infectious diseases.

Methods. This SR followed the Joanna Briggs Institute Reviewer’s Manual framework for SRs. English language studies published from 1 January 2008 to 30 April 2024 that used ONT on human specimens collected in Africa and targeted ≥1 microbial agent were included. Searches were performed in Embase, Medline, PubMed, CINAHL and the Cochrane Library. The protocol was publicly available on the Open Science Framework Bastug et al. (Nanopore Sequencing for Infectious Diseases Surveillance and Diagnostics in Africa: a Scoping Review 2024) prior to data collection. Two independent reviewers screened studies using Covidence, and data was extracted using a custom REDCap instrument. Descriptive statistics and data visualization were performed in Microsoft Excel.

Results. One thousand one hundred sixty-two studies were identified and 93 (8%) underwent full-text review. The portable MinION Mk1B was the most common ONT device (65% of studies). Eighty-eight studies analysed specimens from a single African country. Of these, 45% were sequenced in the same country, 7% in a different African country and 11% in a non-African country, while 32% did not specify the location. Specimen types included direct patient specimens (62%) and cultured isolates (35%), or a combination of both. Blood, serum or plasma was most common (35%), followed by naso- or oropharyngeal specimens (27%). Forty-four studies used ONT during an active infectious disease outbreak, 25 of which studied severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Seventy-two studies used ONT for genomic surveillance of infectious pathogens or antibiotic resistance genes, and one study used ONT for a direct clinical application. African-affiliated authors were included as first, middle and last authors in 46% of studies, and 15% were published by entirely African-affiliated teams. Ten studies published information on workflow timeline, and five studies published the per-specimen cost.

Conclusions. ONT can enable timely and affordable sequencing in African countries as demonstrated through a small number of studies that accomplished these goals individually. Most studies used ONT for genomic surveillance of pathogens or antimicrobial resistance genes, while only one study used ONT directly for a real-time clinical application. A small number of studies described a short interval between specimen collection and sequence result, supporting that clinical applications are possible. There is a need for improved reporting of ONT methodology including pipeline timelines, cost, use of barcoding, flow cell models and the use of negative controls. Publications that provide these details will enhance reproducibility and support the development of new studies using ONT for the diagnosis and surveillance of infectious diseases in low-resource settings.

Staphylococcus argenteus (SARG) was discovered in 2009 as part of the Staphylococcus aureus (SAUR) complex and has been documented from various locations worldwide. In this article, we describe the genomic features of five strains of SARG found in Christchurch, New Zealand. Isolates were first detected in 2019 using MALDI-TOF identification, and their identities were confirmed using whole-genome sequencing. Genomic features, including antimicrobial resistance markers and virulence factors, were compared with other SARG sequences in the NCBI GenBank and well-characterized features in SAUR. Four isolates belonged to ST2250 and one isolate to ST2793. Phylogenetic analysis based on core genome analysis revealed that all five isolates were phylogenetically distinct, with four isolates clustering in the ST2250 clade. Three isolates contained staphylococcal cassette chromosome mec (SCCmec) type IV 2Bc, harbouring the mecA gene conferring resistance to beta-lactam antibiotics. All five strains shared many of the virulence genes found in the global SARG and SAUR isolates; however, no TSST-1 or PVL pathogenic genes were detected. This publication contributes additional data on global occurrences and genomic features of SARG.

Shiga toxin-producing Escherichia coli (STEC) poses a significant public health risk due to its zoonotic potential and association with foodborne outbreaks. This study investigates the presence of STEC in faecal samples collected from sheep, focusing on bacteriological methods for isolation and preliminary characterization. Growth on selective agar showed that 90 of 140 faecal samples were positive for STEC. The total average prevalence was 64.3% (95% CI 56.1–71.7%). The highest prevalence was 71.4% (54.9–83.7%), recorded in summertime, while the lowest was 51.4% (35.6–67%) in the autumn. Selected isolates were found to be resistant to commonly used antibiotics, with isolates expressing a resistant phenotype to two, three or more of the tested antibiotics. Based on the Biocheck.UGent system for risk-based assessment of farm biosecurity, the total, internal and exterior average farm biosecurity scores were substantially lower than the world average.

Consequences of Shiga toxin-producing Escherichia coli (STEC) infection can range in severity from asymptomatic infection to haemolytic uraemic syndrome, renal failure and death. Groundwater-derived drinking water is an important route for STEC transmission. Detection of STEC in water is crucial for timely response and public health interventions; however, currently used culture-based methods are time-consuming and laborious. Therefore, there is a need for rapid methods that maintain high sensitivity and specificity [ 1 ]. We describe a novel, sensitive, enrichment-free water filtration method using a convenient sample volume (100 ml) to detect DNA markers of STEC serogroups and virulence factors within 6 h. Quantitative real-time PCR (qPCR) was used to detect and quantify the most common STEC infection-associated serogroups globally, O157 and O26. Real-time PCR was used to detect genetic determinants of STEC virulence (stx1, stx2 and eae genes) and specific marker genes for the clinically relevant serogroups O111, O103, O145 and O104. Results showed that the novel method can detect as low as 5 c.f.u. ml−1 of STEC in water. The limit of detection for O157 and O26 qPCR assays was two and six copies, respectively. Groundwater and surface water samples (n=28) were collected and processed using the novel method. STEC O157 and O26 serogroups were detected in 23 out of 28 (82.1%) samples (mean 5.2×104 copies/reaction) and 19 out of 28 (67.9%) samples (mean 7.83×104 copies/reaction), respectively. Shiga toxin genes stx1 or stx2 were detected in 15 out of 28 (53.6%) and 9 out of 28 (32.1%) samples, respectively. The virulence factor intimin gene eae was detected in 24 out of 28 (85.7%) samples. STEC serogroups O111, O103, O145 and O104 were detected in 15 out of 28 (53.6%), 10 out of 28 (35.7%), 11 out of 28 (39.3%) and 15 out of 28 (53.6%) samples, respectively. This novel method reproducibly detects low copies of STEC in low-volume fresh water and has the potential to be used for the detection and quantification of waterborne bacterial pathogens.

Diarrhoeal diseases remain a significant global health challenge, particularly in developing regions such as Africa, Asia and Latin America, where they are a leading cause of child mortality. Contaminated food, including raw or undercooked vegetables, is a major transmission route for diarrhoeal pathogens such as norovirus, Campylobacter, non-typhoid Salmonella and pathogenic Escherichia coli. This study aimed to assess the prevalence of enterotoxigenic E. coli (ETEC), a key diarrhoeal pathogen, in fresh produce and prepared salads in Mexico City. A total of 128 samples, including prepared salads (lettuce, carrots and tomatoes) and unprocessed coriander and lettuce, were analysed over 2 years using protocols from the Bacteriological Analytical Manual and the Official Mexican Standard (NOM) SSA 210. Genotyping was performed to detect ETEC-specific virulence genes encoding heat-stable and heat-labile enterotoxins (st and lt), respectively. ETEC was identified in 9.9% of the total samples, representing 51.56% of the confirmed E. coli isolates. Contamination rates varied by food type, with coriander showing the highest prevalence (78.78%), followed by lettuce (9.09%) and prepared salads from La Vicentina Market (9.09%) and La Purísima Market (3.03%). Genotyping revealed that 12.12% of the ETEC-positive samples carried both st and lt genes, while 33.3 and 54.6% carried only the lt or st gene, respectively. In lettuce samples, 9.09% were positive for ETEC, with 3.03% carrying the lt gene, 3.03% the st gene and 3.03% both genes. Similarly, in coriander, 21.21% were positive for the lt gene, 51.51% for the st gene and 6.06% for both genes. These findings highlight the widespread presence of ETEC in fresh produce sold in Mexico City, posing a significant public health risk, particularly given the increasing consumption of raw vegetables. The study provides the first reported data on ETEC contamination ratios in Mexico City, emphasizing the urgent need for improved food safety measures, including better hygiene practices during production, handling and preparation of fresh produce. This research underscores the importance of ongoing surveillance and preventive strategies to mitigate the risk of foodborne diarrhoeal diseases in urban populations.

Tuberculosis is a major scourge, posing a serious public health problem in countries where it is endemic. Osteoarticular involvement accounts for 3–5% of all tuberculosis cases and 10–15% of extrapulmonary tuberculosis cases. We report a case of tibial osteitis caused by Mycobacterium tuberculosis in a 52-year-old female patient who presented to the trauma department at the Mohammed V Military Teaching Hospital with a painful swelling of the lower part of her left leg. Standard X-rays and computed tomography scans revealed bone involvement, specifically in the tibia. Additional investigations revealed pulmonary consolidation and splenic nodules. Microscopy (Ziehl–Neelsen staining), GeneXpert MTB/RIF and histopathological examination all returned positive results for M. tuberculosis. In an endemic context, any persistent and atypical bone lesion should raise suspicion of osteoarticular tuberculosis to enable rapid diagnosis and appropriate therapeutic management. In the absence of malignant tumours and other differential diagnoses, the diagnosis of skeletal tuberculosis must be considered, even in the absence of specific clinical signs.

Psoas abscess is a rare infection historically associated with tuberculosis (TB), although non-tuberculous bacterial causes, particularly Staphylococcus aureus, have become increasingly common. This type of abscess can be either primary or secondary, and its diagnosis remains challenging due to the non-specific nature of clinical signs. Imaging and microbiological analyses are essential for establishing the diagnosis. We report the case of a 22-year-old patient with no significant medical history, who presented with persistent mechanical low back pain for 18 months. Initial computed tomography revealed a non-compressive disc protrusion, leading to treatment with non-steroidal anti-inflammatory drugs, without improvement. Further investigations revealed an extrapulmonary spinal localization of TB in an immunocompetent patient, with bilateral psoas abscesses caused by Mycobacterium tuberculosis, confirmed by the Ziehl–Neelsen staining, auramine staining, culture on Löwenstein–Jensen medium and GeneXpert PCR. Anti-TB treatment was initiated, resulting in favourable clinical evolution.