Clinical Report: Trends in Antimicrobial Resistance in The Gambia (2019-2024)
Background
Invasive bacterial pathogens remain an important cause of morbidity and mortality worldwide, particularly in low- and middle-income countries. In The Gambia, the introduction of Haemophilus influenzae type b and pneumococcal conjugate vaccines has altered the epidemiological landscape by reducing infections caused by vaccine-targeted pathogens. Antimicrobial resistance also remains a substantial concern. Previous estimates cited by the authors attributed 329 deaths directly to antimicrobial resistance and associated 1,610 deaths with antimicrobial resistance in The Gambia in 2021. Children younger than 5 years had the greatest burden, with 565 antimicrobial resistance-associated deaths and a mortality rate of 971 per 100,000.
Data Highlights
The study reviewed 7,496 clinical specimens processed at the Clinical Microbiology Laboratory of the Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine from January 2019 through December 2024. After noninvasive specimens, duplicate isolates, contaminated samples, and incomplete records were excluded, 423 invasive isolates were included in the analysis.
Key Findings
Staphylococcus aureus was the most common invasive bacterial pathogen, accounting for 32.9% of isolates, followed by Escherichia coli at 17.5%, Streptococcus pyogenes at 9.9%, Streptococcus pneumoniae at 9.7%, and Klebsiella pneumoniae at 8.5%.
S. aureus showed 92.0% resistance to penicillin, and methicillin-resistant S. aureus accounted for 10.0% of isolates.
E. coli showed 92.0% resistance to ampicillin and 44.2% resistance to ciprofloxacin, while S. pneumoniae showed 97.0% resistance to cotrimoxazole.
S. pneumoniae was more common during the dry season, whereas K. pneumoniae was more common during the wet season.
Whole-genome sequencing of 40 S. aureus isolates showed mecA-positive isolates distributed across multiple phylogenetic clades, supporting polyclonal rather than single-strain emergence of methicillin-resistant S. aureus.
Clinical Implications
The findings support the use of institution-level antimicrobial resistance surveillance, genomics, and updated antibiograms to inform empirical treatment and antimicrobial stewardship. Because the study was conducted at a single research-affiliated diagnostic laboratory, the findings should inform local prescribing and stewardship at the study institution rather than be generalized to national invasive bacterial pathogen epidemiology in The Gambia.
Conclusion
The study provides updated institution-level evidence on invasive bacterial pathogen epidemiology and antimicrobial resistance trends at the Medical Research Council Unit The Gambia. The authors recommend coordinated multisite national surveillance to develop a representative picture of antimicrobial resistance epidemiology across Gambian health care settings and support development of national empirical treatment guidance.
Related Resources & Content
Epidemiology and antimicrobial resistance trends of invasive bacterial pathogens in the Gambia: a retrospective analysis, 2019-2024 — Abdulrahman Yakubu Mohammed, Mustapha Dibbasey, Buntung Ceesay, Morrow Minteh, Solomon E. Umukoro, Ousman Secka, and Abdoulie Bojang — International Journal of Infectious Diseases — Publication year: 2026; accepted September 14, 2026.
Community-acquired invasive bacterial disease in Urban Gambia, 2005-2015: a hospital-based surveillance — Darboe S, Okomo U, Muhammad A-K, Ceesay B, Jallow M, Usuf E, et al. — Clinical Infectious Diseases — 2019.
Bloodstream infections at a tertiary hospital in the Gambia – a one-year retrospective study — Rahden P, Barrow E, Bah H, Bittaye SO, Nygren D, Badjan A — BMC Infectious Diseases — 2025.
Bloodstream infections and antimicrobial resistance in the Gambia: continuous surveillance from a tertiary care center — Nygren D, Andersson F, Barrow E, Bittaye SO, Bah H, Banja F, et al. — American Journal of Tropical Medicine and Hygiene — 2025.
Antimicrobial resistance (AMR) — The Institute for Health Metrics and Evaluation — 2021.
Performance standards for antimicrobial susceptibility testing — Clinical Laboratory Standard Institute — 2025.
Using an antibiogram profile to improve infection control and rational antimicrobial therapy in an urban hospital in the Gambia, strategies and lessons for low- and Middle-income countries — Darboe S, Mirasol R, Adejuyigbe B, Muhammad A, Nadjm B, De St Maurice A, et al. — Antibiotics — 2023.
