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Camara, J.

Publications and source records attributed to Camara, J..

2 recordsLinked to original sources

Emergence of mpox in Guinea: sporadic clade IIa cases and a clade IIb upsurge

BackgroundMpox virus (MPXV) has caused recurrent outbreaks in West Africa. However, Guinea had not previously reported laboratory-confirmed cases or MPXV genomic data. MethodsSuspected cases were identified in the NZerekore region as well as in the Conakry (Sept 2024- Dec 2025) and confirmed by real-time PCR in regional and central laboratories, respectively. Whole-genome sequencing using nanopore technology was performed in-country, followed by phylogenetic and time-scaled evolutionary analyses. FindingsThe first mpox case was clinically diagnosed in September 2024 in the NZerekore region and laboratory-confirmed by the prefectural laboratory in Gueckedou. In total, seven cases were confirmed in Forest Guinea, of which five complete or almost complete MPXV genomes were recovered. All belonged to MPXV clade IIa. Genomic divergence, ancestral dating, and low APOBEC3-associated mutation frequencies were consistent with multiple independent zoonotic spillover events. In June 2025, one of the first mpox cases of an unfolding outbreak was confirmed in Conakry. Whole genome sequencing revealed MPXV clade IIb lineage G.1. By December 2025, the number of laboratory-confirmed mpox cases nationwide increased to 2,151. A total of nine outbreak strains were sequenced, all belonging to Clade IIb. The genomes clustered with contemporaneous genomes from Sierra Leone and showed high APOBEC3-associated mutation frequencies, suggesting sustained human-to-human transmission in the region. InterpretationThese data demonstrate simultaneous circulation of MPXV clade IIa and IIb strains in Guinea, likely resulting from zoonotic spillover and human-to-human transmission, respectively. Decentralised diagnostics and in-country sequencing facilitated rapid case confirmation and genomic surveillance, highlighting the importance of these critical capacities for outbreak preparedness and response. FundingGerman Federal Ministry of Health and the German Center for Infection Research (DZIF).

genomics↗

High burden and seasonal variation of paediatric scabies and pyoderma prevalence in The Gambia: a cross-sectional study

BackgroundScabies is a WHO neglected tropical disease common in children in low-and middle-income countries. Excoriation of scabies lesions can lead to secondary pyoderma infection, most commonly by Staphyloccocus aureus and Streptococcus pyogenes (group A streptococcus, GAS), with the latter linked to acute post-streptococcal glomerulonephritis (APSGN) and potentially rheumatic heart disease (RHD). There is a paucity of data on the prevalence of these skin infections and their bacterial aetiology from Africa.\n\nMaterials/methodsA cross-sectional study, conducted over a four-month period that included the dry and rainy season, was conducted to determine the prevalence of common skin infections in Sukuta, a peri-urban settlement in western Gambia, in children <5 years. Swabs from pyoderma lesions were cultured for S. aureus and GAS.\n\nResultsOf 1441 children examined, 15.9% had scabies (95% CI 12.2-20.4), 17.4% had pyoderma (95% CI 10.4-27.7) and 9.7% had fungal infections (95% CI 6.6-14.0). Scabies were significantly associated with pyoderma (aOR 2.74, 95% CI 1.61-4.67). Of 250 pyoderma swabs, 80.8% were culture-positive for S. aureus, and 50.8% for GAS. Participants examined after the first rains were significantly more likely to have pyoderma than those examined before (aRR 2.42, 95% CI 1.38-4.23), whereas no difference in scabies prevalence was seen (aRR 1.08, 95% CI 0.70-1.67). Swab positivity was not affected by the season.\n\nConclusionsHigh prevalence of scabies and pyoderma were observed. Pyoderma increased significantly during rainy season. Given the high prevalence of GAS pyoderma among children, further research on the association with RHD in West Africa is warranted.\n\nSummaryThis cross-sectional study of skin infections in The Gambia revealed prevalence of scabies, pyoderma and fungal infections in children <5 years of 15.9%, 17.4% and 9.7% respectively, with increased bacterial skin infections in the rainy season.

epidemiology↗