External quality assessment of bacterial identification and antimicrobial susceptibility testing in African national public health laboratories, 2011-2016

Perovic, O.; Yahaya, A. A.; Viljoen, C.; Ndihokubwayo, J.-B.; Smith, M.; Coulibaly, S. O.; de Gouveia, L.; Oxenford, C. J.; Cognat, S. B. F.; Frean, J. A.

doi:10.1101/740993

bioRxiv · 10.1101/740993

External quality assessment of bacterial identification and antimicrobial susceptibility testing in African national public health laboratories, 2011-2016

Perovic, O.·Yahaya, A. A.·Viljoen, C.·Ndihokubwayo, J.-B.·Smith, M.·Coulibaly, S. O.·de Gouveia, L.·Oxenford, C. J.·Cognat, S. B. F.·Frean, J. A.

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Abstract

BackgroundIn 2002, the World Health Organization (WHO) launched a regional microbiology external quality assessment (EQA) programme for national public health laboratories in the African region, initially targeting priority epidemic-prone bacterial diseases, and later including other common bacterial pathogens.\n\nObjectivesThe aim of this study was to analyse the efficacy of an EQA programme as a laboratory quality system evaluation tool.\n\nMethodsWe analysed the proficiency of laboratories performance of bacterial identification and AST for the period 2011-2016. Overall, 81 laboratories from 45 countries participated.\n\nThe National Institute for Communicable Diseases of South Africa provided technical coordination following an agreement with WHO, and supplied EQA samples of selected bacterial organisms for microscopy (Gram stain), identification, and antimicrobial susceptibility testing (AST). National public health laboratories, as well as laboratories involved in the Invasive Bacterial Diseases Surveillance Network, were enrolled by the WHO Regional Office for Africa to participate in the EQA programme.\n\nResultsWe analysed participants results of 41 surveys, which included the following organisms sent as challenges: Streptococcus pneumonia, Haemophilus influenza, Neisseria meningitidis, Salmonella Typhi, Salmonella Enteritidis, Shigella flexneri, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus anginosus, Enterococcus faecium, Serratia marcescens, Acinetobacter baumannii, and Enterobacter cloacae. Overall, 76% of participants obtained acceptable scores for identification, but a substantial proportion of AST scores were not in the acceptable range.\n\nConclusionIn the African Region, implementation of diagnostic stewardship in clinical bacteriology is generally suboptimal. This report illustrates that AST is poorly done compared to microscopy and identification. It is critically important to make the case for implementation of quality assurance in AST, as it is the cornerstone for antimicrobial resistance surveillance reporting and implementation of the Global Antimicrobial Resistance Surveillance System.

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Perovic, O., Yahaya, A. A., Viljoen, C., Ndihokubwayo, J.-B., Smith, M., Coulibaly, S. O., de Gouveia, L., Oxenford, C. J., Cognat, S. B. F., Frean, J. A.. 2019-08-20. External quality assessment of bacterial identification and antimicrobial susceptibility testing in African national public health laboratories, 2011-2016. https://doi.org/10.1101/740993

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