Trends of Antibacterial Resistance at the National Reference Laboratory in Cameroon: Comparison of the Situation between 2010 and 2017

INTRODUCTION: Antimicrobial resistance represents a growing public health threat. One of the World Health Organization's strategic objectives is "strengthening knowledge through surveillance and research." Sub-Saharan African countries are still far from achieving this objective. We aimed to estimate and compare the prevalence of antibacterial resistance in 2010 and 2017 in Cameroon. METHODS: We conducted a retrospective study on all clinical specimens cultured in Centre Pasteur du Cameroun (CPC) in 2010 and 2017. Data were extracted from the CPC's laboratory data information system software and then managed and analyzed using R. Bacterial resistance rates were calculated in each year and compared using chi-square or Fisher's tests, and relative changes were calculated. Outcomes included acquired resistance (AR), WHO priority resistant pathogens, some specific resistances of clinical interest, and resistance patterns (multi, extensively, and pan drug resistances) for five selected pathogens. RESULTS: A total of 10,218 isolates were analyzed. The overall AR rate was 96.0% (95% CI: 95.4-96.6). Most of WHO priority bacterial resistance rates increased from 2010 to 2017. The most marked increases expressed as relative changes concerned imipenem-resistant Acinetobacter (6.2% vs. 21.6%, +248.4%, p = 0.02), imipenem-resistant Pseudomonas aeruginosa (13.5% vs. 23.5%, +74.1%, p < 0.01), 3rd generation-resistant Enterobacteriaceae (23.8% vs. 40.4%, +65.8%, p < 10(-15)), methicillin-resistant Staphylococcus aureus (27.3% vs. 46.0%, +68.6%, p < 0.002), fluoroquinolone-resistant Salmonella (3.9% vs. 9.5%, +142.9%, p = 0.03), and fluoroquinolone-resistant Enterobacteriaceae (32.6% vs. 54.0%, +65.8%, p < 10(-15)). For selected pathogens, global multidrug resistance was high in 2010 and 2017 (74.9% vs. 78.0% +4.1%, p = 0.01), intensively drug resistance rate was 5.8% (7.0% vs. 4.7%; p = 0.07), and no pan drug resistance has been identified. CONCLUSION: Bacterial resistance to antibiotics of clinical relevance in Cameroon was high and appeared to increase between 2010 and 2017. There is a need for regular surveillance of antibacterial resistance to inform public health strategies and empirically inform prescription practices

Anopheles gambiae distribution and insecticide resistance in the cities of Douala and Yaoundé (Cameroon): influence of urban agriculture and pollution

Background: Urban malaria is becoming a major health priority across Africa. A study was undertaken to assess the importance of urban pollution and agriculture practice on the distribution and susceptibility to insecticide of malaria vectors in the two main cities in Cameroon. Methods: Anopheline larval breeding sites were surveyed and water samples analysed monthly from October 2009 to December 2010. Parameters analysed included turbidity, pH, temperature, conductivity, sulfates, phosphates,nitrates, nitrites, ammonia, aluminium, alkalinity, iron, potassium, manganese, magnesium, magnesium hardness and total hardness. Characteristics of water bodies in urban areas were compared to rural areas and between urban sites. The level of susceptibility of Anopheles gambiae to 4% DDT, 0.75% permethrin, 0.05% deltamethrin, 0.1% bendiocarb and 5% malathion were compared between mosquitoes collected from polluted, non polluted and cultivated areas. Results: A total of 1,546 breeding sites, 690 in Yaoundé and 856 in Douala, were sampled in the course of the study. Almost all measured parameters had a concentration of 2- to 100-fold higher in urban compare to rural breeding sites. No resistance to malathion was detected, but bendiocarb resistance was present in Yaounde. Very low mortality rates were observed following DDT or permethrin exposure, associated with high kdr frequencies. Mosquitoes collected in cultivated areas, exhibited the highest resistant levels. There was little difference in insecticide resistance or kdr allele frequency in mosquitoes collected from polluted versus non-polluted sites. Conclusion: The data confirm high selection pressure on mosquitoes originating from urban areas and suggest urban agriculture rather than pollution as the major factor driving resistance to insecticide