Resistance of Anopheles gambiae sensu lato to Pirimiphos-methyl Insecticide in Kakamega County, Highlands of Western Kenya.

Background: Insecticide treated bed nets and Indoor residual spraying remains the principal interventional malaria control strategies. To achieve malaria disease eradication, vector control programmes that monitor insecticide resistance profiles are necessary. Objective: The study evaluated pirimiphos-methyl susceptibility of Anopheles gambiae sensu lato in Kakamega County, western Kenya. Methods: Adult Anopheles gambiae sensu lato mosquitoes were assayed using World Health Organization tube bioassay against 0.25% pirimiphos-methyl. Susceptible and non-susceptible populations were characterized to species-level using Polymerase Chain Reaction. Susceptible and resistant mosquitoes were further subjected to G119S Acetylcholisterase (ace 1R) mutation detection. Results: Anopheles arabiensis was the predominant species in all study population Mumias east (62%), Malava (68%), Ikolomani (77%) and Lurambi (82%). Results showed phenotypic susceptibility to pirimiphos-methyl. Mortality was low in Mumias east (80.6%) and high in Lurambi (89.0%). G119S mutations ranged from 3.0% to 8.9% in Anopheles arabiensis whereas G119S mutations were relatively low ranging from 0.0% to 3.1% in Anopheles gambiae s.s populations. Study populations tested were consistent with Hardy-Weinberg equilibrium (P>0.05). Conclusion: We observed pirimiphos-methyl resistance in Anopheles arabiensis and Anopheles gambiae s.s. study populations. Results showed G119S mutation in resistance population. Resistance monitoring and management are urgently required.

Assessment of knowledge of malaria and its control practices in mining and sugarcane growing regions of Western Kenya highlands.

Background: Despite upscaled control efforts, deaths and hospitalization due to malaria remained high in counties of western Kenya highlands. Objectives: This study assessed the knowledge of malaria in two rural communities, the control strategies they use, and their capacity to integrate the available control programs. Methods: A cross-sectional survey was carried out in two rural villages in November - December 2018. Focus group discussions and a questionnaire survey were carried out in 736 households. Frequencies and proportions were used for descriptive analysis while the Chi-square test was used to determine factors that were associated with knowledge of malaria at p ≤ 0.05. Results: Ninety-seven percent of the respondents had knowledge of malaria and this was associated with the level of education attained (χ2 = 30.108; p > 0.0001). Bed net ownership was at 86% and 92% correctly identified its use. Draining stagnant water (53.9%) was the most cited environmental management practice. Conclusion: There was awareness of the risk factors of malaria transmission in the study sites. The local communities must be mobilized and empowered through EIC for the control practises to bear fruit against malaria transmission. However, more sensitization needs to be done to optimize the use of malaria control practices.

Phenotypic and Genotypic Antibiotic Resistant diarrheagenic Escherichia coli pathotypes isolated from Children with Diarrhea in Nairobi City, Kenya.

BACKGROUND: The marked genome plasticity of diarrheagenic Escherichia coli promotes emergence of pathotypes displaying unique phenotypic and genotypic resistance. This study examined phenotypic and genotypic antibiotic resistant diarrheagenic Escherichia coli pathotypes among children in Nairobi City, Kenya. METHODS: In a cross-sectional study, diarrheagenic Escherichia coli pathotypes were isolated from stool samples and their phenotypic and genotypic resistance against eight antimicrobial agents assayed. RESULTS: Diarrheagenic Escherichia coli was detected in 136(36.4%) children. Most of diarrheagenic Escherichia coli that were resistant to ampicillin, ceftriaxone, streptomycin, gentamycin, ciprofloxacin, chloramphenicol, erythromycin and tetracycline, harbored citm, bla CMY, aadA1, aac(3)-IV, qnr, catA, ere(A) and tet(A) corresponding resistant genes. CONCLUSION: Antimicrobial-resistant genes are highly prevalent among phenotypic resistant ETEC pathotypes indicating a possibility of horizontal gene transfer in spreading antibiotic resistant genes among E. coli pathotypes.

Epidemiological patterns and antimicrobial resistance of bacterial diarrhea among children in Nairobi City, Kenya.

AIM: Determine the prevalence of enteric bacterial pathogens and their antimicrobial resistance among diarrheic children in Nairobi City, Kenya. BACKGROUND: Regardless of enteric bacterial pathogens being a major cause of gastroenteritis in children, their occurrence and antimicrobial resistance patterns reveals regional spatial and temporal variation. METHODS: In a cross-sectional study, a total of 374 children below five years presenting with diarrhea at Mbagathi County Hospital were recruited. Stool microbiology test was used to detect enteric bacterial infection. Antimicrobial resistance was determined using the disk diffusion method. RESULTS: Diarrheagenic E. coli (36.4%) was the leading species followed by Shigella (3.2%), Salmonella (2.4%), Campylobacter (1.6%), Yersinia (1.3%) and Aeromonas (1.1%) species. Escherichia coli pathotyping revealed that 20.9%, 4.0%, 10.2% and 0.5% of the study participants were infected with enteroaggregative E. coli (EAEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC) and enteroinvasive E. coli (EIEC) pure isolates while the prevalence of mixed pathotype infections was 0.3% for EAEC/EPEC/ETEC and 0.5% for EAEC/ETEC. Shigella sero-grouping revealed that 0.5%, 0.3%, 1.9%, and 0.5% were infected with Shigella boydii, Shigella dysentriae, Shigella flexneri and Shigella sonnei pure isolates. Shigella species and E. coli co-infection was detected in 2.4% of the children, specifically, 1.1% for EAEC/Shigella boydii, 0.5% for EAEC/Shigella dysentriae and 0.3% in each case of EAEC/Shigella sonnei, EPEC/Shigella flexneri and ETEC/Shigella flexneri co-infections. Most of the isolates were resistant to commonly prescribed antibiotics. CONCLUSION: There was a high prevalence of enteric bacterial pathogens and co-infection alters epidemiological dynamics of bacterial diarrhea in children. Continuous antibiotic resistance surveillance is justified because the pathogens were highly resistant to commonly prescribed antimicrobials.