Lack of association between patients characteristics and carriage of extended-spectrum β-lactamase producing Enterobacteriaceae in community settings in Blantyre, Malawi

Abstract Background: Infections caused by extended-spectrum β-lactamase (ESBL) producing bacteria are global health threat contributing to increased morbidity and mortality in resource-constrained countries. This cross sectional study examined factors associated with the carriage of ESBL-producing Enterobacteriaceae (ESBL-E) in community patients in Blantyre, Malawi. Methods: We collected rectal swabs and urine samples from randomly recruited participants and screened for ESBL-E on CHROMagar TM ESBL medium (CHROMagar, Paris, France). The ESBL-E isolates were identified using commercially acquired biochemical strips (Microbact™ GNB, Oxoid, UK) and production of ESBL was confirmed by the combination disk test using cefotaxime and ceftazidime disks with and without clavulanic acid. Antibiotic susceptibility test was done by the disc diffusion method and interpreted according to the recommendations of the Clinical and Laboratory Standards Institute (CLSI) 2019. Univariate logistic regression was used to evaluate association between ESBL-E carriage and the assosiated factors. To quantify relationships, dichotomous variables were compared using Pearson’s chi-square test or Fisher exact test as appropriate and continuous variables were compared using the Student’s t -test. Results were expressed as odds ratio (OR) with a 95% confidence interval Results A total of 50 community patients with ESBL-E phenotypes were identified from 300 adults recruited in the study, which gave a ESBL-E prevalence of 16.67% (50/300, 95% CI=12.43-20.91%). The mean age ±SD of participants was 32.41±12.07 years; range, 18-75 years and 54.33% (163/300) were women. on unadjusted logistic regression, no association between carriage of ESBL-E and community patient characteristics was observed. Conclussions The carriage of ESBL-E is prevalent in the community in Blantyre-Malawi. Nevertheless, factors associated with this carriage remain unidentified. Further investigations including large case-control and molecular studies using one health approach are required to confirm community-based transmission of ESBLs and to determine the factors, reservoirs and vehicles associated with the dissemination of ESBL within the community in Blantyre, Malawi.