Abstract:
In the wake of the coronavirus disease 2019 (COVID-19) pandemic also known as
severe acute respiratory syndrome coronavirus (SARS-COV-2) pandemic, the World
Health Organization recommended the use of alcohol-based hand sanitizers rubs
(ABHRs) to curb transmission, leading to increased production and use. This has
posed a danger to production and use of poor-quality ABHRs. Emergence of resistant
strains of microorganisms due to the increased exposure to such hand sanitizers has
been observed in Salmonella typhimurium and Enterococcus faecium hence the need
to investigate the quality of these hand sanitizers and to determine the presence of
this resistance genes among clinical isolates in Kenya. This study investigated the
efficacy of alcohol-based hand sanitizers and the emergence bacterial tolerance and
resistance among Escherichia coli and Staphylococcus aureus clinical isolates pre
and peri- SARS-COV-2 pandemic outbreak in Nairobi, Kenya. Quality testing was
carried out against European EN 1500:2013 and Kenyan EAS 789:2013 Standards.
The study also compared the pattern of suspected resistance to ethyl alcohol by
Escherichia coli and Staphylococcus aureus. Purified non- pathogenic E. coli and S.
aureus samples (ATCC strains) were obtained from KEMRI Innovation &
Technology Transfer Division (KITTD). Clinical bacterial isolates for pre- SARS
COV-2 and peri- SARS-COV-2 pandemic were obtained from Kenyatta National
Hospital -Microbiology laboratories. The Escherichia coli were cultured in Eosin
Methylene Blue agar media while Staphylococcus aureus isolates were cultured in
Tryptic Soy agar. Genotypic analysis of resistant strains targeted the Qac A/B genes
using PCR for the genes in bacteria E. coli American Type Culture Collection
(ATCC) 25922 and S. aureus ATCC 25293, presence of these genes were
subsequently confirmed via sanger sequencing. Inferential statistics was used to
analyze the results for ANOVA and correlation coefficients using STATA, MEGA
11 and BLASTn tools were used for bioinformatics analyses. The study reported that
27.8% of the peri-pandemic sanitizers had less than 90% bactericidal reduction
activity as compared to 12.5% manufactured pre-pandemic. Only 25% peri-pandemic
ABHRs met the EAS 789:2013 acceptable limit of over 60% alcohol content.
Product adulteration with methanol was found in 20 % of the samples with only 5%
complying with FDA approval limit of <0.063% v/v methanol. The study found no
correlation between the total alcohol content and the efficacy of ABHRs. All E. coli
isolates tested negative for Qac A/B gene while 30.3% and 10.8% pre and peri-
SARS-COV-2 S. aureus isolates respectively tested positive for Qac A/B gene.
Sequencing of the bacterial isolates confirmed the presence of the genes of interest
(Qac A/B) in S. aureus isolates The study found that more substandard products were
produced during the pandemic. This raises a concern about the possible emergence of
alcohol resistant strains of microorganisms. Additionally, the study confirmed the
presence of biocide resistance genes in Staphylococcus aureus and lack thereof in E.
coli isolates. There was a reported reduction in the prevalence of Qac A/B gene
among the S. aureus bacteria in the population during the pandemic period as
compared to pre-pandemic period. The study therefore recommends an adequate
quality monitoring system to curb substandard biocides that have potential to lead to
pressure selection of antimicrobial resistance genes.
