Authors: Christian A. Enwuru, Oluwatoyin O. Awoderu, Emelda E, Chukwu, Ebelechukwu E. Afocha, Lawal G Raman, Peter L. Gogwan, Uche T. Igbasi, Rosemary A. Audu
Background: Health experts promote the use of alcohol based hand rubs to contain the spread of microbes. The emergence of novel SARS-CoV-2 virus has brought a worsening public health challenge that re-enacted the importance of hand hygiene globally.
Objective: This study evaluated the antimicrobial efficacy of locally made alcohol-based hand rubes sourced from grocery shops within Lagos metropolis, Nigeria.
Methods: We conducted a laboratory based in vitro experiment, using 20 randomly sourced hand sanitizers against standard Escherichia coli (ATCC 25922) and three locally characterized Multi-drug-Resistant bacterial strains (Staphylococcus aureus (NIMR/NTCC/GP056), Klebsiella pneumonia (NIMR/NTCC/GN065) and Proteus stutzin - (NIMR/NTCC/ GN029). Reference standard, 60 % isopropanol was used as positive control. Test suspension method as per European standard PrEN12054 was employed. The Colony Forming Unit/mL (CFU/mL) at base line and after each contact time (15, 30 & 45 seconds) with samples was recorded. The Logarithmic reduction factor (RF) and percent reduction were computed and expressed using descriptive statistics.
Results: Out of the 20 solutions tested (10 sprays and 10 gels), 11 (55%) had standard efficacy of 5-Log10 reduction factor (6.7- 6.8) recommended at 15 seconds exposure time on the 4 bacteria. Out of such 7 (64%) were spray solution (L1, L3, L5, L10, L11, L12 & L16), while 4 (36%) were gel solutions (L9, L15, L18 & L20). Another 2 (10%) had relative time based efficacy at between 30 to 45 seconds exposure (L2 spray and L14 gel). Seven (35%) (L7 & L17 spray; L4, L6, L8, L13 & L19 gel solutions) failed the test. Escherichia coli and Proteus stutzin were more susceptible to the samples tested and produced higher RF.
Conclusion: About 45 % of the hand sanitizers had poor efficacy and this is quite high, especially in this era of pandemic. This report underscores the need for production policy review by the regulatory body. It is imperative to enforce quality management regime, particularly, internal and external production quality control. Periodic batch efficacy validation is necessary to ensure precision. Poor quality products must be actionable. We recommend this experiment be scaled up to national level and to cover major microbial pathogens.
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