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Published on: June 21, 2022
Effects of COVID-19 disinfection recommendations on microbial environment contamination: focus on emergency
Prabakar Vaittinada Ayar1,2,3, Angèle Cassagne1, Pradeebane Vaittinada Ayar4
1Beaujon Hospital AP-HP, Clichy, France (Emergency Department).
Objectives:
The coronavirus disease 2019 (COVID-19) has considerably changed the game in the field of hygiene. The aim of the study was to compare microbiological colonization present on the emergency physicians' stethoscopes and smartphones before and after the outbreak of COVID-19.
Material And Methods:
This was a prospective cohort study in 1 academic hospitals' emergency department. A microbiological analysis was conducted on the emergency doctors' stethoscopes and smartphones for a month in 2018 and 2021. Analysis concerned stethoscopes diaphragms and the most used surface of the cellphones screen around to the main button. The authors used a solid growth medium irradiated Count-Tact® 3P agar (CT3P) (BioMerieux, Lyon, France) for collecting samples. Results were obtained after 5 days of growth at 30°C to collect all the saprophytes environmental flora.
Results:
A total of 27 doctors were included in 2018 and 30 doctors in 2021. Stethoscope diaphragm contamination was very high in both period with a geometric mean (GM) without difference before and after COVID respectively, GM = 68 colony-forming unit (cfu) per 25 cm² (95% CI: 50-94 cfu/25 cm²) vs. 68 cfu/25 cm² (95% CI: 44-105 cfu/25 cm²), p > 0.05. Smartphones were cleaner than stethoscopes with a GM <50 cfu/25 cm² without significant difference between 2 periods, respectively GM = 45 cfu/25 cm² (95% CI: 34-59 cfu/25 cm²) vs. 31 cfu/25 cm² (95% CI: 20-48 cfu/25 cm²), p > 0.05.
Conclusions:
The study shows an urgent need to regularly inform of the hygiene of the medical tools and COVID-19 does not really bring improvements in the matter. Particularly in emergency department, where physicians examine several patients per day and can possibly transmit pathogens. Int J Occup Med Environ Health. 2025;38(6):611-20.
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