The effect of the use of disinfectants during COVID-19 pandemic on the bacterial contamination of dental unit waterlines

Abstract

Background: The emergence and spread of SARS-CoV-2 has increased environmental disinfectant usage to reduce the transmission of this virus. Ethanol 70%-90% and 5% sodium hypochlorite have the highest consumption for disinfection of various environmental surfaces during the COVID-19 pandemic. Dental unit waterlines (DUWLs) are more susceptible to microbial contamination due to their particular structure. This study aimed to investigate the effect of increasing the use of disinfectants during the COVID-19 pandemic on the bacterial contamination of DUWLs. Methods: During November (before the COVID-19 pandemic) and December (during the COVID-19 pandemic), a questionnaire was used to assess the frequency of disinfection of unit surfaces and other environmental surfaces and the type of disinfectants used. The water samples were collected from different parts of DUWLs. The gram staining method followed by the biochemical method was used to identify the desired bacteria. Results: The results showed that the frequency of disinfection of dental units increased 8 times in December compared to November. There is a significant inverse relationship between the frequency of disinfection of dental units surfaces and the bacterial contamination of DUWLs. Conclusion: The microbial load in different parts of the DUWLs was less than 200 CFU/mL. The American Dental Association (ADA) recommended and indicated the allowable microbial concentration and the appropriate quality and water used in these units.

Efficacy Assessment of Some Commonly used Disinfectants against Multidrug Resistant Bacterial Isolates from a Tertiary Healthcare Facility in Benin City, Nigeria

“…The emergence of methicillin resistant Staphylococcus aureus, MRSA, culminated in the incremental use of disinfectants in hospitals and public places since the 1960s [1][2][3][4][5][6][7]. An astronomical escalation in the application of disinfectants, antiseptic or biocides worldwide followed the SARS-CoV-2 (or COVID- 19) pandemic [8][9][10] and the resultant existence of an intense atmosphere of health insecurity [11]. Disinfectants are regarded as having a critical role in the control and blotting the chain of spread of infectious agents in the hospital and community.…”

“…Multidrug resistant bacterial species are usually organisms that have become resistant to a wide spectrum of antibiotics [17]. Resistant bacterial phenotypes are known to be demonstrable in all important groups of bacteria that initiate human disease [18] which also heightens the risks of contamination to the environment [19]. Disinfectants, antiseptics or biocides have extensively been employed in hospital care, homes and in aerial decontamination of public places that possess the potential for transmission of infectious agents [20][21].…”