Could Ozone Threapy be a Novel Strategy for Combating with Multi-Drug Resistant Bacteria?

Aim: This study evaluated the antibacterial effect of gaseous ozone on multi-drug resistant (MDR)
pathogens with regard to time dependency. Controlling infections with MDR bacteria became a big
challenge for health care professionals. Therefore, the major corcern should be altered to alternative
therapies.
Materials and Methods: The study was performed in Necmettin Erbakan University Meram Medical
Faculty Hospital, Department of Medical Microbiology Laboratory between 21 March to 15 April 2021. Ten
MDR bacteria were evaluated in vitro using in the Petri dishes at seven bacterial concentrations (102-
108 bacteria/dish). The ozone showed its efficacy on these MDR bacteria under the following conditions
applied: 40 μg/ml at 10, 20 and 40 minutes and control (no gas was used). After 24 hours incubation of
plates, the average colony counts for each exposure time of ozone were figured out and transformed to
Log10.
Results: Taking acccount the mean bacterial reduction (log10), the bactericidal effect of ozone was
determined on only methicillin-resistant Staphylococcus aureus, VIM-1 producing Klebsiella pneumoniae
and Carbapenem resistant-Acinetobacter baumannii in 10 minutes exposure. The optimum effect was
generally observed within 20 minutes on tested isolates. However, the MDR-Pseudomonas aeruginosa
showed a relatively lower response to ozone. All bacteria was inactivated over the level at 99% at the end
of the 40 min exposure to ozone.
Conclusions: The gaseous ozone showed satisfactory bactericidal activity on MDR pathogens and its
effect depens on exposure time and type of bacteria. Taken into account, the need for new approaches
for the control of microbial infections in the pandemic world, the optimization of ozone therapy should be
undertaken high priority and more in vivo studies are needed to support in depth understanding of the
ozone ef fect on the inactivation of MDR bacteria.