Global Journal of Medical Research, F: Diseases, Volume 23 Issue 2

(Mimura et al., 2010). In addition, a retrospective observational study of elementary school students reported significantly lower cumulative absenteeism rates in classes where those CD gas-releasing agents were used than in classes where they were not used (Ogata & Shibata, 2009). The results of this study support the findings of these previous studies. A potential mechanism by which the CD gas-releasing agent suppressed COVID-19 infections is that CD gas, once dissolved in water, reduces the binding activity of the SARS-CoV-2 spike protein as demonstrated in in vivo experiments (Ogata & Miura, 2020, 2021). It has been suggested that this mechanism can reduce the viral infectivity of SARS-CoV-2 (Hatanaka et al., 2021). In summary, these findings suggest that the use of CD gas-releasing agents in elementary school classrooms could be linked to lower COVID-19 infections in students. The strength of this study is that it was a relatively large survey of many public elementary schools in the city. However, this study has several limitations. First, chlorine dioxide-releasing agents were distributed only to elementary schools that requested them, which may have biased the characteristics of the target population. Second, we did not have access to information from elementary schools located outside urban areas. Therefore, caution should be exercised when generalizing the results of this study. Moreover, the odds ratio could not be adjusted for confounding factors. Third, the route of infection was not considered. Hence, future randomized controlled trials should be conducted to evaluate the efficacy of CD gas-releasing agents against COVID-19. V. C onclusion A retrospective study in an urban elementary schools in Japan suggested that the use of chlorine dioxide gas-releasing agents may be linked to the reduced development of COVID-19 infections. Further studies are needed to prove a causal relationship. A cknowledgement We are appreciative to the elementary school officials and the school board for providing the data for this study. Funding The study was conducted and supported by a joint laboratory established by Juntendo University and its funder, Taiko Pharmaceutical Co., Ltd. Abbreviations SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; COVID-19, coronavirus disease 19; CD, chlorine dioxide. Conflict of Interest Yoshinori Kubo, Takanori Miura, Norio Ogata, Jo Shibata, and Takashi Shibata received a salary from Taiko Pharmaceutical Co., Ltd., which manufactures the chlorine dioxide gas-releasing agents (Cleverin®) used in this study. Yoshinori Kubo, Takanori Miura, Kaoru Obinata, Ken Hisata, Mitsuyoshi Suzuki, Eisuke Inage, Naotake Yanagisawa, Jo Shibata, Takashi Shibata, Toshiaki Shimizu belong to the Department of Mass Infection Prevention, which is funded by Taiko Pharmaceutical Co., Ltd. R eferences R éférences R eferencias 1. Aizawa, Y., Takanashi, S., & Ogimi, C. (2022, Nov 1). Updates on Coronavirus Disease 2019 in Children in Japan. Pediatr Infect Dis J, 41(11), e461- e467. https://doi.org/10.1097/inf.000000000000 3641 2. Azuma, K., Kagi, N., Kim, H., & Hayashi, M. (2020, Nov). Impact of climate and ambient air pollution on the epidemic growth during COVID-19 outbreak in Japan. Environ Res, 190, 110042. https://doi.org/ 10.1016/j.envres.2020.110042 3. Azuma, K., Yanagi, U., Kagi, N., Kim, H., Ogata, M., & Hayashi, M. (2020, Nov 3). Environmental factors involved in SARS-CoV-2 transmission: effect and role of indoor environmental quality in the strategy for COVID-19 infection control. Environ Health Prev Med, 25(1), 66. https://doi.org/10.1186/s12199-020- 00904-2 4. Chen, N., Zhou, M., Dong, X., Qu, J., Gong, F., Han, Y., Qiu, Y., Wang, J., Liu, Y., Wei, Y., Xia, J., Yu, T., Zhang, X., & Zhang, L. (2020, Feb 15). Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. Lancet, 395(10223), 507-513. https://doi.org/10.1016/s0140- 6736(20)30211-7 5. Cheng, V. C. C., Wong, S. C., Chen, J. H. K., Yip, C. C. Y., Chuang, V. W. M., Tsang, O. T. Y., Sridhar, S., Chan, J. F. W., Ho, P. L., & Yuen, K. Y. (2020, May). Escalating infection control response to the rapidly evolving epidemiology of the coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 in Hong Kong. Infect Control Hosp Epidemiol, 41(5), 493- 498. https://doi.org/10.1017/ice.2020.58 6. Chin, A. W. H., Chu, J. T. S., Perera, M. R. A., Hui, K. P. Y., Yen, H. L., Chan, M. C. W., Peiris, M., & Poon, L. L. M. (2020, May). Stability of SARS-CoV-2 in different environmental conditions. Lancet Microbe, 1(1), e10. https://doi.org/10.1016/s2666-5247 (20) 30003-3 7. Gates, D. J. (1998). The chlorine dioxide handbook (Vol. 2). Amer Water Works Assn. 3 Year 2023 Global Journal of Medical Research Volume XXIII Issue II Version I ( D ) F © 2023 Global Journals Relationship between COVID-19 and use of Chlorine Dioxide Gas-Releasing Agents in Elementary Schools