A recent study posted to the medRxiv* preprint server assessed the impact of face masks on coronavirus disease 2019 (COVID-19) incidence among children aged between 10 and 12 years.
During the period of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant predominance in Finland, the use of face masks was recommended across the country in schools. However, there is insignificant data related to the impact of face masks in the prevention of COVID-19 transmission.
About the study
In the present study, the researchers compared the incidence of COVID-19 among children aged between 10 to 12 years, residing in different Finnish cities, with different recommendations regarding the usage of face masks in schools.
The team obtained the total number of COVID-19 cases from the National Infectious Disease Registry (NIDR) of the Finnish Institute for Health and Welfare. They also collected demographic information including the patient’s date of birth, sex, and residential area. The moving averages of 14-day case incidences were employed as a dependent variable. Furthermore, the team calculated the average percent changes (APC) occurring over one month.
The cities of Helsinki with a population of 6,61,887 and Turku with a population of 1,95,818 were compared for the present study since their baseline incidence of COVID-19 was comparable in August and September 2021. Helsinki had implemented face mask usage at schools while Turku had recommended face mask usage for individuals aged 10 years and above.
The team compared the 14-day incidences of COVID-19 among individuals aged seven to nine, 10 to 12, and 30 to 49 years.
The study results showed that there were no significant differences in APC values in August between Helinski and Turku. However, the APC value was higher in Turku in September and November while the APC value was higher in Helsinki in October.
Notably, the incidence of COVID-19 in children aged seven to nine years was similar to that in children aged 10 to 12 years, while no such similarity was observed for adults aged 30 to 49 years in the two cities.
Overall, the study findings showed that there were no substantial differences in the incidence of COVID-19 after wearing face masks in children aged between 10 to 12 years and residing in Helsinki and Turku.
medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.