After the nationwide school closure in March 2020, the rate of newly diagnosed asthma in children decreased significantly nationwide, and remained at a low level for the next 3 months. This was discovered through a survey conducted by Assistant Professor Naomi Matsumoto.
According to Okayama University, Professor Raito and his colleagues used Japan's largest medical information database, the RWD database, to analyze changes in the number of newly diagnosed asthma before and after the nationwide school closures, as well as a comparison of the number of newly diagnosed asthma and atopic dermatitis.The study period was from January 2017 to May 1, and 2021 children under the age of 5 were subject to data analysis with asthma and 15 with atopic dermatitis.
They found that newly diagnosed asthma in children fell by 59% after the nationwide school closures, and remained at low levels for the next 15 months.This trend was similar to that of rhinovirus and respiratory syncytial virus.In particular, children under the age of 2, who are more susceptible to respiratory viral infections, showed a large 72% decrease.
On the other hand, atopic dermatitis decreased by only 20%.There is a view that the decline in the number of new diagnoses was caused by refraining from seeing doctors during the corona crisis, but the difference in the rate of decline between asthma and atopic dermatitis could not be explained by this alone.
Professor Raito and his colleagues believe that the large decline in children under the age of two suggests a link between respiratory viral infections and the number of asthma cases in children.
