A group of researchers from the Biosystems and Integrative Sciences Institute (BioISI) published a scientific article in Nature Communications that makes known factors that should be taken into account for the implementation of containment measures of respiratory diseases in primary and secondary schools. The article is based on computer simulations using detailed data on transmission patterns, mobility, or social contacts of various age groups in the Netherlands during the first two years of the COVID-19 pandemic. In addition to identifying useful factors to guide the implementation of measures in a future respiratory pandemic, the study helps identify measures related to the closure of schools that may have had more or less success in containing the pandemic between 2020 and 2021.
BioISI researchers reveal effects of school closures on COVID-19 infections
Ganna Rozhnova recalls that different age groups contributed to the spread of the pandemic at different times
"The group of adults was the one that contributed most to the spread at the beginning of the pandemic. But then, between the end of 2020 and the beginning of 2021, it was the group of adolescents that contributed most to the contagion. On the other hand, at the end of 2021, it was children in elementary schools who contributed most to the spread of the pandemic. What means that the widespread closure of schools produced different effects depending on the period in which it was applied", describes Ganna Rozhnova, a professor at the Faculty of Sciences of the University of Lisbon (Ciências ULisboa) and BioISI researcher who coordinated the study published in Nature Communications.
"Knowing these trends would have been useful to take targeted measures for the different age groups that, at each moment, are more influencing the spread of the pandemic," adds the researcher, who also works with the UMC Utrecht – university medical centre.
"We focused this study on schools, not only because they are very important in spreading, but also because the decision to close schools has an effect on the learning and well-being of adolescents and children"
Published under the title "Counterfactual evaluation of elementary and secondary school policies in the COVID-19 pandemic", the scientific article also features the participation of Benedetta Canfora and Rey Audie Escosio, students of PhD of Ciências ULisboa; Ana Nunes, professor at the Department of Physics of Ciências ULisboa; and also Otilia Boldea, researcher at the University of Tilburg in the Netherlands.
The study is distinguished not only by computational simulations, but also by data provided by the Dutch authorities, which reveal with great detail and at national and regional scale, the numbers relating to infections, hospitalizations, vaccinations, social contacts established by different age groups, mobility revealed by public transport between various regions, virus variants, immunity, among many other indicators. "We focused this study on schools, because they are very important in spreading, but also because the decision to close schools has an effect on learning and well-being of adolescents and children," explains Ganna Rozhnova.
According to the researchers, the closure of basic schools may not have had the desired effect at the beginning of the pandemic, as it was secondary schools that had the greatest impact on the spread.
With the data already worked, the researchers concluded that it would have been more beneficial to move towards a school closure that takes into account the age groups that, at each moment, more potentiate the pandemic spread. According to the findings of the study, the closure of basic schools may not have had the desired effect at the beginning of the pandemic, as it was secondary schools that had the greatest impact on propagation. On the other hand, it would have been more effective to close down basic schools at the end of 2021, since that was where the group most likely to spread contagion was located, while in secondary schools eventually some students were already vaccinated - and perhaps the closure was not justified.
"This study reveals which measures are most effective according to the types of schools, and reveals the factors that could be taken into account for the implementation of measures in schools if there is a new pandemic that spreads by respiratory way"
"This study reveals which measures are most effective according to the types of schools, and reveals the factors that could be taken into account for the implementation of measures in schools if there is a new pandemic that spreads by respiratory way", says Ganna Rozhnova.
The researcher at BioISI, who has made a career as an expert in modelling the spread of infectious diseases, continues to study the subject, but already in preparation for possible pandemics that may arise in the future. In addition to the impact generated by school closure days or sick leave, this new approach already covers issues related to the effects produced by the existence of ventilation and diagnostic tests, among other factors that may eventually condition contagion.