Schools opening and Covid-19 diffusion: Evidence from geolocalized microdata

Abstract

Are schools triggering the diffusion of the Covid-19? This question is at the core of an extensive debate about the social and long-run costs of stopping the economic activity and human capital accumulation from reducing the contagion. In principle, many confounding factors, such as climate, health system treatment, and other forms of restrictions, may impede disentangling the link between schooling and Covid-19 cases when focusing on a country or regional-level data. This work sheds light on the potential impact of school opening on the upsurge of contagion by combining a weekly panel of geocoded Covid-19 cases in Sicilian census areas with a unique set of school data. The identification of the effect takes advantage of both a spatial and time-variation in school opening, stemming from the flexibility in opening dates determined by a Regional Decree, and by the occurrence of a national referendum, which pulled a set of poll-station schools towards opening earlier or later September 24th. The analysis finds that census areas where schools opened earlier observed a significant and positive increase in the growth rate of Covid-19 cases between 2.5–3.7%. This result is consistent across several specifications, including accounting for several determinants of school opening, such as the number of temporary teachers, Covid-19 cases in August, and pupils with special needs. Finally, the analysis finds lower effects in more densely populated areas, on younger population, and on smaller class size. The results imply that school reopening generated an increase of one third in cases.

School-age Vaccination, School Openings and Covid-19 diffusion

“…This result is similar to Amodio et al (2022), who find a larger effect of the 2020 school 16 The average distance of a municipality without ICU beds from the nearest municipality with ICU beds is 3.1 km. 17 We obtained similar results when splitting the sample above and below the mean values.…”

“…Specifically, the coefficient measuring the impact of school opening in 2020 on Covid-19 diffusion is positive, significant and in line with the literature also in terms of magnitude. Compared to Amodio et al (2022), the coefficient is slightly lower as the time windows under consideration here are shorter. 13 The estimated coefficient for school opening in 2021 is not significantly different from zero, indicating that school opening is not associated to an increase in the growth rate of Covid-19…”

“…14 While in principle school opening may be considered as endogenous, in practice in 2020 it corresponded to a staggered design due to a national referendum for which some schools were used as polling stations (see Amodio et al, 2022 for details), while in 2021 a unique equal opening date was fixed for all schools, irrespectively of the number of cases or intensive care occupancy.…”

“…Specifically, we show that school openings in 2021 is associated to a differential impact when compared to 2020, with almost no effects on Covid-19 diffusion at the local level. The positive effect of school openings on Covid-19 diffusion, identified by Amodio et al (2022), appears to be fully mitigated by vaccination, with higher effects of vaccination in areas where the share of vaccinated school age population is lower and in areas with lower population density (that in the literature is often associated with higher and denser social interactions as we discuss below). In addition, we show by a counterfactual analysis that the diffusion of vaccination is associated to a reduction of hospitalizations in ICU of approximately 19%.…”

“…Given these patterns of Covid-19 cases and vaccinations across space, we will consider the case in which Covid-19 contagion spreads locally and then has further spillovers. Specifically, we will follow the strategy of Amodio et al (2022) and assume that contagion may be triggered by school openings in areas geographically close to the schools. In particular, we will assume that school openings affected the geographic micro-areas (i.e.…”