Densità di popolazione e SARS-CoV-2: uno studio epidemiologico di urban health.

Despite SARS-CoV-2 transmission being a complex phenomenon, greater population density seems to be a risk factor. The aim of this study was to analyze through an epidemiologic urban health approach the relationship between population density and SARS-CoV-2 incidence using data which are comparable with regard to testing strategies. All 10,300 SARS-CoV-2 confirmed cases between October and December 2020 were included. We conducted separate analysis by gender standardizing and stratifying by age and month. In the Province Capital (p.d.=765 inhabitants/km2), standardized SARS-CoV-2 incidence rate was higher than the expected, both in men (SIR=1.17, 95%CI=1.12;1.22, p<0.0001) and women (SIR=1.20, 95%CI=1.15;1.25, p<0.0001). In municipalities with p.d. >200 inhabitants/km2, standardized SARS-CoV-2 incidence rate was similar to the expected (p>0.05). In municipalities with p.d. <200 inhabitants/km2, standardized SARS-CoV-2 incidence rate was lower than the expected, both in men (SIR=0.85, 95%CI=0.81;0.90, p<0.0001) and women (SIR=0.84, 95%CI=0.80;0.88, p<0.0001). Stratified analysis by months with likelihood ratio test showed heterogeneity of the p.d. effect in men and women (p<0.05). SARS-CoV-2 incidence rate seemed to be higher in most densely populated areas, both in men and women. Our results confirmed the great importance of restrictive measures as well as the importance of limiting the epidemic wave in the initial stages and could help guide pandemic management strategies according to urban context and population density.