The hidden toll of the pandemic on nonrespiratory patients.

While many empirical studies have focused on the health consequences of COVID-19 for infected individuals, little attention has been given to its consequences for patients with nonrespiratory medical conditions. In this study, we apply machine learning and regression analysis techniques to complete-coverage administrative records of inpatient hospitalizations in Italy in 2012-2021 to investigate how the outbreak has impacted on the treatment of nonrespiratory patients in one of the countries most acutely affected by the pandemic. A comparison of hospital- and population-level excess deaths suggests that 53.7% of COVID-19 deaths occurred outside of hospitals. We interpret this as evidence of limited hospital resources, and we show that a higher number of hospital beds per capita is associated with a greater proportion of in-hospital deaths. We also document a 22.6% decrease in hospitalizations of nonrespiratory patients, more pronounced for patients in less severe conditions, and a conditional decrease of 0.5 days in the average length of stay for nonrespiratory patients. We attribute these changes to fear of infection and hospital resource limitations, and we show that the drop in admissions is more pronounced in areas that were more impacted by COVID-19 and had fewer hospital beds per capita. Our findings suggested that the pandemic's direct impact on infected individuals is just a fraction of the broader health losses in the population.

The complex interplay between weather, social activity, and COVID-19 in the US.

Empirical studies on the impact of weather and policy interventions on Covid-19 infections have dedicated little attention to the mediation role of social activity. In this study, we combine mobile locations, weather, and COVID-19 data in a two-way fixed effects mediation model to estimate the impact of weather and policy interventions on the COVID-19 infection rate in the US before the availability of vaccines, disentangling their direct impact from the part of the effect that is mediated by the endogenous response of social activity. We show that, while temperature reduces viral infectiousness, it also increases the amount of time individuals spend out of home, which instead favours the spread of the virus. This second channel substantially attenuates the beneficial effect of temperature in curbing the spread of the virus, offsetting one-third of the potential seasonal fluctuations in the reproduction rate. The mediation role of social activity is particularly pronounced when viral incidence is low, and completely offsets the beneficial effect of temperature. Despite being significant predictors of social activity, wind speed and precipitation do not induce sufficient variation to affect infections. Our estimates also suggest that school closures and lockdowns are effective in reducing infections. We employ our estimates to quantify the seasonal variation in the reproduction rate stemming from weather seasonality in the US.