Heat wave, COVID-19, and mortality excess in the 2022 summer: a cohort study on data from Italian surveillances.

ABSTRACT

We aimed to assess differences in the summer excess of mortality by COVID-19 history using data from the mortality and COVID-19 surveillances. We found 4% excess risk in 2022 summer, compared to 2015-2019. A mortality rate ratio of 1.59 (95%CI 1.39-1.82) for COVID-19 survivors compared to naive, was found. Both were higher in people aged [≥]75 years. During the July heat wave, the excess for COVID-19 survivors decreased and disappeared when excluding people living in nursing homes. Funding statementThis study was partially supported by the Italian Ministry of Health -CCM 2020 - "Sorveglianza epidemiologica e controllo del COVID-19 in aree urbane metropolitane e per il contenimento della circolazione del Sars-CoV-2 nella popolazione immigrata in Italia" and by the Ricerca Corrente 2023 HighlightsO_LIthe excess of mortality in COVID-19 survivors is not exacerbated by heatwaves C_LIO_LIan excess of mortality during the whole summer in COVID-19 survivors aged over 75 suggest that no harvesting effect is appreciable in the older population that survived COVID-19 C_LIO_LIFor COVID-19 survivors aged over 75, a lower mortality than the naive population was observed only during the July heat wave when we stratified by residency C_LI