Lung damage in SARS‐CoV‐2 patients: An autopsy study in the era of vaccination

Aims The contribution of SARS‐CoV‐2 infection on lung damage and the effect of vaccination on either containing the number of deaths or mitigating lung damage has not been systematically investigated. Methods Post‐mortem analysis was performed among consecutive in‐patients with COVID‐19 deceased in the Province of Trieste (2020–2022). The outcomes of the study were (i) rates of in‐hospital mortality, (ii) contribution of COVID‐19 to death, (iii) histological extent of lung injury and (iv) impact of vaccination. Results A total of 1038 consecutive hospitalized patients who died with SARS‐CoV‐2 infection were autopsied and deep histological analysis of the lungs was performed in a randomly selected sample of 508 cases. Among them, SARS‐CoV‐2 infection was (a) the cause of death ( n = 90), (b) contributing to death ( n = 304) and (c) an accompanying feature ( n = 114). The incidence of SARS‐CoV‐2 infection as the primary cause of mortality decreased over time (23.8% in 2020, 20.9% in 2021 and 7.9% in 2022). On multivariable analysis, vaccination (any dose) was independently associated with lower rates of death related to SARS‐CoV‐2 infection (HR .15, p < .001), after adjusting for other independent predictors. A total of 172 patients were vaccinated at least with two doses at the time of death: 93% triple‐vaccinated, 7% double‐vaccinated. On histological analysis, vaccinated patients had a greater frequency of pneumonia severity score 0 and 1 (20.3% vs. 5.4% and 20.9% vs. 7.7%, p < .001, respectively), and a substantially lower proportion of pneumonia severity score 3 (26.2% vs. 55.1%, p < .001) compared to unvaccinated patients. Conclusions COVID‐19 vaccination has substantially reduced rates of death related to SARS‐CoV‐2 infection over time and may have the ability to mitigate lung damage.