We would like to thank Dr. Rossato and colleagues for their comments on our paper “Tobacco and coronavirus: An opportunity to quit smoking”1.

To date, no evidence is available to show that smokers are at increased risk for SARS-CoV-2 infection (Covid-19); rather, there is evidence to suggest that both active and former smokers hospitalized for Covid-19 have more severe disease and a greater risk of death2–4.

As Rossato et al. rightly point out, several publications draw attention to the low proportion of active smokers among patients admitted for Covid-19. This has been confirmed in several series, and various explanations have been proposed. However, some studies do not specify whether the patient is an active or former smoker, and only a few differentiate former smokers from never smokers, with the result that many former smokers have been analyzed as never smokers. Furthermore, these data were self-reported, so some patients may have given an inaccurate picture of their habit. Finally, a patient’s smoking history may not be correctly documented in their clinical records. Our experience confirms these findings. Specifically, in our hospital, smoking history did not appear in the electronic medical records of 31% of the 178 patients admitted for Covid-19 between March and May 2020.

Studies that propose smoking as a possible “protective” factor raise it only as a hypothesis. The same article that Rossato et al. cite as an example of this possible “protective” effect in active smokers5 reports that these individuals are younger and have fewer comorbidities than former smokers, and suggests that this, and not their smoking habit, might explain the lower risk of hospitalization and death in this population. We believe that before we investigate the possible mechanisms that cause smoking to curtail the inflammatory response during Covid-19, this so-called “protective” effect should be confirmed in prospective and randomized studies.

In conclusion, then, we reiterate our previous conclusions, and we still firmly believe that there is not enough evidence to advise any unvaccinated patient to continue to smoke.