Nations with high smoking rate have low SARS-CoV-2 infection and low COVID-19 mortality rate.

On the other hand, the negative correlation between total cases and prevalence of male smokers appeared to be less robust: it was mildly significant at the 10% confidence level (column 1) when not controlling for real per capita GDP, while it was estimated to be positive and non-significant at ordinary confidence levels when controlling for real per capita GDP (column 2).

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