A new study from the University of Hiroshima has shed light on the paradoxical phenomenon that smokers are less likely to contract COVID-19, but more likely to require hospitalization if they do become infected. The study found that certain chemicals in cigarette smoke, specifically polyaromatic hydrocarbons (PAHs), can partially block the entry of the SARS-CoV-2 virus into human cells by reducing the formation of ACE-2 receptors on cell walls. The researchers hope to use this knowledge to develop a medication that can mimic the effects of PAHs without causing harm to human cells. However, they caution against using smoking as a preventative measure, as it has been shown to increase the severity of COVID-19 symptoms.
At the beginning of the COVID-19 pandemic, data from hospitals in France, Israel, and Germany showed that there were significantly fewer smokers among COVID-19 patients than in the general population. While the medical community was initially unable to explain this phenomenon, the University of Hiroshima’s study has provided a possible explanation. By examining how chemicals in cigarette smoke affect the human body, the researchers found that certain PAHs can block the entry of the SARS-CoV-2 virus into cells by reducing the formation of ACE-2 receptors on cell walls. This discovery could lead to the development of a medication that can mimic the effects of PAHs without causing harm to human cells.
However, the researchers caution against using smoking as a preventative measure, as it has been shown to increase the severity of COVID-19 symptoms. A study conducted in the United States found that smokers with COVID-19 were more likely to require hospitalization and had a higher mortality rate than non-smokers. The researchers at the University of Hiroshima also warn against using smoking as a preventative measure, stating that “as medical professionals, we can only emphatically answer no” to the question of whether one should start smoking to protect against COVID-19.
