Indoor Air Cartoon Journal, March 2020, Volume 3, #101
The majority of the coronavirus (COVID-19 virus known as SARS-CoV-2) health problems are related to the respiratory tract and lungs. Experts believe that viruses attached themselves to receptors to cause infection. The more significant number of receptors at the respiratory tract and lungs create a large surface area for potential infection to occur, depending on the concentration and toxicity of the viruses.
The good news is that the respiratory tract and lungs have the immunity system that provides antimicrobial defences to reduces the effect of deposited viruses on the receptors. The reduction in the effectiveness of the immunity system would increase the risk of infection occurring. The severity of the infection could lead to severe sickness or even death.
There is evidence in the literature supporting the fact that tobacco smoke contains toxic and carcinogenic chemicals that damage the immunity systems. The damage would make smokers more vulnerable to the COVID-19 virus attack. However, there is little or no scientific evidence to confirm the role of smoking history on the number of COVID-19 virus infected patients. Very little is also known about the contribution to the reported COVID-19 morbidity and mortality rates.
The established knowledge on the impact of tobacco smoke on immunity systems led to the development of the hypothesis for this article. Tobacco smokers exposed to coronavirus (COVID-19 virus) have a higher risk of being infected than non-smokers, with no pre-existing health or physiological problem, exposed to the same type and concentration of the virus.
Continuous or prolonged exposure to the toxic and carcinogenic chemicals, even at low concentrations, from tobacco smoke due to second and thirdhand smoking may also reduce the effectiveness of the defence of the immunity system. Secondhand smoking occurs when a person is not actively burning tobacco but inhaling the smoke from the person doing it around. Thirdhand smoking occurs when the toxic and carcinogenic chemicals linger in the air enough for a person that was not present when the person that actively burns the tobacco inhale the chemicals.
There is a high prevalence of secondhand and thirdhand smoking occurrences in the indoor environment. However, there is little or no knowledge on the contribution of second and thirdhand tobacco smoking on COVID-19 virus infection, morbidity, and mortality cases. Despite the highlighted gaps in knowledge on the relationship between tobacco smoking and the risk of being a victim of COVID-19, it is better to abstain from tobacco smoking because it damages the immunity system.
Do you want to know more about this topic? Read Cohen et al. (1993), Green et al. (2004), Wang et al. (2009), Martin et al. (2005), and Yamaguchi (2019) papers.