Smoking, SARS-CoV-2 and COVID-19: A review of reviews considering implications for public health policy and practice

Abstract

There is well-established evidence that smokers are more susceptible to both viral and bacterial respiratory infections 1,2 , as are those exposed to secondhand smoke 3. The World Health Organisation (WHO) has also highlighted smokers' hand-to-mouth action, smoking-induced lung disease, and the sharing of tobacco products such as waterpipes, as factors which may increase a smoker's vulnerability to SARS-CoV-2 infection and development of COVID-19 4. Evidence that chronic illnesses, especially respiratory and cardiovascular disease, are risk factors for worse ABSTRACT INTRODUCTION There has been significant speculation regarding the association between the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pathogen, coronavirus disease (COVID-19) and smoking. We provide an overview of the available literature regarding the association between smoking, risk of SARS-CoV-2 infection, and risk of severe COVID-19 and poor clinical outcomes, with the aim of informing public health policy and practice, particularly in England. METHODS Publications were identified utilising a systematic search approach on PUBMED and Google Scholar. Publications presenting a systematic review or meta-analysis considering the association between smoking and SARS-COV-2 infection or COVID-19 outcomes were included. RESULTS Eight studies were identified. One considered the relationship between smoking and the probability of SARS-CoV-2 infection, three considered the association between COVID-19 hospitalisation and smoking history, and six reviewed the association between smoking history and development of severe COVID-19. One study specifically investigated the risk of mortality. The studies considering risk of severe disease indicate that there is a significant association between COVID-19 and current or ever smoking. CONCLUSIONS This is a rapidly evolving topic. Current analysis remains limited due to the quality of primary data, although, early results indicate an association between smoking and COVID-19 severity. We highly recommend public health messaging to continue focusing on smoking cessation efforts.

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