World No Tobacco Day 2020: How does COVID-19 affect smokers?

COVID-19 has already spread to 188 countries and is still wreaking havoc across the globe. Along with all other systemic diseases such as diabetes and high blood pressure, some doctors have also advised smokers to stay indoors. It is well known that smoking tobacco can lead to various diseases of the respiratory system, including lung cancer. The World Health Organization has stated that smokers could be more vulnerable to COVID-19 as well as to severe symptoms if they contract the infection. [caption id=“attachment_7540501” align=“alignleft” width=“380”]  Representational image. Image by Markus Spiske from Pixabay[/caption] Every year, 31st May is observed as World No Tobacco Day. This year, like every other,  doctors urge tobacco smokers to quit this harmful habit - but the emphasis now is even higher given that it could cause severe symptoms of COVID-19 in some people. Inversely, you may have recently come across news articles that claim smoking could potentially provide some protection against COVID-19. Here is some clarity on the connection between smoking and COVID-19.

Smoking kills ‘cilia’- the preventive shield of the airway 

According to a Chinese study published in February 2020, out of 1,099 patients who were infected with COVID-19 and were admitted into the ICU, 25.5% were smokers. The doctors and scientists believe that smokers were getting severe respiratory symptoms due to the absence of cilia in their airway. Cilia are tiny hairlike structures present in the airway lining. The cilia help keep the airway clean by removing the mucous and infectious agents before an infection acquires the lungs. The inhaled chemicals of cigarettes kill the cilia in due time. This makes them prone to new respiratory infections such as COVID-19. The absence of cilia can also lead to inflammation in the airway.

Smoking increases the levels of COVID-19 receptors in the body

The COVID-19 virus enters the human body by attaching itself to the ACE2 receptors which are present in high quantity on the surface of organs like the heart, lungs and even the entire gut lining. A group of scientists have concluded in their study that smoking can increase the levels of ACE2 receptors in the body. With the increase in the number of ACE2 receptors in the body and the absence of cilia, it can become easier for the virus to invade the body.

Nicotine may prevent COVID-19 infection

While every other doctor is warning the smokers about the ill-effects of smoking tobacco, a French study was published by Pitié-Salpêtrière which stated that smokers may be less prone to suffer severely from COVID-19 infection due to the positive effects of nicotine in this situation. They have found in their clinical and epidemiological trials that COVID-19 infection is a nAChR (Nicotine acetylcholine receptor) disease, which means the virus has a receptor for nicotine. Thus, when the SARS-CoV-2 (virus that causes COVID-19) enters the body, the nicotine in the body binds with it. This prevents the virus from binding with the ACE2 receptors in the body and thus deactivates it. The French scientists also suggested that nicotine patches, chewing gum and sniffing agents can be given to hospitalized patients and the general population to prevent them from getting the infection. However, scientists across the globe believe that the theory needs to go through several trials before even considering the use of nicotine as a therapeutic agent. Misuse of nicotine can be highly dangerous to the body and can cause brain deficits. For more information, read our article on COVID-19 and smoking. Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.