Paris, Apr 24 (IANS): Researchers in France aim to test if nicotine patch could help prevent COVID-19 after initial observations showed that an ingredient in tobacco, probably nicotine, could put smokers at a lower risk of getting the disease.

The researchers are awaiting approval from French authorities to start clinical trial of nicotine patch on hospitalised patients and the general population at the Pitie Salpetriere hospital.

The initial study conducted at Pitie Salpetriere, part of the Hôpitaux de Paris, found that daily smokers have much lower probability of developing symptomatic or severe SARS-CoV-2 infection as compared to the general population.

According to the results, only 4.4 per cent of about 350 coronavirus patients hospitalised were regular smokers and 5.3 per cent of 130 homebound patients smoked. In the French population, the daily smokers rate was 25.4 per cent, said the study published in the journal Qeios.

The researchers also theorised that nicotine could help prevent the virus from infecting cells or that nicotine was preventing the immune system from overreacting to the virus.

"In order to prevent the infection and the retro-propagation of the virus through the CNS ( central nervous system), we plan a therapeutic assay against Covid-19 with nicotine (and other nicotinic agents) patches or other delivery methods (like sniffing/chewing) in hospitalised patients and in the general population," proposed researchers from Hopitaux de Paris, Paris and Pasteur Institute, Paris in a study which is also published in Qeios.

As the pandemic of COVID-19, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still under progression, the identification of prognostic factors is a global challenge.

Among epidemiological risk factors, the role of smoking, till date, is not clear.

Smoking has been initially found associated with adverse disease prognosis of COVID- 19, although this finding remains controversial.

Reported rates of current smokers among SARS-CoV-2-infected patients are heterogeneous, ranging from 1.4 per cent to 12.5 per cent.

The rates of current smokers remain however strikingly low for the middle-aged population.

A study in China, where the pandemic began, showed only 6.5 per cent of COVID-19 patients were smokers, compared to 26.6 per cent of the general population.

Additionally, these studies included mostly hospitalised patients, and the low rate of current smokers may be related to high rate of patients with comorbidities (smokers having been advised to quit) and thus resulting to COVID-19 severity.

The study also claimed of not advocating anyone to start smoking, as cigarettes have fatal health risks.