Picture: 123RF/Rusian Zagidulin
Picture: 123RF/Rusian Zagidulin

A growing body of scientific evidence suggests smokers are less at risk of contracting Covid-19 than those who do not regularly ingest nicotine. But the case for cigarettes (and other nicotine products) as a defence against the disease has so far gained little traction in SA.

At least 28 studies across a range of countries have found fewer smokers among Covid-19 hospital cases than in the general population. Greek academic cardiologist Konstantinos Farsalinos and others popularised the theory with a paper published in early April. They examined Chinese studies covering almost 6,000 Covid-19 hospital admissions, which showed that while smokers make up 26% of the Chinese population, only 6.5% of Covid-19 hospital admissions smoked.

Farsalinos and his collaborators noted that similar figures were found when the US Centers for Disease Control and Prevention (CDC) looked at 7,000 Covid-19 cases early in the pandemic. The centre found that only 1.3% of those hospitalised with the virus were smokers, while 14% of all Americans regularly use tobacco products.

Other researchers have subsequently reported similar findings. The study of Covid-19 cases in a Paris hospital, finalised two weeks ago, suggested that smokers are 78% less likely to “have an adverse outcome” from the disease. Another recent meta-analysis found that smokers are 82% less likely to be hospitalised with Covid-19 in the first place.

Dlamini-Zuma is not likely to be pleased with the news that her actions may have deprived South Africans of an effective means of protecting themselves against the depredations of the coronavirus

It should be noted that many of these scientific authors go out of their way to say that they are not proponents of tobacco consumption generally. Nor do they deny that once a smoker has been hospitalised for Covid-19 the outcome is likely to be worse. But if their conclusions are correct and nicotine is indeed a powerful prophylactic against Covid-19, the implications for SA are huge.

It is one of only three countries in the world to outlaw all trade in nicotine products in an effort to combat the disease (the others are Botswana and India). The thinking behind the ban has, however, been poorly explained. The minister who is reputed to have personally driven the ban, Dr Nkosazana Dlamini-Zuma, has made only one statement on the issue, in which she implied that the main problem in the context of the pandemic was the possible sharing of mouth fluids in the case of shared and hand-rolled cigarettes.

Dlamini-Zuma is not likely to be pleased with the news that her actions may have deprived South Africans of an effective means of protecting themselves against the depredations of the coronavirus. The medical establishment is also flustered by the findings, which means every possible alternative explanation has been advanced.

Critics argue that the studies are not representative and that in any case smokers admitted to hospital are ashamed to admit to the habit (“shy smokers”), which distorts the data. Others argue that case studies such as the Paris hospital one are based on data sets too small to be generalisable. It has also been argued that the comparisons between the number of smokers with Covid-19 and the number of smokers in the general population are crude and hence not scientific.

Peer review

A point that usually comes up is that these studies have not been peer reviewed. Until recently this was true: peer review typically takes at least six months, and Covid-19 has not been around that long. However, there is now a paper from Farsalinos that has been fast-tracked through the rigorous process and it corroborates earlier findings. It seems reasonable to require that counterintuitive claims require especially robust evidence — and we now have this. It is notable that none of those arguing that smoking is a risk factor for contracting Covid-19 has passed peer review.

What should not be denied by any scientist is that data is emerging that requires explanation. It is not good enough to simply dismiss the raw numbers as “not credible”, as a representative of the SA Medical Research Council did in a radio interview recently. The implications go beyond lifting the ban on nicotine products and raise questions about the actions of the SA government (the lockdown) and its willingness to truly engage with the science of Covid-19. Some might argue that nicotine was banned on a whim and the process represents a personal pet project, something that is the antithesis of a scientific approach.

The SA government has a far from unblemished record regarding applying science to health issues. Dlamini-Zuma, a former health minister, sat in the Mbeki cabinet (as foreign minister) while it so distressingly failed to implement available anti-HIV/Aids measures in favour of a misplaced faith in vitamins, nutrition and the African potato. It would be sad if a similar passivity were to prevent it engaging with the emerging evidence regarding nicotine and Covid-19.

• Christianson is a former African Business Writer of the Year who now covers a wide range of issues in politics, economics, business and the environment. He is a cigarette smoker.