A lot of people, including reputable sources, assume that smoking is negatively associated with Covid-19, particularly regarding survival rates. This was widely cited as an explanation for the gender discrepancy in China and for the high mortality rate in Italy. And I see that the WHO says “Smokers are likely to be more vulnerable to COVID-19”, based on theoretical considerations.
But it would appear that actual data shows the exact opposite - that smoking is protective against Covid - perhaps very strongly so. See e.g. here: “Based on the current scientific literature and on new epidemiological data which reveal that current smoking status appears to be a protective factor against the infection by SARS-CoV-2 …”, and “Compared to the French general population, the Covid-19 population exhibited a significantly weaker current daily smoker rate by 80.3 % for outpatients and by 75.4 % for inpatients. Thus, current smoking status appears to be a protective factor against the infection by SARS-CoV-2.”. I also see where the FDA is backing off an earlier position that smoking is harmful for covid.
It would make sense to me if smoking might be protective against getting infected in the first place, but that once seriously infected, with lungs under stress from the virus, it would then become a liability. This would be consistent with the 80.3% and 75.4% numbers cited above. But I see a study of some sort whose heading says “Active smoking is not associated with severity of coronavirus disease 2019 (COVID-19)” (I don’t subscribe to PubMed and can’t read the article itself).
So what’s the current state of the evidence?
[note: it goes without saying that it’s not worth starting smoking to protect against this virus, for a number of reasons, so comments along these lines are redundant.]
Don’t want to nitpick, but shouldn’t you be discussing smoking tobacco? I’ve heard discussion about a possible protective effect from nicotine. If that’s what you want to discuss, maybe tobacco use (chew, smoke) or nicotine use (patch).
Every time I’m asked whether I smoke, I answer “yes, but I do not use tobacco”.
Well yes, one theory of why smoking is effective is the nicotine in the tobacco. That’s the theory that the authors of one of the linked papers were putting forth, anyway.
My wife has her own theory. She says it’s because “everyone always keeps far away from smokers”.
This leads us to another question that I have wondered about since the start of this virus. Are there possibly thing we could inhale that would fight this virus. Like (virosydes). I would think there must be something that a human could tolerate well enough but it would kill the virus. The only bad thing about that would be killing it before antibodies were developed.
I’m not a medical expert, but my impression is that the the claim that “current smoking status appears to be a protective factor against the infection by SARS-CoV-2” is bullshit. At best, it’s highly speculative and highly suspect. First of all, tobacco smoking has long been associated with cardiopulmonary disease and weakening of the immune system, as well as various other forms of deterioration of the respiratory system, all of which would be huge COVID risk factors. The source of the stated claim – something called QEIOS – does not appear to be a reputable journal, but some sort of alternative fringe open-access publication whose impact factor I can’t even find anywhere – most Google results for it are references to itself or its Twitter feed. Moreover, the FDA isn’t “backing off” anything in any substantial way, but rather is stating that in the absence of the kind of respiratory damage typically associated with smoking, the risk it poses from COVID-19 is unknown, while also stressing that smoking can create worse outcomes from those who get the disease.
For the original claim to have any real credibility whatsoever, I’d like to see corroboration from an independent study published in a reputable peer-reviewed journal, and – no pun intended – I’m not holding my breath for that.
Finally, there was a meta-study conducted in mid-March that did suggest, albeit tentatively, the expected conclusion that smokers are at increased risk from COVID-19:
In conclusion, although further research is warranted as the weight of the evidence increases, with the limited available data, and although the above results are unadjusted for other factors that may impact disease progression, smoking is most likely associated with the negative progression and adverse outcomes of COVID-19. http://www.tobaccoinduceddiseases.org/COVID-19-and-smoking-A-systematic-review-of-the-evidence,119324,0,2.html
All that (including the meta-study) relates to the progression of the disease in those who are already infected with Covid-19. The key question is over apparent evidence that smokers are significantly underrepresented among those who get infected to begin with.
FWIW, here’s a comment on the state of current evidence from a seemingly-reputable guy named Francois Balloux. (There’s a response attached suggesting that underrepresentation of smokers may be due to poor data collection.)
I wouldn’t be surprised if the numbers are off. OTOH smoking coincidentally reducing the severity of the virus is not so incredible, after all we sometimes treat cancer with poisons. Many medications are dangerous when wrongly used. So if it is, it is. It’s not going to result in doctors telling people to take up smoking for their health.
One of the early sets of numbers for co-morbidities showed little association with smoking as well. OTOH, it seemed that being an ex-smoker was associated with significantly worse outcomes. I puzzled about this for a while until I realised that many smokers don’t give up willingly. The reason that they were forced to give up smoking is likely advanced disease. But the statistics may easily show a weird correlation.
Given there is still a lot of puzzlement about the reasons for the characteristic pattern of deaths from Corvid-19, it is quite possible that damage from smoking is simply not especially relevant to the disease’s progress.
Though again, the evidence seems to suggest that the damage from smoking is relevant to the disease’s progression, but that smokers might be less likely to get infected to begin with.
Re your first paragraph, I wonder if it’s possible that the smoking itself is a positive but the damage to the body caused by smoking is a negative. If so, then ex-smokers could be worse off than current smokers, since they still have much of the damage caused by their prior smoking but not the beneficial effects of the smoking itself.
Is there some weird reason that smokers may be less susceptible to catching COVID-19?
What is the difference in outcomes for smokers if they do get it?
The answer to #2 is quite clear: outcomes tend to be far worse for smokers.
The answer to #1 is that it’s currently unknown, but the implication from the article is that such a conclusion, as I said earlier, is highly speculative at this time and really rather suspect, because it goes against the grain of everything that is known about the effects of smoking, such as compromising the body’s immune system and stuff like this (from the above cite):
Smoking hinders the function of cilia, small hair-like projections that line the respiratory tract, which “beat up and out any kind of particles that are inhaled,” said Kathryn Melamed, a pulmonary and critical care physician at UCLA Medical Center.
Smoking also inhibits blood cells that would otherwise clean and repair damaged lungs, she said.
But who knows. Having lungs that are coated with tar, and that destine the subject to a likely premature death, may present a hostile environment to the virus. It just strikes me as more likely to be statistical bias than an actual effect.
Francis, I follow your logic about ex-smokers, but I would argue that even current smokers likely have much the same kind of damage, though perhaps to a lesser extent, and they may not even know about it, but it nevertheless makes them more vulnerable.
Yes. I should try to find it again, I think the bit I forgot to mention was that these numbers were for hospital admissions. So you needed to be sick enough to be admitted. This would probably act as something of a filter in the statistics, emphasising those with much more damage.
The point about why one has given up smoking extends to more than just smoking induced damage. Smoking may only be part of the story behind the condition that has caused a forced cessation. Here, in our public health system, whilst access to care is guaranteed, there are waiting lists for procedures, and those lists get prioritised. Cardiac patients needing surgery are told that whilst they continue to smoke, they will always remain at the bottom of the list.
It’s been suggested elsewhere that publicly smoking tobacco fosters social distancing because who want to approach reeking stinkpots? To test the idea, supply one group with vile cigars and smear a control group with fetid feces. See which group has higher COVID infection rates. It’s scientific.
Possibility 1: Bad or non-representative data
Possibility 2: The people who were tallied were all over 65. If smoking ain’t already killed them, then they might have good genetics that supersede their bad habit.
Possibility 3: Reality is, sometimes, weird.
Arguing against the data fluke argument, and (to a lesser extent) against the data error argument, is that (per the claim, at least) the discrepancy has been observed in several countries, i.e. China, France, and (IIRC) the US.
My sources say that a group of ravens is not called a flock: “A group of Ravens can have three different names depending on the activity of the group; a constable, an unkindness, or a conspiracy.” Somewhere else I also found a storytelling. Just to nitpick But if it was crows, you’d have murder by a murder of crows. That sounds cool
Indeed. But “murder by a murder of crows” just didn’t work. So ravens it had to be. I like ravens.
But if it was crows, you’d have murder by a murder of crows. That sounds cool 