Omicron: Is “Less Lethal but More Contagious” Good?

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You know what I haven’t talked about lately? COVID-19. I mean, I’ve talked about the stuff surrounding it but I haven’t really talked about SARS-CoV-2 itself a lot. To be fair, the basic facts remain the same: the best way we can stop this pandemic is what we’ve now known for at least a year: get vaccinated, get your booster, wear your mask when you’re inside around strangers, keep your distance from others.

But there is this new variant, good old omicron. And with that comes new questions and concerns: the biggest fear for most people who have been doing everything “right” is the idea that SARS-CoV-2 could mutate in a way that lets it completely evade our vaccines. Good news! That hasn’t happened with omicron. In a study done in South Africa, the Johnson and Johnson single-dose vaccine drastically reduced hospitalizations for people with the omnicron variant, and no one died. There will continue to be breakthrough infections, because vaccines simply aren’t magical spells that protect you from viruses, but it looks like our current vaccines are good. Another new report this month finds that a third shot of the MRNA vaccine increases protection against omicron by 100-fold. Another new report suggests that two doses might not be great but that third shot is essential – that includes people like me, who got Johnson and Johnson as a first shot and MRNA as a second shot. I will be getting one more MRNA shot as soon as I’m eligible (in February). So it seems like a consensus is building that a third dose is critical for everyone to fight omicron.

The other question a lot of people seem to have is whether or not omicron is less severe, and less deadly than previous variants. It seems like the jury is still out on that – it has definitely killed people, but there’s compelling evidence that it may be gentler than Delta even though it seems to be transmitting more easily. That’s good, right? Well…not necessarily.

You may think or hope that the “end game” for COVID-19 is when it mutates to something akin to the common cold: everyone gets it eventually but it’s not a big deal for the vast majority of us. It’s possible that that could happen. After all, the virus doesn’t “want” to kill you because then it can’t be transmitted to a new host, so the most “successful” viruses don’t cause their hosts much fuss and jump from person to person, sometimes invisibly. Like herpes, for instance: most of the people who have herpes never even know it, so they take no precautions against it, which allows herpes to more easily jump to new hosts. It’s a sneaky, successful little jerk.

So is that what has finally happened with omicron? Well, probably not since it seems that people are still dying from it. But is it a good step in the right direction?

Recall that while it may be less deadly, it appears to be much, much more contagious. Data suggests that the number of people infected with omicron is doubling about every 3 days in South Africa where it was initially reported, but it’s doubling every 1.6 days in Denmark, and every 1.7 days in the UK, two places where there is much more sequencing done and thus the numbers are more likely to be accurate. If you’re wondering whether or not that’s bad, consider that back in June of this year Anthony Fauci pointed out that Delta cases were doubling in the US every two weeks, which was very upsetting at the time. So if we just go by those numbers, omicron is more than 8 times more contagious than delta.

But if it’s less deadly, it all evens out, right? Nope, that’s not how numbers work. Consider this chart from Gosia Gasperowicz at University of Calgary – the grey line at the bottom is the baseline variant, let’s say Delta. The blue line is what we’d expect to see if the virus becomes twice as lethal. The red line is what happens if it stays just as lethal but becomes twice as transmissible. And the green line is if it becomes twice as transmissible and TEN TIMES LESS LETHAL. Ten times. If we give that “faster but milder” variant enough time, it will absolutely destroy us.

In order for us to get to the “it’s just a common cold” stage, the virus would have to get substantially less lethal, especially if it’s spreading as quickly as omicron appears to be spreading.

And by the way, that’s just about lethality. It doesn’t factor in what we saw happen repeatedly in country after country throughout the past two years: even if people aren’t dying, they’re filling up the hospitals and pushing out other people who need care. They’re overwhelming the system and causing more non-COVID death and injury than we would otherwise see if we weren’t in a pandemic. And that’s exactly what looks to be happening in the places where omicron is surging – hospitals are filling up and healthcare workers are struggling to keep up.

I talk about this not to freak you out, but just because this is a complicated issue that I was interested in knowing more about and I figured it would be helpful to have it all in one spot. The basic message remains the same, as I said at the top of this video: get vaccinated, get your booster if you’re eligible, wear a mask when you’re inside with strangers, and try to keep your distance from strangers. I know you’re tired. So am I. But I’d rather be tired than the cause of my own or someone else’s otherwise easily preventable death.

Rebecca Watson

Rebecca is a writer, speaker, YouTube personality, and unrepentant science nerd. In addition to founding and continuing to run Skepchick, she hosts Quiz-o-Tron, a monthly science-themed quiz show and podcast that pits comedians against nerds. There is an asteroid named in her honor. Twitter @rebeccawatson Mastodon Instagram @actuallyrebeccawatson TikTok @actuallyrebeccawatson YouTube @rebeccawatson BlueSky

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  1. Authorities are talking up an eventual fourth booster while this bug remains an extant hazard. If so, it seems very worth doing. To my knowledge, no cold virus wreaks long-term effects of organ damage on its younger hosts after a nonlethal short-term infection, whereas COVID has a record of doing exactly that. Does Omicron leave long-term effects? I don’t think we have begun to discover the answer to that one yet, but it’s wise to act in the present to avoid becoming part of any future confirming data set.

  2. Yes 7 doublings in 2 weeks gives a 100 fold increase, another 2 weeks gives 10,000 fold, another 2 weeks gives 1 million cases per day. So Jan – Feb will see the big crunch in cases, with deaths following 2-4 weeks later. Against that, real growth curves usually do not remain in log phase for very long, otherwise we would all have been infected already.

    I would rather our leaders erred on the cautious side for once because once the numbers get anywhere near that it will already be too late. Of course that is not going to happen because of “the economy”.
    Ironically that very economy will probably tank anyway when that big wave hits.

    One small niggle, “omicron” is a short – o in Greek, omega is long -o.

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