Omicron Knowns and Unknowns
Tuesday, December 21, 2021
You’re luxuriating on your patio on a beautiful unfinished cedar lawn chair when you get a splinter in your finger. What are the most likely outcomes? By far the most likely outcome is that you fish the splinter out of your skin with tweezers, apply a little rubbing alcohol to sterilize the puncture wound, and never think about it again. After all, most splinters don’t cause infections. It’s much less likely, but possible, that a few days later you’ll have some redness at the puncture site, apply a topical over-the-counter antibiotic for a few days, and that cures it. Very rarely, the redness might continue to spread, and you might need to see your doctor for an antibiotic prescription. But what if you have diabetes? Or what if you just had chemotherapy and have very few white blood cells? There’s an extremely small chance that you’ll be hospitalized for intravenous antibiotics or need surgery to drain pus from the infected tissue.
And what if every single person in the country got a splinter in their finger on the same day, the forever thereafter remembered American Splinter Day? Well, again, most people would take care of it themselves, have no bad consequences, and never seek medical attention. But if even one in a thousand splinters leads to a doctor visit, that’s hundreds of thousands of people trying to see their doctors the same week. If even one in ten thousand need intravenous antibiotics, that’s tens of thousands of people needing a hospital bed the same week.
It’s not just that there might not be enough resources to manage this splinter tsunami, it’s that all the people having car accidents, strokes, and heart attacks that week might not be able to get prompt care. The problem would not be primarily medical. We know how to treat skin infections. The problem would be logistical. Who gets seen first? Do elective surgeries get postponed? Do we start giving IV antibiotics at home to the less-sick patients to keep hospital beds open?
These may be the challenges that omicron poses in the next few weeks. We’ve gotten much better at treating COVID in the last two years, both in an out of the hospital. And we’re very good at preventing bad outcomes through vaccinations. Hospitalizations and deaths from COVID are still largely limited to the unvaccinated. But the rapidity that omicron has spread in other countries raises the concern that a lot of people in the United States will get it at the same time.
Data from countries in which omicron was first detected suggests that it is 2 to 3 times more transmissible than delta. (And recall that the delta variant was constantly referred to as highly transmissible when it was first detected.) Countries in which omicron became the dominant strain had case doubling times of about two days! The graphs of daily case counts in these countries shot up almost vertically, making epidemiologists lightheaded and making engineers realize they need a log scale. Just yesterday, the Centers for Disease Control and Prevention (CDC) announced that omicron is now responsible about three quarters of the nation’s new cases.
If you want the technical details, terrific reviews of the early data on omicron are in last week’s UCSF’s Department of Medicine Grand Rounds and the Center for Infectious Disease Research and Policy’s (CIDRAP) podcast.
The good news is that the evidence so far hints that omicron might cause milder illness than delta. Even the avuncular Michael Osterholm says that the preliminary data support this conclusion. But there are caveats. The earliest patients in the countries who’ve already had many omicron cases are predominantly travelers, who tend to be younger and healthier than the general population. So the fact that they’re having better outcomes may have as much to do with who they are rather than the strain that infected them. We’ll have to see when omicron sweeps through older communities if outcomes are truly better than with delta. But as I hope I explained above, even a much milder illness can temporarily cripple a health system if enough people get it simultaneously.
Also concerning is the finding that omicron is infecting vaccinated people at a higher rate than delta. Fortunately, booster shots restore excellent levels of protection.
So what would we do if we were warned about American Splinter Day a week or two in advance? We would ask as many people as possible to protect themselves by putting on heavy work gloves. Yes, the risk to any one individual is probably tiny, but every thousand splinters that are prevented opens another slot for a doctor visit. Every ten thousand splinters prevented keeps a hospital bed open. (This analogy would obviously be stronger if splinters were contagious, since not catching COVID also prevents you from infecting others. But I’m not one for finding a stronger analogy. I’m for stretching bad analogies until they break.)
So get your booster ASAP. You should also know that the CDC is now recommending that unvaccinated people get the Pfizer or Moderna vaccines preferentially and avoid the J&J vaccine unless it’s the only alternative.
Will it be like this forever, with new variants appearing every few months making omicron look slow in comparison, keeping us fearful of another coming wave of infections? No. Pfizer’s Plaxlovid, a pill containing two antiviral medications, was found to decrease hospitalizations and virtually eliminate deaths due to COVID when given promptly after infection. It should be available in January, or whenever the FDA gets back from its coffee break. Besides saving lives, Plaxlovid will decompress hospitals, simplify treatment, and let us all get back to rubbing unfinished cedar lawn chairs with impunity.
And now that I’ve broken the analogy beyond repair, it remains for me only to wish those who are celebrating a merry Christmas, and to wish us all good health and joy in 2022.
Learn more:
Omicron Variant Accounts for 73% of U.S. Covid-19 Cases, CDC Says (Wall Street Journal)
Omicron in Mid-December: What Have We Learned and What Does it Mean? (UCSF Department of Medicine grand rounds)
Episode 81: The Early Data on Omicron (CIDRAP COVID-19 podcast)
A brief chart reviewing essential data about omicron so far (Eric Topol, Twitter)
CDC Endorses ACIP’s Updated COVID-19 Vaccine Recommendations (CDC Media Statement)
Looking Ahead: An Effective Oral Drug for Treatment of COVID-19 (More@MedLetter, The Medical Letter blog)