Learning from Omicron
Has prevention failed?
We seem to have just passed the peak of COVID case numbers in LA County. As case numbers recede here and around the world, there is much to learn from the differences between this omicron wave and the waves that preceded it.
First, omicron spread much faster and infected many more people that prior variants. Both the slope and the height of the current surge of cases is higher than anything we’ve seen before. And the reported case numbers undercount actual infections, since they don’t count all the positive rapid home tests and all the infected people who never got tested. This high contagiousness and rapid spread placed massive strain on health care systems and other institutions. Hospital censuses rapidly increased but are already declining. Adding to the strain were the many healthcare workers who could not work because they were infected.
Another obvious difference from last year’s delta surge is that so many of us are vaccinated and boosted now. But omicron and delta also seem to cause very different illnesses. A smaller fraction of the patients hospitalized this winter were critically ill, and a smaller fraction required a ventilator. (Of course, a smaller fraction of a huge number of infected patients can still use up all the ICU beds.) And the biggest difference is the small fraction of omicron infections that resulted in death. Delta infected fewer people than omicron but killed many more people. Look at the differences between last winter and this winter on the graphs of cases and of deaths. At its peak, delta was infecting 15,000 people a day and killing 250 people a day. Omicron infected over 40,000 people daily at the peak and is killing about 60.
So at least compared to delta, omicron is much more infectious, and much milder. As I explained a month ago even a mild illness can lead to catastrophe if everyone gets it the same week. And omicron was a perfect pathogen for that. It spread like a shock wave, and even the tiny fraction that became seriously ill amounted to a lot of hospitalizations. The lesson is that omicron (like American Splinter Day) poses great risk to institutions – like hospitals and local 911 systems, but little risk to vaccinated and boosted individuals. Vaccinated and boosted individuals have very little chance of being hospitalized or dying due to omicron. I think that message hasn’t been emphasized adequately. Many of my vaccinated and boosted patients are still afraid that COVID poses a life-threatening danger to them. It doesn’t.
Another contrast of omicron to delta is the effectiveness of vaccines in preventing infections. The Centers for Disease Control and Prevention COVID Data Tracker website is particularly useful. Here is the graph of the rate of COVID-associated hospitalizations in 2021 in vaccinated and unvaccinated people.
As the winter surge in cases rolled over the nation, the blue line climbs as more unvaccinated people were hospitalized, but the green line stays flat. Vaccinated people are staying out of the hospital. Now here is the same graph for COVID infections rather than hospitalizations.
The blue line (vaccinated patients) stays relatively flat during the summer surge when the black (unvaccinated) line rises. But in December, omicron hit causing the blue line to rise steeply. The disappointing fact is that the vaccines, while still very effectively protecting against bad outcomes, are no longer preventing infection and transmission. To put that in more quantitative terms (using the data from the CDC site) unvaccinated adults have four times the risk of testing positive as adults who have received 2 vaccine doses. That means two vaccine doses are only 75% effective in preventing infection. And unvaccinated adults have thirteen times the risk of testing positive as adults who are vaccinated and boosted. That means that two vaccine doses plus a booster dose is 92% effective in preventing infection. Compare that to the measles vaccine which is 93% effective after one dose and 97% effective after two doses.
Before you throw your laptop across the room, Gentle Reader (may I call you GR?), please understand that I’m not arguing against the vaccines. I’ve been enthusiastically promoting vaccines and arguing against anti-vax misinformation in these posts for over 15 years. But omicron doesn’t care about that, and the fact that it’s slipping past our vaccines is just that. A fact.
So should we all get a fourth vaccine dose? Probably not. Preliminary results from a study in Israel show that a fourth dose doesn’t add much in terms of omicron protection. That makes sense. Omicron is infectious and mild. Three doses already protect against bad outcomes, and a fourth dose doesn’t seem to add much to protection against infection. Even the avuncular vaccine enthusiast Dr. Michael Osterholm when discussing the studies of a fourth vaccine dose said, “We can’t continue to boost our way out of this disease”.
This is all for the good if we can pay attention to what omicron is trying to teach us. The difficult lesson is that our attempts at prevention have failed spectacularly. Omicron has infected over a million people in LA County alone, a tenth of the population. And many of those were vaccinated and boosted. But what omicron also showed us was that the vaccines were fantastic at harm reduction. This will be a tough intellectual shift for doctors and public health officials. We think of vaccines as public health measures. We recommend flu vaccination for a healthy 20-year-old so that she doesn’t infect her grandfather. We vaccinate against measles so that herd immunity is maintained, and outbreaks are prevented. Omicron made those attempts futile and taught us that COVID vaccines are not public health measures like flu shots or measles vaccines. They’re like seatbelts – crucial tools for harm reduction for the individual who uses them.
For public health officials this might mean realizing that young healthy adults can make different and equally legitimate choices about whether to get vaccinated, especially men in their teens and twenties who have rare but serious side effects from the vaccine. It also raises serious questions about the benefit of booster doses for kids.
But most importantly it should lead us all to understand that the vaccinated do not need to be protected from the unvaccinated. Vaccinated people can transmit the disease. So being in an establishment that demands vaccine cards at the door just means you’re in an establishment with people who can transmit the disease. England and other European countries have learned this lesson, and dropped most of their pandemic related restrictions as the omicron wave receded.
After two years of trusting our health to increasing numbers of layers of protection, I know this can seem shocking and reckless, GR. I can sense you’re going to send me an email asking, “But what about future variants?” Attempts at predicting the future are notoriously imprecise, but we can be sure there will be more variants. This is scientifically proven because we have more letters in the Greek alphabet. But to spread substantially through the population, a future variant will have to outcompete omicron. That generally means that a future variant will have to be milder than omicron, or more infectious, or both. Evolution favors mildness. Putting your host in the hospital (or killing her) just means she’ll cough on fewer people. Giving your host a very mild runny nose and sore throat is much better for the virus. The host feels mostly fine. She hardly knows she’s sick before she’s infected a dozen workmates. So omicron will probably defend us against a more severe variant. And pi and rho and sigma are likely to be as mild as omicron or milder.
Harm reduction, rather than prevention, seems to be the path forward. That means living with omicron and with its future cousins forever, as we do with influenza and rhinovirus (the common cold). Having all gone through a very difficult two years, different people will adapt differently. Some will immediately rip off their masks and resume greeting long lost friends by licking their eyeballs. Others will continue to double mask outdoors staying a quarter mile away from the nearest person, conversing with their spouse only on Zoom. We must be gentle with ourselves and with everyone on the entire spectrum of reactions. The people on the former extreme have lost a lot because of the pandemic restrictions and crave a return to normalcy. The people on the latter extreme have been terrified for two years that COVID was going to kill them, and turning off fear is not easy.
So please be nice to people with the opposite reaction as you. And take a moment to be grateful that omicron came about when it did and spared us another winter with delta.
Learn more:
It's Over: England drops vaccine passports, mask mandates, and work restrictions (The Post Millennial)
Third Dose of Pfizer, Moderna Covid-19 Vaccines Offers Strong Protection Against Omicron (Wall Street Journal)
Episode 87: Hope Is Not a Strategy (The Osterholm Update – COVID-19 podcast)
Bringing Sanity to the Omicron Chaos: Three Doctors Weigh In (Honestly with Bari Weiss)
Fourth Vaccine Shot Less Effective Against Omicron, Israeli Study Says (Medscape)
COVID Data Tracker (CDC)
COVID-19 daily updates (County of Los Angeles Department of Public Health)