Notable news on a day when the CDC just tweaked its recommendation on third doses. Previously most adults under 65 were told that they “may” get a booster if they choose. With the emergence of Omicron in South Africa, the guidance has changed. All adults now “should” get a booster.
CDC is updating its recommendation on #COVID19 vaccinations: everyone 18 yrs & older should get booster shot. We have much to learn about #OmicronVariant, but we do know that COVID-19 vaccines are our best tool to avoid serious illness & hospitalization. https://t.co/JvSr1hQoqy pic.twitter.com/SWok2Jas4P
— Rochelle Walensky, MD, MPH (@CDCDirector) November 29, 2021
If scientists are right that the many mutations on Omicron’s spike protein mean the vaccines will be less effective then it’s that much more important to maximize one’s neutralizing antibodies before the variant begins spreading. We’ll each need more in order to muster a decent immune response against infection by the new strain.
Of course, we’d be further along in the booster process if the federal science bureaucracy hadn’t spent week after week this fall fretting about vaccine equity and whether boosters were truly necessary for anyone except senior citizens. Many scientists, including Fauci, insisted that they were needed based on the alarming data showing immunity falling off after four or five months. But the FDA and CDC hemmed and hawed, reasoning that so long as the vaccines were standing up to severe illness then we might as well let people take their chances with a “mild” illness in which they merely suffer in bed for a week. As a result, two months passed before boosters were approved for all adults. That’s two months of catch-up we’ll be playing against Omicron.
Today’s announcement makes this new study timely, though. The dispiriting partisan polarization over vaccine policy means the study is destined to be celebrated on the left and challenged on the right, but there *is* some methodological room to challenge it. The number of boosted people who participated was tiny, just 33. And the study doesn’t show that total immunity is superior in boosted people, only that they end up with more neutralizing antibodies on average — in the short-term — than people with natural immunity do. Maybe it’s different longer-term. And even if it isn’t, people with natural immunity are likely better equipped to cope with new variants because their immune “memory” of the virus is more sophisticated than a vaccinated person’s is. Someone who’s had COVID has seen the entire virus and will evolve complex antibodies to try to anticipate its evolution. Someone who’s been vaccinated has seen only the spike protein. They might have more trouble hitting the curveball that’s presented by a new variant with lots of mutations.
But to the extent neutralizing antibodies are the yardstick for “protection” then this study says you’re much better off with a third vaccine dose than with natural immunity, at least in the first few weeks afterward:
Among this group of 33 fully vaccinated and boosted people, the median level of these antibodies was 23 times higher one week after the booster shot than it had been just before the tune-up dose.
What’s more, their median post-booster antibody level was three times higher than was typical for another group of people whose antibodies were measured a few weeks after getting their second dose of vaccine, when they’re close to their peak. And it was 53 times higher than that of a group of 76 unvaccinated people who had recovered from COVID-19 just two to six weeks earlier.
Even compared to a group of 73 people who had weathered a bout with COVID-19and went on to get two doses of an mRNA vaccine, the boosted group’s median antibody level was 68% higher.
“If I was going to Vegas, I’d bet on the booster rather than getting the virus to protect me,” the head of the study said. Here’s what the data looks like in graph form. The dashed black line in each column shows the median antibody level for someone in that category:
There’s no doubt that boosters are effective. There *is* doubt about how long they’ll be effective. Will protection fade again in four or five months? (Antibody levels always fade over time.) More importantly, will a third exposure to the spike protein give one’s immune system a stronger “memory” so that it can produce more sophisticated antibodies if and when it encounters Delta or Omicron?
Boosters are working like a charm in the UK so far:
This is a new chart format I’ve been working on for a few days. Lines still show age-groups, but they now change colour as people get boosters.
In October booster coverage was still low even in elderly. But by late Nov you can clearly see how boosters drive cases down 💉📉 pic.twitter.com/ezeTdldoMb
— John Burn-Murdoch (@jburnmurdoch) November 24, 2021
Here’s a reworking of a brilliant @PaulMainwood chart using the same format:
As boosters roll out, lines turns red, and then arc upwards as waning immunity is reversed.
You can already see early signs of 50-69s beginning to turn as they go from blue to … I wanna say lavender? pic.twitter.com/McJgXJWVD0
— John Burn-Murdoch (@jburnmurdoch) November 24, 2021
Case rates rose among the under-60 demographic in November but *fell* among the 60+ group, almost certainly thanks to the fact that they’re far more boosted than younger adults are. That’s true in the U.S. too, where 42.1 percent of senior citizens who’ve had two doses have gone on to get their third versus just 20.5 percent among the total adult population. I’m going to inch out on a limb and predict that those percentages will soon jump, especially among seniors, thanks to the panic over Omicron.
