Meg Tirrell: is Covid the flu after all?
EDITOR'S NOTE
Ladies and gentlemen...Meg Tirrell has graciously agreed to write today's column for us. Enjoy!
Is Covid the flu after all?
No, I don't mean in the sense that it's "just the flu." The chart below should dispel us of that (the blue number of deaths is Covid, the yellow is flu).
I mean: are we in for annual Covid shots the same way we (are supposed to) get annual flu shots?
If you ask Moderna, the answer is yes--an answer that added 12%, or more than $6 billion, to the biotech company's market value on Monday on the prospect of an annual revenue stream for its Covid vaccine. It turns out new variants of the coronavirus could mean the vaccine in its original form isn't enough in just the initial two doses. We might need annual boosters.
Moderna reported data this week suggesting its vaccine generates the same level of "good" neutralizing antibodies against the B.1.1.7 variant (associated with the U.K.) as against older strains, but against the B.1.351 variant--the South African strain--its neutralizing titers are sixfold lower. And a new paper just posted last night from the group of AIDS research pioneer Dr. David Ho suggests Moderna's neutralizing activity could even be 8.6-fold lower against the South African variant, and Pfizer's, 6.5-fold.
This doesn't mean the vaccine doesn't work against the South African variant, Moderna says, but it may mean the duration of protection is shorter. Hence: booster shots. "We may be condemned to chasing after the evolving SARS-CoV-2 continually, as we have long done for the influenza virus," as Dr. Ho's group said.
We could get even stronger information about the threat of these variants to the vaccines within days, when Johnson & Johnson reports results from its phase 3 vaccine trial. J&J ran the trial on three continents, in countries from here in the U.S. to Brazil and, importantly, South Africa, where the variants of concern are circling.
J&J's chief financial officer, Joe Wolk, told us on Squawk Box Tuesday that the company may report results on the vaccine by geography, if the variants have a real impact on efficacy.
What does this all mean for a return to normalcy? There's still a hope, espoused by Dr. Fauci and others, that if 70 to 85% of the U.S. gets vaccinated by fall, we can think about some kind of normal life again. It's not clear, given some people's hesitancy over getting the vaccine, whether we can get to that threshold.
Which makes it critically important to know if the vaccines prevent transmission. If they simply reduce the risk of getting symptomatic Covid by 95%, that's still amazing--but it won't mean the virus will die out through vaccination.
We also need to know what are called the "correlates of protection," or the level of immune response (antibodies or T cells) required to provide protection from disease. Once we know that, new or updated vaccines could be cleared for the market based on observing the immune response they generate, rather than through massive efficacy trials like the one J&J is running now. That's how flu shots are cleared for the market each year.
Speaking of the flu, that's at least been one bright spot this year; because of Covid social distancing practices, flu levels are at historic lows.
But to keep Covid from becoming a virus that, like the flu, we're perpetually chasing, Dr. Ho's paper notes, we must "stop transmission [now] as quickly as possible, by redoubling our mitigation measures and by expediting vaccine rollout."
A huge thank you to Meg for explaining all this so well. Stay tuned for a special "bonus" edition of the newsletter tomorrow on the wild GameStop story! -Kelly
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