Vaccine effectiveness predictions
In light of the two recent situations in which fully vaccinated friends have gotten COVID-19 (see Maybe it is time for that booster shot? and Why is it still almost impossible to schedule a COVID-19 test? (at least in Maskachusetts)), I think it is time to look at what #Science said six months ago. “One year or 5? Doctors and drug companies increasingly disagree about when we’ll need COVID-19 booster shots” (Business Insider, June 16, 2021):
Insider spoke with nine leading experts, who took their best guesses about how long vaccine protection may last. Those predictions were quite a bit longer than what pharmaceutical companies suggest: Some experts said boosters probably won’t be necessary for another one to five years, while others questioned whether the general public will ever need another round of shots.
Early studies also suggest that the mRNA shots from Pfizer and Moderna offer more robust protection than natural immunity from an infection.
“Vaccines, actually, at least with regard to SARS-CoV-2, can do better than nature,” Dr. Anthony Fauci, the US’s leading infectious-disease expert, said in May.
“If I had to look at my crystal ball, it’s probably not sooner, hopefully, than a year after being vaccinated, for the average adult,” Dr. Peter Marks, director of the Food and Drug Administration’s biologics center, said during a recent webinar.
Other experts think protection may last far longer. Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia, estimates it could be three to five years. “I would predict that protection will last for a few years — protection as I define it, which is protection against severe to critical disease,” Offit told Insider last month.
Pfizer CEO Albert Bourla estimated in April that people would likely need booster shots within 12 months of getting fully vaccinated. That’d be as early as December for some in the US.
From University of Colorado, February 24, 2021, quoting the director of epidemiology for the Pandemic Response Office at CU Boulder:
… we know that the vaccine efficacy lasts at least eight to 10 months. But immune cell—called T-lymphocytes as well as B-lymphocytes—can stick around in the body for years, breaking into action quickly if the body ever encounters the same virus again. So, it’s likely that protection from severe disease and hospitalization could last for many years.
Two months after the vaccines were authorized for emergency use, in other words, scientists actually knew for certain that protection would last for 8-10 months.
“Underselling the Vaccine” (NYT, January 18, 2021):
Although no rigorous study has yet analyzed whether vaccinated people can spread the virus, it would be surprising if they did. “If there is an example of a vaccine in widespread clinical use that has this selective effect — prevents disease but not infection — I can’t think of one!” Dr. Paul Sax of Harvard has written in The New England Journal of Medicine. (And, no, exclamation points are not common in medical journals.) On Twitter, Dr. Monica Gandhi of the University of California, San Francisco, argued: “Please be assured that YOU ARE SAFE after vaccine from what matters — disease and spreading.”
Readers: Any favorite predictions from earlier in 2021 that you can find? One of the most interesting things about coronaplague is that Americans consider a discipline that is unable to make accurate predictions to be a “science”.
Full post, including comments