People who were not fully vaccinated this spring and summer were over 10 times more likely to be hospitalized, and 11 times more likely to die of covid-19 than those who were fully vaccinated, according to one of three major studies published Friday by the Centers for Disease Control and Prevention that highlight the continued efficacy of all three vaccines amid the spread of the highly contagious delta variant.
A second study showed the Moderna coronavirus vaccine was moderately more effective in preventing hospitalizations than its counterparts from Pfizer-BioNTech and Johnson & Johnson. That assessment was based on the largest U.S. study to date of the real-world effectiveness of all three vaccines, involving about 32,000 patients seen in hospitals, emergency departments and urgent care clinics across nine states from June through early August.
While the three vaccines were collectively 86 percent effective in preventing hospitalization, protection was significantly higher among Moderna vaccine recipients (95 percent) than among those who got Pfizer-BioNTech (80 percent) or Johnson & Johnson (60 percent). That finding echoes a smaller study by the Mayo Clinic Health System in August, not yet peer reviewed, which also showed the Moderna vaccine with higher effectiveness than Pfizer-BioNTech at preventing infections during the delta wave.
Again, at the time I got vaccinated, Pfizer’s numbers regarding effectiveness were slightly higher than Moderna’s, including for the elderly, and side effects were better with Pfizer. Right now I am not counting on Pfizer’s vaccine for protection against infection but hope it is still good enough against serious consequences. I have been back to double masking for some time.
Thank you for posting this interesting article, Old Mom. One quibble: you inserted the word “moderately” where the article didn’t say that. In fact, the article shows that Moderna was significantly more effective at preventing hospitalization. It was shown to be 4x more effective than Pfizer, and 8x more effective than J&J, which is really dramatically more effective (for example, with Moderna 95% effective at preventing hospitalization and Pfizer 80% and J&J 60%; if you had 100 people who had each of those vaccines and they were all infected with Covid, only 5 of the 100 Moderna recipients would be hospitalized, while 20 Pfizer and 40 J&J recipients would be hospitalized.). So those are very interesting studies and I would hope we have sufficient supplies of Moderna on hand to prioritize giving that out at this point (although obviously all of the vaccines are remarkably helpful).
I believe they are attributing the extra durability of Moderna’s vaccine potentially to two differences: higher dosing of the effective ingredient in the Moderna vaccine, and the longer timeframe used between the two doses. So who knows, perhaps if Pfizer started using 4 (or more) weeks between doses, they might be more similar.
I am not a math or statistics person, so I won’t explain this well, but that is not what this shows. The comparison is to no vaccine, not to each other. There is no scenario where 40 or 60 people out of 100 end up in the hospital. If, let’s say, roughly 5% of unvaccinated people who catch COVID end up in the hospital, you would normally expect 50 people out of 1000 to be hospitalized. Moderna cuts that by 95% so of 1000 people who catch COVID who’ve been fully vaccinated with a Moderna vaccine only 2.5 people (instead of 50) would end up hospitalized (and keep in mind they are also far less likely to be infected in the first place). At 80% effective at preventing hospitalization, for those infected but vaccinated with Pfizer, you would expect 10 (rather than 50) to be hospitalized, and for J&J, 20 would be. The way I did my math may be wrong - as I said I am not a statistics person (took it years ago, but remember very little) but I know your numbers are off as we don’t see that kind of hospitalization rates even among the unvaccinated - 95% effective means against the usual outcome; it’s not an absolute number that 5/100 will end up in the hospital.
Thank you for this! And you are right, my wording was off. But in both of our demonstrations, we see that Pfizer has 4x more hospitalizations than Moderna (in your explanation there are 10 Pfizer hospitalizations, and 2.5 Modernas; in my explanation there were 20 Pfizer to 5 Moderna). That was what I meant to emphasize, that they differ by a factor of 4. I think a lot of people think that 80% and 95% sound very similar–they are both very high percentages. But the results are really very significantly different. I am thinking based on these studies that if our whole country was vaccinated (100% compliance) with just one of the vaccines, we would have ended up with approximately 4x as many covid hospitalizations if the vaccine chosen had been Pfizer vs. Moderna (and 8x as many if it was J&J vs. Moderna). That’s a big difference across our population of 328 million people!
All of this is interesting, and I think it can inform choices going forward, but hopefully it doesn’t worry people with Pfizer & J&J because they, too, are highly effective!!! We are lucky to have all of these, particularly as they are all so safe in addition to effective.
I used to hear about studies of mixing and matching the vaccines (people who got Pfizer doses 1&2 could get Moderna as a 3rd and vice versa). I have not heard follow-up on this recently, and what I’ve heard from the White House is that we would potentially all stick with what we started with? I wonder what the rationale is/if there are any study results to support that).
The vaccine companies have much less incentive to study mix-and-match vaccine sequences, and the number of permutations of mix-and-match vaccine sequences is larger than the number of ways a single company’s vaccine can be given in terms of such things as number of doses.
So mix-and-match vaccine sequences remain mostly unstudied, unlike adding an additional dose to the same company’s vaccine (e.g. third dose of Pfizer or Moderna, or second dose of J&J). This does not mean that getting a different company’s vaccine later will be ineffective, just that it is unstudied.
Note that for other vaccines where periodic boosters are recommended (e.g. influenza, Tdap; also MMR in some situations), there is no advisory to get the same company’s vaccine that you got the last time (if you even remember which company’s vaccine you got the last time).
The two outgoing FDA vaccine leaders, as well as others, state vaccine data do not support boosters at this point in time.
“Current evidence does not, therefore, appear to show a need for boosting in the general population, in which efficacy against severe disease remains high”
ETA one of their points is to get more vaccine to global unvaccinated populations (before boosting), but don’t address whether or not there is actually more demand than vaccine supply right now. There are currently 7 WHO approved covid vaccines, 3 of which are marketed in the US.
Urgent Care clinics and ED’s are getting absolutely slammed in the past couple of weeks in the Twin Cities. Lots of Covid. Numbers of deaths are still down compared to some other states, but the way things are going I don’t see any way they aren’t going to go up soon.