Most Covid Vaccines Will Work as Boosters, Study Suggests
Source: New York Times
People looking for a booster shot of a Covid-19 vaccine probably don’t need to fret about what brand it is: Many combinations of shots are likely to provide strong protection, according to a large new study. In a comparison of seven different vaccine brands, British researchers found that most of them prompted a strong immune response, with the mRNA shots from Moderna and Pfizer-BioNTech eliciting the largest responses. The study was published on Thursday in The Lancet.“These are welcome data for policymakers,” said Merry Voysey, a statistician at the University of Oxford who was not involved in the study.
“The most significant take-home message here is that there are a large number of excellent boosting options for third doses.” It’s too soon for researchers to say much about how well different vaccine boosters will work against the new Omicron variant, which has mutations that may allow it to evade some of the antibodies produced by existing Covid-19 vaccines. Some researchers suspect that people would need a very high level of antibodies to protect against it. All of the study’s 2,878 volunteers initially received two shots of either the AstraZeneca or Pfizer vaccines. (Both of those vaccines are authorized in Britain; shots by Pfizer, Moderna and Johnson & Johnson have been authorized in the United States.)
The researchers then tested seven different vaccines as boosters: along with AstraZeneca and Pfizer, they tried three brands that have been authorized in various countries: Johnson & Johnson, Moderna and Novavax. They also tried two shots that have not been authorized anywhere: an mRNA vaccine from CureVac, and a vaccine from Valneva made from inactivated coronaviruses. Finally, some of the volunteers received a meningitis vaccine as a control. After four weeks, the researchers collected blood samples from the volunteers and measured their antibody levels. They also looked for immune cells, known as T cells, that specifically attack other cells infected with the coronavirus.
Antibodies and T cell levels increased in people who received a Covid-19 booster shot compared with those who got the meningitis vaccine. The range was quite large, however. People who got the Valneva booster after a Pfizer vaccine saw only a 30 percent increase above the control group. But a Moderna booster produced at least a 1,000 percent increase. The new study also found that boosters increased T cells that recognize the coronavirus. Antibodies may be good at knocking the coronavirus out early in an infection, when the virus is colonizing the nose. But deep in the airway, T cells may provide a second line of defense.
Read more: https://www.nytimes.com/2021/12/02/health/covid-booster-shots-mix-and-match.html
Link to the publication in Lancet is here.
(note that displaying the link without embedding doesn't allow for clicking on it due to a parentheses that occurs in the link)
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Ty! 
that were shown during the FDA & CDC advisory panel discussions back in October, they were seeing those large boosts across the board - in some cases, participant immune responses hitting a good level in less than 2 weeks after a booster.
I still haven't heard if they determined whether the Moderna "effect" is due to it being a larger quantity of active biologic ingredient used and/or whether it was due to the longer timing between the first 2 doses (compared to Pfizer) and/or the luck of their active biologic itself.
Not sure what the reasons are, either. If I run across any explanations, I'll send them your way.
Got ##1 and 2 via the state, my county, and those were Moderna. 
Still possible they had more of it down there in the D.C. metro area early on, again thanks to NIH being down there and the fact that they helped work on Moderna's vaccine (I used to be back and forth down there on 355 and/or 270 on and off for years since I used to work for an agency in HHS and would go by NIH's complex). 
