WASHINGTON — Now that three booster shots have been approved and recommended by public health authorities, including the CDC, many people are wondering which one they should get.
On social media, posts are spreading that claim to rank the boosters for each of the vaccines. To confirm whether this graphic is accurate, the Verify team spoke with two medical experts, and looked over studies from NIH.
QUESTION:
Does preliminary data from NIH indicate that certain boosters create more antibodies than others?
SOURCES:
- Dr. Amesh Adalja, Senior Scholar at the Center for Health Security at Johns Hopkins University
- Dr. William Schaffner, Professor in Preventive Medicine and Health Policy at the Department of Health Policy at Vanderbilt University
- NIH Study, "Heterologous SARS-CoV-2 Booster Vaccinations - Preliminary Report"
- Centers For Disease Control and Prevention, "CDC Expands Eligibility for COVID-19 Booster Shots"
ANSWER:
Yes. While the study has limitations -- including a small sample size -- it so far indicates that mRNA boosters generate a significantly larger antibody response.
This is especially pronounced when it comes to those who received the Johnson and Johnson vaccine. Following this vaccine with an mRNA booster, results showed a much larger antibody response.
WHAT WE FOUND:
At this point, the FDA has authorized and the CDC has recommended boosters for those who received all three vaccines. The boosters are available for the following people:
Johnson And Johnson Vaccine Recipients:
- Those 18 and older who are at least two months past their initial vaccine
Moderna and Pfizer Vaccine Recipients:
- Those 65+, 6 months after initial doses
- Those 18+, who live in long-term care settings, 6 months after initial doses
- Those 18+, who have underlying medical conditions, 6 months after initial doses
- Those 18+, who work or live in high-risk settings, 6 months after initial doses
Mixing-And-Matching:
- The CDC is also allowing mixing-and-matching of shots, meaning that someone can receive one vaccine, and then when eligible, switch to a booster of another brand.
WHICH BOOSTER WILL CREATE THE LARGEST ANTIBODY RESPONSE?
Since mixing and matching is permitted, people are searching for the booster that will create the maximum impact. On social media, posts are spreading, claiming to rank the boosters.
To verify, our team reached out to a pair of medical experts, Dr. William Schaffner from Vanderbilt University and Dr. Amesh Adalja from Johns Hopkins University.
We also tracked down the data, behind this social media graphic. The data comes from an NIH study that evaluated 458 individuals, split into nine groups. Each group represented a combination of one of the three vaccines, and one of the three boosters.
The numbers reflected in the social media graphic, show the "Geometric Mean Fold Rise" calculated through the study.
"Geometric fold rise refers to the level of antibodies that are measured after you get a vaccine," Dr. Adalja said. "So anytime you boost, you're going to get a rise in antibody. They're going to rise two-fold, three-fold, or whatever it might be."
The data indicated that there was a much bigger antibody response for mRNA boosters. This was especially the case for those who received the Johnson and Johnson vaccine as their initial dose, who saw the following antibody jumps in the study:
- 4.6X antibody increase after Johnson and Johnson booster
- 32.8X antibody increase after Pfizer booster
- 56.1X antibody increase after Moderna booster
"Clearly J and J followed by one of the mRNA vaccines gives you a higher antibody level than if it were followed by J and J itself," Dr. Schaffner said.
The data showed that mRNA boosters were preferable for those who received an mRNA vaccine as well. Due to the limited data, Adalja recommended people stick to the mRNA vaccine they received for the initial doses.
"If someone got the Moderna or Pfizer vaccine," he said. "I think they should stick with what they got. There's not really any benefit to switching within the mRNA vaccine class."
The data does have limitations, as noted by the study itself.
"Our study has limitations," it reads. "It was not designed to directly compare responses between different booster regimens. The sample size is insufficient for inter-group comparisons, and the demographics of those studied are not representative of the US population."
Adalja also noted that antibodies are not the only way to measure immunity.
"You have to remember that the immune system is more than just antibodies," he said. "It also includes T Cells and T Cell immunity, which isn't easy to measure. So you're only seeing one side of it."