Researchers in Belgium directly compared the Pfizer and Moderna COVID-19 vaccines by testing the antibodies of 2,500 health care workers after two doses of both vaccines.
The study found the Moderna vaccine produced more than double the antibodies compared to Pfizer, but doctors urge caution.
“Antibody level itself is interesting, but it doesn’t necessarily lead to a significant difference in the way the vaccine is performing,” said Dr. Allison Arwady, Commissioner of the Chicago Department of Public Health.
Chicago is tracking breakthrough infections by vaccine, but Arwady said they haven’t found a substantial pattern.
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“We have seen the highest number of breakthrough infections in Chicagoans who have gotten Pfizer, but that is because the highest number of Chicagoans have gotten Pfizer, not that we’ve seen a major difference in someone who’s gotten Pfizer versus Moderna,” Arwady said.
When NBC 5 asked the Illinois Department of Public Health for a breakthrough breakdown, spokesperson Melaney Arnold said that “all three vaccines have been reported in breakthrough hospitalizations and deaths. Similar to the CDC, IDPH is not currently reporting that breakdown.”
Another study to consider when comparing vaccines is one from the Mayo Clinic earlier this month. After looking at data from 50,000 patients, researchers said the Moderna vaccine may be more effective against the Delta variant than Pfizer.
With booster shots expected to begin rolling out next month, NBC 5 asked Dr. Richard Novak, Head of the Division of Infectious Diseases at University of Illinois Health, if Pfizer patients should be lining up first?
“Based on what limited information we have, giving the boosters and targeting the higher risk groups first, makes sense. Whether or not people who got Pfizer vs. Moderna need to worry more, we just don't have enough information yet to say that," Novak said.
Early guidance stills stands and the CDC recommends you complete a full course of the same vaccine and not to mix coronavirus vaccines.