COLORADO, USA — Clinical trials in the United Kingdom are currently underway to study the efficacy effects of mixing two different COVID-19 vaccines, according to CNBC.
While the CDC stated it is OK to mix Pfizer and Moderna shots in certain situations, they have yet to study if the two different vaccines would change the safety or effectiveness.
"So I sat there, gave my card to the vaccination, and said, 'OK, I'm getting my second dose of Pfizer'," said Lilly, a Coloradan who got mix-match doses.
She received her first dose of Pfizer on March 18 at a Safeway in Littleton, but before it was time for her second dose, she got an email from her job that said she qualified for a Safeway vaccine drive at her work so she jumped on it.
"I go to my next table to get my little sticker on my vaccination card, and the lady says, 'Ok, we're putting the Moderna down,' and I said 'no, I think there's an error here.'"
Despite telling her vaccine provider several times, Lilly said she was still given the Moderna vaccine rather than Pfizer. While the vaccine providers on-site could not tell her the ramifications, she said they did file an incident report.
Lilly said she hoped in the future, additional information could be made available so that vaccine providers would know what to say or do if they administered mix-match doses.
9Health expert Dr. Payal Kohli said while the research on efficacy is still underway, Lilly and others like her shouldn't be concerned.
"Don't panic; it's likely safe, and it's likely effective," Kohli said. "In fact, some potential scientific research from the lab tells us it may actually be advantageous to the immune system. It may boost the immune system response even more to match different types of vaccines."
The Colorado Department of Public and Environment stated they monitor anything out of the ordinary. If a Coloradan has a peculiar experience, they encourage them to report it.
Safeway said they monitor all vaccinations and coach and train their pharmacy teams. They added that they follow the CDC guidelines and if someone does get a mix-match dose or Pfizer and Moderna, they are considered fully vaccinated.
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