How long a gap you had between your first and second dose of an mRNA COVID-19 vaccine (Pfizer or Moderna) affects how strong your COVID-19 immunity is, according to researchers at the University of British Columbia.
“We found significantly higher levels of antibodies in individuals who had longer vaccine intervals, and this was consistent regardless of which mRNA vaccine was administered,” says Dr. Brian Grunau in a press release.
The peer-reviewed study, published Nov. 30, involved 186 paramedics. It's the first in North America to study immune system strength and dose gap.
Because of their job, some paramedics got both doses in less than four weeks, as was recommended early on in the vaccine rollout. Another group, who were vaccinated six or seven weeks apart, were also tested. The second group had a heightened level of antibodies, researchers found.
While not the only way to measure a body's response to a vaccine, antibodies are a significant metric for immune strength.
Grunau, the study's lead, says this will allow health authorities to strategize their continued vaccination plans. While the vast majority of people in Vancouver are vaccinated, half the world's population has yet to receive vaccines, says UBC.
“This longer interval strategy enables early access to first doses in the population and ensuring the best protection possible with the two-dose series,” adds Grunau.
The study is part of a larger effort by Canadian researchers in B.C. and Ontario to understand the impact of the pandemic on paramedics.