The credibility of Health experts and their advice took another hit with news that the World Health Organization‘s chief scientist on Monday advised against people mixing and matching COVID-19 vaccines – something Canadian health experts have been recommending for more than a month. Canada, which has been mixing and matching Health Canada approved vaccines since June.
“It’s a little bit of a dangerous trend here. We are in a data-free, evidence-free zone as far as mix and match,” WHO’s Soumya Swaminathan told an online briefing.
At the time, the National Advisory Committee on Immunization (NACI) said people who received a first dose of the AstraZeneca vaccine should get an mRNA vaccine — Pfizer-BioNTech or Moderna — for their second dose, unless contraindicated. The vaccines can safely mixed and matched in most scenarios, they said.
Mixing vaccines ramped up in late June in Ontario, when officials promoted the use of Moderna’s vaccine for second doses due to a shortage of Pfizer-BioNTech in the province. Other provinces also took on the recommendation. One could almost detect a note of irritation in a tweet from Ontario health officials as they essentially dismissed the WHO advice.
With over 70 percent of Ontarians having received one shot and half of the province fully vaccinated, the WHO message comes a bit late to have any material effect.