The Quebec government says fully vaccinated residents who have received the Oxford-AstraZeneca COVID-19 vaccine can receive a third dose of the mRNA vaccine prior to travel.
Quebec is offering the extra shot because some countries don’t recognize the version of the AstraZeneca vaccine made at the Serum Institute in India — known as COVISHIELD — and Canadians who have received the vaccine may find themselves denied entry.
Many European countries, for example, do not recognize this vaccine. The new EU vaccine passport counts only those approved by the European Medicines Agency, which does not list COVISHIELD.
There are also reports of several cruise lines accepting only certain vaccines or shot combinations, including Princess Cruise Lines, Which does not consider guests who received any copy of the AstraZeneca vaccine followed by the mRNA vaccine to be “fully vaccinated”. However, the company allows two different doses of the same type of vaccine even if they are made by different brands.
On Monday, Quebec officials indicated in a press release that the third doses will only be available to people who need to travel soon and for an essential reason.
The county said it would also press Ottawa to try to persuade other jurisdictions to accept the COVISHIELD and AstraZeneca vaccinations.
Quebec health officials caution that it is up to the recipient to seek advice and assess risks before receiving a third dose of the Pfizer-BioNTech or Moderna mRNA vaccines.
A spokesperson for the county health department said that the third dose does not necessarily provide greater protection compared to two doses, and that the safety of receiving two doses of AstraZeneca mixed with the mRNA vaccine is unclear.
Watch | What we know about mixing COVID-19 vaccines:
There are no studies evaluating the effect
Robert Maranda, of the Department of Health, says there are no studies evaluating the effect of receiving three doses of two separate vaccines.
“The person should be properly advised to be informed of the potential risks associated with this added dose compared to the benefits of the planned trip,” he said in an email.
“It is up to everyone to weigh the risks and benefits.”
These comments contradict advice from World Health Organization (WHO) officials who recently stressed that it should not be individual citizens who make the call about whether they will get additional shots.
“Individuals shouldn’t decide for themselves, public health agencies can, based on available data,” Dr Soumya Swaminathan, WHO’s chief scientist, said in a recent tweet to elaborate on broader comments she made about vaccine mixing during a briefing.
Watch | The NACI recommends that counties stop administering AstraZeneca in most cases:
No evidence a third dose is needed, says NACI
Currently in Canada, Guidance recommendations From the country’s National Immunization Advisory Committee (NACI) there is currently no evidence that booster doses of the COVID-19 vaccine are needed after the vaccine series has been completed.
However, the NACI recommends switching different vaccines at different doses in certain situations.
The advisory body advocates that the same mRNA vaccines be used for a second dose if possible, but another injection of mRNA “may be considered interchangeable” if the first type is not available.
The NACI also recommends that the AstraZeneca, COVISHIELD, or mRNA vaccine can be offered as a second dose to people who have received the first shot of AstraZeneca or COVISHIELD. He points out that mRNA options are indeed preferred as a second dose, thanks to emerging safety evidence and the potential for a better immune response.
Currently, vaccines Certified for use in Canada They include both versions of the AstraZeneca shot and those produced by Pfizer, Moderna and Johnson & Johnson.