Quebec is shortening the minimum time between first and second doses of the Oxford-AstraZeneca COVID-19 vaccine to eight weeks, Health Minister Christian Dube announced Thursday.
Second doses of the vaccine will start being administered at walk-in clinics on Saturday to people who received their first dose before April 3, Dube told reporters in Quebec City. People who received their first dose after April 3 will be able to receive a second dose in early June, Dube said.
Quebec had set 16 weeks as the period between first and second doses for all COVID-19 vaccines authorized in Canada.
The Health Department said the decision to shorten the wait for AstraZeneca is based on advice from the province’s immunization committee. It added, however, that a clinical trial has shown the vaccine is most effective if first and second doses are spaced 12 weeks apart.
“The best advice is, if you want to wait for the full 12 weeks, you can do that,” Dube said. However, the minister said the difference in effectiveness is “marginal” and that the shorter wait is intended for people who want to get fully vaccinated sooner.
Quebec currently has almost 150,000 doses of the AstraZeneca vaccine in stock. The province stopped administering first doses of that vaccine on May 13 over concerns about rare cases of blood clots. It also has not offered the vaccine to people under 45.
While the government recommends that people who received AstraZeneca get a second dose of the same, it will allow people to opt for a different vaccine for their second shot, but they will have to wait longer between doses.
Dube said Quebec will announce a plan next week to accelerate the administration of second doses of other vaccines.
According to Quebec’s public health institute, 57.1 per cent of residents have received at least one vaccine shot, while 5.9 per cent have received two doses or are considered adequately vaccinated after having tested positive for COVID-19 and received one dose. Authorities said 86,453 doses of vaccine were administered Wednesday, for a total of 5,202,132.
Meanwhile, Quebec’s blood bank said Thursday that a study of blood donors suggests that 10 per cent of Quebecers had developed antibodies to COVID-19 as a result of infection by the end of the pandemic’s second wave in March. Hema-Quebec said in a release that its study of blood donors shows the need for vaccination, because only a small percentage of the population has a level of immunity to COVID-19.
Quebec reported 436 new cases of COVID-19 Thursday and 10 additional deaths, including one within the previous 24 hours. The Health Department said the number of hospitalizations declined by five from the day before, to 394 and 96 people are in intensive care, a decline of five.