Ontario suspends use of one of its vaccines
Vaccinated people are increasingly being diagnosed with severe side effects.
On May 11, Ontario Ministry of Health Chief Medical Officer Dr. David Williams announced that the province will no longer use AstraZeneca as the first dose of the drug. Ontario was one of the provinces that reduced the age threshold for vaccination with the drug to 40 years old.
The reason for this decision was an increase in cases of severe complications: a rare type of thrombosis called VITT — vaccine-induced immune thrombocytopenia — was detected in those vaccinated.
As of May 8, the statistics in the province were as follows:
- 615,000 doses of AstraZeneca were administered, with a VITT rate of 0.9 per 100,000 vaccinated;
- 202,800 doses of SOVISHIELD vaccine were administered, the VITT rate being 1 case per 100,000 vaccinated.
COVISHIELD is a vaccine produced by the Serum Institute of India in collaboration with AstraZeneca.
However, in recent days, the number of VITT cases has risen to 1.7 per 100,000 doses administered.
The Ontario government is now working with the Public Health Agency, the Scientific Advisory Board and federal agencies to consider using AstraZeneca as a second dose for people who have been vaccinated with another drug, such as Pfizer or Moderna. All of these vaccines require twice-daily administration.
According to Williams, evidence from the UK suggests that the risk of developing VITT is significantly reduced when AstraZeneca is used as a second dose. He noted that there are already initial results from administering two doses of different vaccines, and they are "promising".
Williams also stressed that those who have already been vaccinated by AstraZeneca have done absolutely the right thing. The daily number of cases in the province has gone down, but is still high. During May 10, there were 2,073 cases of infection and 15 deaths.
The controversy surrounding AstraZeneca has been ongoing since March, when several European countries rejected the drug due to side effects. In April, Canada recorded the first death from the vaccine. Now, AstraZeneca can be used for people 30 years of age and older, according to a recommendation from Canada's National Advisory Committee.
