Doctors say lowering age cutoff for AstraZeneca vaccine makes sense as cases surge

Doctors say the Oxford-AstraZeneca vaccine should be offered to Canadians in a wider age range as COVID-19 infections soar in many parts of the country.

Provinces limited eligibility for that vaccine to those 55 and older after a small number of cases of an unusual and serious blood-clotting condition appeared in younger people — mostly women — who had received a shot.

The odds of someone getting the syndrome — dubbed vaccine-induced immune thrombotic thrombocytopenia — has been estimated at between one in 100,000 and one in 250,000.

By comparison, about one in four people hospitalized with COVID-19 will experience a blood clot, Alberta's chief medical officer of health Dr. Deena Hinshaw noted this week.

Risk assessment 

"Certainly based on risks, most people are much better off with a vaccine," said Dr. Daniel Gregson, an associate professor at the University of Calgary's Cumming School of Medicine.

"You can certainly drop it easily to 45, if not 35."

Gregson, who specializes in infectious diseases and medical microbiology, said uncertainty has been planted in peoples' minds about getting AstraZeneca, but they do things that are just as risky on a daily basis without a second thought.

Dr. Susy Hota, medical director of infection prevention and control at Toronto's University Health Network, said she would also support dropping the age limit, so long as no other worrying side-effects arise and recipients are aware of the risk, however small.

"I think it's an important strategy we need to consider," said Hota, also an associate professor of infectious diseases at the University of Toronto.

"The case counts are going up too fast and they're going to a point where it's hitting the hospitals in a way that we've not experienced before, ever."

Hota suggested one approach could be offering the shot to younger men, since the rare side-effect seems to be more prevalent in women.

Health Canada has deemed the AstraZeneca vaccine safe, saying the benefits outweigh the risks.

The National Advisory Committee on Immunization has not yet changed its recommendation that the shot only be offered to those 55 and up, but the decision ultimately rests with provinces.

Alberta, Quebec may expand access

In Quebec, where AstraZeneca is available to those between the ages of 55 and 79, Health Minister Christian Dube said provincial public health authorities were considering whether to expand access.

Alberta is also considering a change, Hinshaw said.

"I also know that some who are younger than 55 are interested in getting the protection that this vaccine offers," she said Thursday.

"Given the Health Canada assessment, we will be discussing this question with our Alberta Advisory Committee on Immunization this week to get their perspective."

In the meantime, Hinshaw is urging anyone who is already eligible to get their AstraZeneca dose without delay.

Walk-in vaccinations are available at 26 pharmacies in Calgary and Edmonton and Alberta Health Services is opening walk-in vaccination clinics this weekend in both cities.

"While not getting vaccinated may feel like a way to protect your health by avoiding the rare risk of a blood clot following vaccine, waiting can actually increase your risk of getting sick, or worse," Hinshaw said.