The Middlesex-London Health Unit (MLHU) is extending the maximum wait time for those receiving the two-dose Pfizer-BioNTech COVID-19 vaccine in an effort to dole out more shots to local residents.
Pfizer’s vaccine requires recipients to take two doses at separate times, with the shot originally authorized to be scheduled 21 days apart.
On Tuesday, the MLHU announced it would be extending the maximum time between doses for local residents to 112 days, or 16 weeks.
The move was made under the direction of Ontario’s chief medical officer of health Dr. David Williams, according to the MLHU.
“In a memo sent to all Medical Officers of Health, Dr. David Williams indicated that extending the time between doses would increase the number of individuals benefiting from a first dose of vaccine in the context of a limited COVID-19 vaccine supply,” said the MLHU in a release attached to Tuesday’s announcement.
“The recommendations were also in line with recommendations from the National Advisory Commitee on Immunization (NACI).”
The change will force the rescheduling of most second dose appointments for those who already received their first dose at either the Western Fair District Agriplex or the Mount Brydges COVID-19 vaccination clinics.
This includes second dose appointments that were scheduled to happen Wednesday. The rescheduling should affect about 10,000 people, according to the MLHU.
Long-term care and retirement home residents whose second dose appointments were scheduled to take place on or after Wednesday will not have to face rescheduling.
Anyone who is subject to rescheduling will be notified by text message or email, depending on how they booked their first appointment.
The Ontario government’s decision to extend the time between COVID-19 doses prompted a joint letter from a number of senior Canadian scientists that raised a number of concerns.
A draft of the letter obtained by Global News from an Ontario government source highlighted the unknowns surrounding the plan and the thoroughness of it.
The draft raised significant worries about variant spread and the effect a delayed second dose could have. It also urged governments to identify priority populations to receive second doses sooner.
The document was signed by doctors with the University of Toronto, University Health Network (UHN), Sunnybrook Research Institute, Princess Margaret Cancer Centre and Montreal Clinical Research Institute.
According to sources, the letter was sent to Canada’s Chief Public Health Officer Dr. Theresa Tam, as well the governments of Ontario, Alberta and British Columbia — all of which have indicated they are planning on implementing the four-month delay.
MLHU’s medical officer of health Dr. Chris Mackie told Global News that while he understands the concerns in the joint letter, he says there is “growing data that the first dose gives good protection, but it’s not perfect data.”
“What’s happening here is you’re really making a judgment call, not at the individual level but at the population level, that this is the best way to protect as many of our population as possible,” Mackie said.
“It’s not ideal … but we don’t have all the vaccine in the world and hard decisions do need to be made and I think this is one that actually has a lot of scientific and public health science behind it.”
While the letter urges governments to identify priority populations to receive their second shots sooner, Mackie notes that the local change will not affect long-term care and retirement home residents.
“The people that we know are most vulnerable, those that live in long-term care and retirement homes, that’s been about two-thirds of the deaths in Ontario and locally as well,” Mackie said.
“Those folks will not have their second doses delayed.”
As of Monday, more than 44,000 vaccine doses have been doled out to residents attending vaccination clinics in London and Mount Brydges.
Vaccine appointments remain available for certain high-priority health-care workers, Indigenous folks 55 and older and anyone else who is 80 or older. However, the MLHU clarified on Monday that the 80 or older criteria applies for anyone born in 1941.
A full list of who’s eligible for a vaccine can be found here.
Appointments can be booked online at www.covidvaccinelm.ca or over the phone at 226-289-3560. The phone lines are open between 8 p.m. and 5:30 p.m. for seven days a week.
—With files from Travis Dhanraj and Nick Westoll
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