“Although a lot of the debate right now is around the fourth dose, to me scientifically the clearest opportunity, what we have to do – and it’s not a matter of availability, the vaccine is available to us – is this third dose.”  Dr Fahad Razak told CP24 on Monday.
His comments come as opposition parties in Ontario are calling for fourth installments to be extended to the province, as Quebec has now done, in the face of a possible wave of declines.
Third doses are currently recommended in Ontario for all people aged 12 and over, while fourth doses are offered to people aged 60 and over, as well as people over 18 who are First Nation, Inuit or Métis.
But according to the latest vaccination data released by the province, just 57 percent of those 12 and older have received a third dose, despite widespread availability in the province.
“This third dose, this is the dose that clearly gives you increased protection not only from infection, but from serious illness.  And serious illness is what we are most interested in,” Razak said.  “So there’s a large number of people in Ontario right now who are eligible for that third installment who haven’t received it.”
Ontario began rolling out third installments in November and expanded eligibility to anyone 18 and older in late December.  However, the third tranche was disappointing and Ontarians were slow to catch on. 
While some people have said they don’t want to take more than the first two doses they were originally prescribed, Razak said advice on the number of shots needed has changed as the pandemic has progressed and the virus has changed.
“The virus has proven to be a really formidable opponent for us,” Razak said.  “And it’s mutated to the point that what’s now circulating in Ontario, Canada and the world is almost unrecognizable compared to what we originally saw and what we developed vaccines for.
“And so these increasing rounds of vaccination come out because we’re doing our best to protect ourselves from a mutated virus.”
However, he added that newer vaccines show promise in providing better protection against the latest strains of the virus.
“What will happen in the future is really unclear.  “One of the things that is very promising is vaccines that are adapted and developed against what’s out there now, as opposed to what was around two years ago when the virus first emerged from China,” Razak said.  “And so there is hope that these newer generations of vaccines will give us more durable protection.”
He said that in the meantime, and especially toward the fall, when other respiratory illnesses will be circulating, it makes sense to get any shots you’re eligible for and continue to be careful about coverage in high-risk settings to avoid infection.