Alarmed over the possibility of an increase in transmissibility of the Delta variant of Covid-19, Canadian health authorities are calling for acceleration of administration of second doses of vaccines, particularly to those in communities considered most at risk.
“The Delta variant or B.1.617 has been detected essentially across Canada,” Canada’s chief public health officer Dr Theresa Tam said on Friday, according to the agency Canadian Press.
The Public Health Agency of Canada or PHAC believes the variant, which was first detected in India, is “at least 50% more transmissible” than the original coronavirus which originated in China, according to a statement released by Tam on Thursday.
And, it also stated that the four major variants of concern “all have certain mutations in common, which may have an impact on vaccine effectiveness, although the evidence is still limited”.
Therefore, Tam stressed on Friday it “is very important to get that second dose when variants” like Delta were present in the country.
Surprisingly, despite being declared a variant of concern or VoC in mid-May, PHAC is yet to release any data on the extent of the spread of the B.1.617 variant in Canada, while it provides daily updates on the Alpha, Beta and Gamma variants.
However, Tam said that in the “context of a transmissible variant, that variant could well takeoff and replace other viruses in the communities”.
That alert was sounded earlier this week by Dr Lawrence Loh, medical officer of health in the Peel Region of Ontario, as he said during a press interaction: “B.1.617 is quickly replacing B.1.1.7, which was the Alpha variant originally detected in the UK and which drove our third wave across Brampton and the region of Peel.”
He warned the Delta variant could become the dominant strain in the region in a month and then across the province in a matter of weeks after that. Peel region comprises cities in the suburbs of Toronto and is among the most densely populated areas in the country.
While less than seven per cent of Canadian have been fully vaccinated, Mayors within the Peel Region have called for quickening that pace because of the threat that the Delta variant could precipitate another wave of the pandemic even as the country is slowly emerging from a third wave.
The National Advisory Committee on Immunisation or NACI’s guidelines state that second doses can be given up to four months after the first, but in an updated recommendation on May 28, it said “second doses should be offered as soon as possible, with priority given to those at highest risk of severe illness and death from COVID-19 disease after or concurrent with first doses for all remaining eligible populations.”