Canada could be on cusp of fourth wave of Covid-19: Health authorities
Canadian health authorities have warned the country could be on the cusp of a fourth wave of the Covid-19 pandemic, driven by the Delta variant.
Canada’s chief public health officer Dr Theresa Tam said that their latest modelling, which was released on Friday, “suggests that we are the start of a Delta-driven fourth wave”.
Canada recorded 462 new cases of Covid-19 infections on Friday, an increase of over two-third over the numbers recorded two weeks earlier.
Tam cautioned that the country was in a “precarious period”, having to maintain the fine balance between vaccination levels and reopening.
Overall, 81% of the eligible population in the country has received one dose of a vaccine, while 66% are fully jabbed. But the more transmissible Delta variant means that those numbers may have to climb further to avoid the fourth wave.
Cumulative cases could reach 1,441,610 on August 8, from the current 1,430,046, according to the modelling. The modelling document stated Delta is the “most transmissible variant to date” and Canada has recorded a five-fold increase in proportion of Delta cases in June.
It also stated that the majority of Delta cases in Canada were in unvaccinated or partially vaccinated people and two vaccine doses were “needed for strong protection against variants of concern”.
That is also borne out by the infection trend data: 89.7% of new cases were reported in the unvaccinated population, just 0.5% in those fully vaccinated, and 4.6% in those partially vaccinated, and 5.3% in those not yet protected, meaning they had yet to complete 14 days since getting inoculated. Similarly, those unvaccinated accounted for 84.9% of hospitalisations as against just 0.7% for the fully vaccinated.
With several provinces shedding Covid-19 restrictions, there is concern reopening too hastily could result in a sharp spike by September, precipitating the fourth wave. The document noted, “The longer term forecast predicts stronger resurgence if community-wide contact rates increase too quickly, highlighting the need for ongoing caution.”
In recent weeks, Delta has displaced Alpha as the principal variant of concern causing new cases. According to official data, for the week ending July 4, Delta accounted for 76.5% of variant-driven cases, a figure that has been rising gradually.
The document released on Friday also underscored the reality related to the Delta variant, that there was reduced effectiveness against symptomatic infection after one dose, though there was only a “small reduction” after both.