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'the virus has become smarter'

people infected with the variants were, on average, younger, but still had higher risks of hospitalization and icu admissions.

covid variants causing more severe disease, canadian study shows
an icu team helping to intubate a patient suffering from covid-19 at humber river hospital in toronto. (photo by cole burston / afp)
by: sharon kirkey
a new canadian paper is sending out an unnerving message that may help nudge the vaccine hesitant: covid-19 variants not only spread more easily, they’re capable of causing more severe disease — the delta variant in particular.
the study, based on more than 212,000 cases of covid-19 logged in ontario between february and through to near the end of june, found higher risks of hospitalizations, admissions to intensive care and death with “variants of concerns,” or vocs, compared to the initial, wild-type strain.
with delta infections, the risk of hospitalization was 108 per cent higher, admission to icu was 235 per cent higher and death 133 per cent higher.
of the total cases studied, only 2.8 per cent were “probable” delta, which is now the dominant strain.

people infected with the variants, renamed in may after letters of the greek alphabet — alpha, beta, gamma and delta — were, on average, younger and less likely to have an underlying health conditions, “but nonetheless had higher crude risks of hospitalization and icu admissions,” the authors wrote in a study published tuesday by the canadian medical association journal.

given the relatively small number of delta infections in the study, “it is remarkable that we detected a clear and significant elevated risk of uncommon, delayed outcomes, such as death,” they wrote.

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the positive news: vaccines have “undoubtedly blunted” the impact of vocs, providing 80 to 90 per cent protection against dying of covid, even in cases of breakthrough infections.

“canada is battling a different pandemic from the one it faced in early 2020,” kirsten patrick, interim editor-in-chief of the cmaj, wrote in an accompanying article.

“the virus has become smarter and more dangerous, which means that we need to be smarter too.”
delta’s ability to cause more severe sickness and breakthrough infections in the fully vaccinated, as well as reports that vaccine-induced immunity may not last as long as originally thought, aren’t the only factors “dimming the light at the end of the pandemic tunnel,” patrick said. she also blamed a “perverse pandemic of misinformation” for stoking vaccine hesitancy, as well as outright refusal, jeopardizing efforts to reach herd immunity.
most people in critical care with covid-19 are unvaccinated.
epidemiologists david fisman and ashley tuite, of the university of toronto’s dalla lana school of public health, authored the cmaj paper.
the study bolsters studies from england, scotland and singapore that also found higher risks of bad outcomes with delta infections, with people more likely to need emergency care, oxygen therapy or admission to an icu.

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the ontario paper involved people who tested positive for sars-cov-2 and were screened for variants that carry a common mutation on a particular part of the spike protein that studs the outside of the virus. the mutation makes it easier for the virus to get inside human cells.
alberta and saskatchewan are facing higher-than-ever demands for critical care, patrick  wrote. leaders in both provinces “decided to disregard the cautions of scientists who warned of the dangers of vocs; instead, they preached hope by promising ‘the best summer ever.’”
the canadian medical association and canadian nurses association are holding an “emergency” covid summit tuesday night, a closed meeting, followed by a media debriefing wednesday, of some 30 national and provincial organizations.
“rising numbers of covid-19 cases have brought the health system to a breaking point in many parts of the country,” the cma said in a release. vaccination rates are stalling and health workers are “exhausted and demoralized.”

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