After large waves of SARS-CoV-2 this summer, experts predict a relatively "quiet" fall.
Hybrid immunity from widespread infections and vaccination has transformed SARS-CoV-2 into a "manageable endemic respiratory virus," said Mel Kradjen of the B.C. Centre for Disease Control's public health laboratory in a seminar presented by Canada's COVID-19 immunity task force.
The next three months will "likely be quiet from a COVID perspective," although early winter "may be different" as immunity wanes again.
More than 60% of Canadians have infection-acquired antibodies, according to serology data presented by the immunity task force.
However, older people remain vulnerable and should receive additional immunizations, Kradjen said. While infections increased across all age groups during the Omicron era, just 40% of people over 60 have protective antibodies from infection versus 73% of younger people.
Hybrid immunity generates a strong immune response, but SARS-CoV-2 remains a very dangerous infection that can cause exacerbated inflammatory responses that can last for months, said Charu Kaushic, scientific director of the institute of infections and immunity at the Canadian Institutes for Health Research.
What does endemic mean?
While the "boat has sailed" on eliminating SARS-CoV-2, it's still unclear what kind of endemicity the virus will establish, said Kaushic.
Endemic means that a virus is continually present and somewhat predictable--not that it's harmless or that precautions to prevent infections are unnecessary.
"It frustrates me when policy-makers invoke the word endemic as an excuse to do little or nothing," wrote Aris Katzourakis in Nature earlier this...