Front Burner

COVID's latest subvariants: What you need to know

Omicron subvariants BA.4 and BA.5 have become the dominant strains of COVID-19 in the U.S. How worried should we be about them in Canada?
A nurse wearing blue gloves handles a COVID-19 test swab.
A nurse gets a swab ready at a temporary COVID-19 test clinic in Montreal in May 2020. According to experts, the BA.4 Omicron subvariant appears to be more transmissible than previous COVID-19 variants, but does not appear to cause more severe illness. (Paul Chiasson/The Canadian Press)

The Omicron subvariants BA.4 and BA.5 are spreading quickly. They already make up a majority of new COVID infections in the U.S., and it appears they are much better at getting around immunity. Research from Harvard Medical School show that BA.5 "may escape antibody responses."

The spread of these subvariants has coincided with the lifting of mask mandates and the relaxing of many public health measures nationwide.

To provide you with details about the latest COVID-19 variants and the state of the pandemic here in Canada heading into the summer, we are joined once again by Dr. Zain Chagla, an infectious diseases physician at St. Joseph's Healthcare in Hamilton.

 

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