XE, XD & XF: what to know about the Omicron hybrid variants
Canada recently reported its first cases of the Omicron subvariant XE, one of several hybrid variants of SARS-CoV-2 that have emerged since the beginning of this year. First detected in the United Kingdom in January, XE has genetic material from the Omicron subvariants BA.1 and BA.2, along with