The fast-spreading Omicron subvariants BA.4 and BA.5 may soon be dominant in Thailand.

According to Thailand's Medical Science Department director-general Dr Supakit Sirilak, the Omicron variants accounted for 100 percent of new Covid-19 cases last week, and 50 percent of the Omicron variants comprise the BA.4 and BA.5 subvariants...