According to the Ministry of Health, all the local and imported cases of Covid-19 in April (those that underwent genome-wide sequencing) were found to be the Omicron variants.
MOH said on 19 May that 99% of the local cases were the BA.2 strains, including the BA.2.12.1; while the remaining 1% were the BA.1 sub-variant.
98% of the imported cases were from the BA.2 sub-variants, 1% being the BA.1 sub-variants and the other 1% being the recombinant lineages including the XJ and XE strains, which are hybrids of the BA.1 and BA.2 sub-variants.
Two of the imported cases were infected with the BA.4 strain, and MOH also detected two local cases on 15 May with the BA.4 sub-variant, and one case of the BA.5 sub-variant (local).
All three of the cases are confirmed to be the BA.4 and BA.5 sub-variants, which has been described as a variant of concern by the European Centre for Disease Prevention and Control.
MOH also reported 4,578 new cases on Thursday, a reduction from 6,442 cases on Wednesday.
Hospitalisations remained at 302, with 8 patients in the ICU and 49 needing oxygen supplementation, along with 2 deaths.
The week on week infection rate also rose to 1.14, up from 1.05 from a day before.