New Omicron COVID subvariant, BA.4 or BA.5, found in Australia in Melbourne wastewater.

Both BA.4 and BA.5 are sister variants of the original BA.1Omicron variant.

As of March, the BA.4 subvariant had been detected in South Africa, Botswana, Denmark, and the United Kingdom.

While BA.5 cases have been primarily detected in South Africa, with a single case in Hong Kong.

Both the BA.4 and BA.5 strains are still rare. 

The new subvariant has only been detected in a handful of countries worldwide. 

As per WHO, less than 200 sequences of the new strains had been collected.

This subvariant has been recently detected in a small number of cases in ......

South Africa, Botswana, Belgium, Denmark, the United Kingdom and Germany. 

The WHO is already monitoring BA.1 and BA.2 subvariants, as well as BA1.1 and BA.3.

Previously, XE was the latest discovered mutant of Covid-19., found in United Kingdom.

'XE', is a mutant hybrid of two variants of Omicron - BA.1 and BA.2.