It comes as another 11 people have died with Covid-19 and another 8150 new community cases have been detected.
The subvariant was detected in the Hawke's Bay from a test returned on 10 May.
"This Omicron subvariant is prevalent in the USA and has been detected at our border for many weeks - there have been 29 imported cases reported since April, so its movement into the community is not unexpected," the ministry said.