VADODARA: A 29-year-old NRI who recently came to Vadodara in Gujarat from South Africa has been found infected with the BA.5 sub-variant of the highly-transmittable Omicron variant of coronavirus, a health official said on Tuesday.

The man, who lives in South Africa, had on May 1 tested positive for the coronavirus after he arrived here to meet his parents.

He had left for New Zealand on May 10 after testing negative for the virus, Vadodara Municipal Corporation's chief health officer Dr Devesh Patel said.

His sample was sent to a laboratory in Gandhinagar for genome sequence.

The report, received on Tuesday, confirmed that he was infected with the BA.5 sub-variant of the Omicron variant of coronavirus, he said.

"After testing positive for the coronavirus on May 1, the man was under self-isolation. He tested negative before leaving for New Zealand on May 10. His current whereabouts are not known," Dr Patel said.

"The patient showed no symptoms. His parents, who were his only contacts, had tested negative for COVID-19 at that time. They have again tested negative for the virus," the official said.

The Indian SARS-CoV-2 Genomics Consortium (INSACOG) had on Sunday confirmed the presence of the BA.4 and BA.5 Omicron sub-variants of the coronavirus in India- one case in Tamil Nadu and another in Telangana.

BA.4 and BA.5 are sub-variants of the highly-transmissible Omicron variant circulating globally.

These were first reported from South Africa earlier this year and are now being reported from several other countries.

The INSACOG had said these sub-variants have not been associated with disease severity or increased hospitalisation.