For the first time in Maharashtra, four patients of B.A.4 sub-lineage and three cases of B.A.5 sub-lineage of the Omicron variant of coronavirus have been found, the state health department said on Saturday.

These were mild sub-lineages and there was no cause for concern, a senior health official said.

The sub-lineages of Omicron were found in April in some parts of the world including South Africa. Last week, cases were also reported in Tamil Nadu and Telangana in India.

The whole genome sequencing was conducted by the Institute of Science Education and Research, and its finding has been confirmed by the Indian Biological Data Centre in Faridabad. As many as seven patients, all from Pune, were detected with the infection of the sub-lineage of Omicron, a health department official said.

Four patients have the infection of B.A. 4 variant while others have contracted the B.A. 5. Four of them are men and three women. Four patients are above 50 years of age while two are in 20-40 age group while one patient is a nine-year-old child, he added.

All the six adults have completed both the dosages of vaccine while one has taken the booster shot too. The child is unvaccinated. All of them had mild symptoms of COVID-19 and were treated successfully in home isolation, the official said.

Their samples were taken between May 4 and 18. Two of them had travelled to South Africa and Belgium, while three had travelled to Kerala and Karnataka. The other two patients had no recent travel history, he said.

Dr Pradeep Awate, epidemiologist and the State Surveillance Officer, Integrated Disease Surveillance Programme, said that B.A. 4 and B.A. 5 are sub-lineages of Omicron which itself is known for being mild.

Hence, "there is nothing to worry about its sub-lineages, he said.

However, it is highly transmissible, which is one of the reasons behind the growing number of COVID-19 cases in the last couple of weeks. The cases are steadily going up everywhere, but patients are not being hospitalised in large numbers, Awate added.

There is no severity found in the infection of these Omicron sub-lineages. But state officials are closely watching the situation, he said.

On May 22, a B.A.4. case was found in Tamil Nadu while a B.A.5 infection was reported in Telangana.