The tally of the Omicron variant of the coronavirus disease on Sunday rose to 21 after seven new cases were detected in Maharashtra, one in Delhi and nine in Rajasthan, India Today reported.

In Delhi, a traveller, who had returned from Tanzania, tested positive for the infection, ANI reported.

The patient has been admitted to the city’s Lok Nayak Hospital, Delhi Health Minister Satyendar Jain said.

“Samples of 12 out of 17 positive passengers were sent for genome sequencing and one of them, who arrived from Tanzania, tested Omicron positive according to preliminary report,” Jain said.

The patient in Delhi has mild symptoms, an unidentified official told PTI. The official added that the person’s travel history is being collected and contacts are being traced.

In Maharashtra, the samples that were found positive for the Omicron variant belong to a 44-year-old woman, who had travelled from Nigeria, her two daughters, her brother and her two nieces, a statement from the state health department said.

A 47-year-old man, who travelled from Finland in November, was also found positive, the Maharashtra government said.

The 44-year-old woman, who is a citizen of Nigeria, was visiting Maharashtra’s Pimpri-Chinchwad city to meet her brother, a state health official said.

Thirteen contacts of the woman were traced and their samples were sent for testing after which her brothers and his two daughters were found positive for the Omicron variant.

The woman has mild symptoms while the others are asymptomatic. Three of them were vaccinated – two of them were administered Covishield and one Covaxin. The remaining three are not adults and not inoculated, the statement said.

The state government said that all of them have been admitted to Jijamata Hospital in Pimpri-Chinchwad and their health condition is stable.

The presence of the Omicron variant in the 47-year-old man in Pune was detected through routine surveillance, the statement said. He had visited Finland between November 18 and November 25.

The man was tested after he suffered mild fever and was found positive. He is fully vaccinated with the Covishield vaccine. His health condition is stable and is without any symptoms.

In Rajasthan, the cases were found in a family of nine who had travelled from South Africa. The state health department said that samples of 35 people, including the family and others who came in contact with them.

The health department has isolated the remaining 25 people who tested negative for the infection.

India’s first two cases of the Omicron variant had been detected in Karnataka on Friday. After that, one case each was reported from Gujarat and Maharashtra.

The Omicron variant was first detected in South Africa in November and has spread to many other countries. Scientists are studying if the variant is more infectious than Delta or has the potential to evade vaccines.

According to the World Health Organization, the Omicron variant has about 45-52 mutations with 26-32 mutations in spike proteins. Spike proteins help a virus gain entry into the host cell. So, the higher number of mutations of the Omicron variant help the virus in a faster entry into human cells.

States in India have stepped up measures to screen travellers coming in from South Africa, the United Kingdom, Brazil, Botswana, China, Mauritius, New Zealand, Zimbabwe, Singapore, Hong Kong and Israel. They are being tested at airports and asked to quarantine.