Noting that the world is witnessing a fourth surge in Covid -19 cases, the government on Friday cautioned people against lowering the guard, particulary during year-end festivities.

It urged people to avoid crowding and unnecessary travel and stressed on COVID-19-appropriate behaviour and expedited vaccination.

Addressing a joint press conference on the pandemic, a senior official said the predominant strain in India continued to be Delta, including in recently identified clusters.

India has so far reported 358 cases of the Omicron variant, of which 183 were analysed and 121 of them were found to have foreign travel history.

Of the 183 Omicron cases analysed so far, 91 per cent were fully vaccinated with three having booster shots, 70 per cent were asymptomatic, and 61 per cent were males, the government said.

Citing the World Health Organisation's findings, the government said omicron has significant growth advantage over Delta and is spreading fast through communities with a doubling time of 1.5 to 3 days.

The world is witnessing a fourth surge in Covid -19 cases and having an overall positivity rate of 6.1 per cent.

The government said the COVID-19 case positivity rate in Kerala and Mizoram is much higher than national average and a cause for concern.

It said 20 districts across country were reporting a weekly positivity rate between 5 and 10 per cent and two districts over 10 per cent.

The government cautioned people against lowering the guard, particulary during Christmas and New Year festivities.

It said about 61 per cent of India's adults are fully vaccinated against COVID-19 and 89 per cent have been administered the first dose.

In view of the emergence of the Omicron variant, the government appealed to the private health sector to be ready as it has to play an important role in managing the pandemic.

According the Union Health Ministry data updated at 8 am, India recorded 6,650 new coronavirus infections, taking its tally of cases to 3,47,72,626, while the count of active cases has declined to 77,516.

The death toll due to the disease has climbed to 4,79,133, with 374 daily fatalities being recorded.