Most Omicron cases so far vaxxed, but data too little

State authorities say cohort is still too small to conclude the behaviour of the highly mutated virus

MUMBAI: More than 80% of the Omicron cases detected in the state since December 4 are breakthrough infections- that is among people who are fully vaccinated.

State health authorities said that the Omicron cohort is still too small to conclude the behaviour of the highly mutated virus, but preliminary observations highlight its immune escaping nature which should be considered as a point of caution. Of the 54 Omicron cases detected in Maharashtra till December 19, 44 are among fully vaccinated people. Among the remaining 10 cases, two people were unvaccinated but one of them had contracted Covid-19 in the past, and eight were minors and thus not eligible for the jabs.

“As seen globally, the new variant does evade immunity developed through vaccination or previous infection,” said Maharashtra surveillance officer Dr Pradeep Awate. “But we cannot ignore the fact that all the patients had a mild and asymptomatic infection and the vaccination has an important role in this,” he said.

A majority of people in Maharashtra and the rest of the country have received the Oxford University and Astrazeneca’s vaccine-covishield. In comparison, a small percentage of the population has received Covaxin developed by Indian company Bharat Biotech. Preliminary studies have shown Omicron’s ability to evade through the immunity developed by most of the widely used vaccines. Newly published observations by researchers at Cambridge University pointed that the new mutant could cheat existing immunity but it could not cause replication of cells, which is perhaps why it causes a milder disease.

“Little is known about whether the mild disease caused by Omicron is due to the virus’ inherent nature or because of the vaccination,” said infectious disease expert Dr Tanu Singhal. “Some studies have shown that a previous Covid-19 infection offered 80% protection against the Delta variant, but it offers only 20% protection against Omicron. It is therefore clear that we will see a rise in cases by January-february. Our health systems should be prepared as given our population, the magnitude of the cases could be high,” she said.

Health experts said that data on how the virus will behave in senior citizens is not available currently,