Top scientists for COVID booster vaccine dose

New Delhi: A day after India reported its first two cases of the highly infectious Omicron, a consortium of 28 laboratories to monitor genomic variations in the virus recommended to the Centre that it consider a booster dose of Covid-19 vaccines for those above 40 years, with preference to high-risk and high-exposure population.

The recommendation has been made by top genomic scientists in the weekly bulletin of the Indian SARS-CoV-2 Genomics Sequencing Consortium (INSACOG), a network of national testing labs set up by the government to monitor genomic variations of Covid-19.  It checks variations in coronavirus cases across the nation to help understand how it spreads and evolves, and to suggest the best possible public health responses.

“Vaccination of all the remaining unvaccinated at-risk people and consideration of a booster dose for those 40 years of age and over, first targeting the most high-risk and high-exposure, may be considered, as low levels of neutralising antibodies from current vaccines are unlikely to be sufficient to neutralise Omicron, although the risk of severe disease is still likely to be reduced,” INSACOG said in its weekly bulletin.

INSACOG said genomic surveillance will be critical for early detection of the presence of this variant, to enable necessary public health measures. It also recommended monitoring travel to and from the known affected areas, and contact tracing of Covid-19 cases with an epidemiological link to the affected areas has been implemented along with increased testing.

The WHO has also rushed a team of experts to South Africa’s Gauteng province, the epicentre of the new Omicron variant, to ramp up surveillance and contact tracing efforts as the country grapples with rising cases of infections. Omicron, which was first identified in South Africa exactly a week ago, now has been detected in about 30 countries around the world, including India. The UN health body has, however, made it clear it had not seen any reports of deaths relating to the new Omicron variant.

Cautioning that a few clusters of coronavirus infection were reported in the country, the health ministry said some of the mutations reported on the spike gene of new Covid-19 variant Omicron may decrease the efficacy of existing vaccines. It said that the scale and magnitude of rise in cases and, most important, the severity of disease that will be caused is still not clear. The ministry, however, said that given the fast pace of vaccination in India and high exposure to Delta variant as evidenced by high seropositivity, the severity of the disease is anticipated to be low.

The ministry said while there is no evidence to suggest existing vaccines do not work on the Omicron variant, some mutations may decrease the efficacy of the jabs. It, however, underscored that definitive evidence for the new variant’s increased remission and immune evasion is awaited.

With the arrival of more passengers from the “at risk” countries testing positive for Covid-19, Union health secretary Rajesh Bhushan cautioned the states and Union territories to be extra vigilant in enforcing public health measures to contain the spread of the highly contagious Omicron variant.

On inbound international passengers, he said: “The passengers coming into your state/UT must be followed up through the surveillance mechanism and tested as per the extant guidelines of international travel.”

In a letter, Mr Bhushan said: “Some clusters of infections have been reported from some places. Active surveillance and testing is the key in detection of such clusters or hotspots. Kindly keep actively following up the number of cases, rate of testing and positivity district wise.”

In Karnataka, where the country’s first two cases were detected, the state government announced certain preventive measures like compulsory two-dose vaccination for entering malls, cinema halls or theatres, and for parents of school or college-going students. Intensifying the screening of international passengers at airports, asking educational institutions to postpone their public events, and limiting gatherings, meetings, conferences to 500 people, are among the other measures announced by the state government.

The government also ordered a probe into test reports of the 66-year-old South African national that allowed him to leave the country. Soon after he left the country, his genome sequence results showed he was infected with the Omicron variant.

In Delhi, the number of international travellers from “at risk” countries who have tested positive for Covid-19 has gone up to 12, with four more travellers arriving at the Indira Gandhi International Airport on Friday. All the passengers have been isolated and are being treated in the city’s LNJP Hospital.

Alarm bells have also been raised in Rajasthan, where nine members of a family tested positive for Covid-19, days after four of them returned from South Africa. Those who returned from South Africa have been admitted to the hospital of the Rajasthan University of Health Sciences (RUHS), and the swab samples of all nine people have been sent for genome sequencing to Jaipur’s Sawai Man Singh Hospital.

The hospital’s chief medical and health officer, Dr Narottam Sharma, said 14 samples were taken for testing from the family, nine of which tested positive for the infection. In contact tracing, it was found that four of them had returned from South Africa, he said. The official said as per the guidelines, those who returned from South Africa have been isolated at the RUHS hospital while the other five have been home quarantined.