Studies show XBB.1.16 is not clinically more severe

According to government data, XBB.1.16 is driving the current Covid-19 surge across the country, with at least 50% of the genome sequenced samples testing positive for it.

The XBB.1.16 sub-variant of the Omicron strain of the SARS-CoV-2 virus that causes Covid does not exhibit higher clinical severity according to preliminary results from laboratory studies being conducted in the country to know disease characteristics, according to people familiar with the matter.

According to the World Health Organisation (WHO), mutations at position 478 of the SARS-CoV-2 spike protein have been associated with decreased antibody neutralization, increased transmissibility, and pathogenicity. (REUTERS)

“ICMR studies to know how severe the sub-variant is have found that XBB.1.16 is not more severe, which the fewer hospitalizations and deaths owing to Covid-19 also seem to corroborate. There has been a surge in cases over the past few weeks, and we may continue to see an increase in daily cases for another 8-10 days before the numbers start to come down,” said a senior government functionary, requesting anonymity.

According to government data, XBB.1.16 is driving the current Covid-19 surge across the country, with at least 50% of the genome sequenced samples testing positive for it.

XBB.1.16 is a recombinant of BA.2.10.1 and BA.2.75 and has three additional mutations in the SARS-CoV-2 spike protein (E180V, F486P and K478R) compared to its parent lineage XBB. The F486P mutation is shared with XBB.1.5.

According to the World Health Organisation (WHO), mutations at position 478 of the SARS-CoV-2 spike protein have been associated with decreased antibody neutralization, increased transmissibility, and pathogenicity.

Scientists at The Indian Council of Medical Research (ICMR)- National Institute of Virology in Pune isolated the virus and were conducting studies on markers of disease severity.

“It is not a Covid-19 wave and the surge that you are seeing currently can also be attributed to increase in Covid-19 testing. In fact, Covid in India is moving into the endemic stage,” added the government functionary.

According to the World Health Organisation, global laboratory studies on the sub-variant also do not show increase in disease severity.

“…till March, 712 XBB.1.16 sequences were reported from 21 countries. However, so far reports do not indicate a rise in hospitalizations, ICU admissions, or deaths due to XBB.1.16. Further, there are currently no reported laboratory studies on markers of disease severity for XBB.1.16,” read WHO’s latest epidemiological update.

According to people familiar with the matter, hospitalisations due to Covid-19 remain less than 1% in India.

“Most of those admitted in hospitals are admitted due to co-morbid conditions. The number of Covid positive patients needing admission is minuscule, which tells us that there is no need to panic. We need to be careful and observe Covid appropriate behavior,” said a senior health ministry official, requesting anonymity.

India on Wednesday reported 7,830 new Covid cases taking the active caseload in the country to 40,215.

With the rising cases, the focus is back on the booster (third) dose with the experts urging people to take the third Covid-19 shot, especially those falling under the high risk category. Nearly three of every four people eligible for the booster are yet to take it.

“This is the time for people, who haven’t taken their third dose, to take it, especially high-risk population such as elderly, people with co-morbidities, smokers, obese etc as these are all risk factors for developing severe Covid disease,” said Dr Sandeep Budhiraja, head, department of internal medicine, Max Super Speciality, Saket.

Covid vaccine makers are also preparing to manufacture shots in case there is an increase in demand. On Tuesday, Adar Poonawalla, CEO, Serum Institute of India, urged people to take the third shot. He said his company’s second Covid vaccine, Covovax was excellent against all variants and also approved for use in the US and Europe.

According to people familiar with the matter, Serum already has six million doses of Covovax available in stock and the company can restart production of its first vaccine, Covishield, at short notice. .

“There is some volume of Covid vaccine doses available with the centre, and states are also free to procure depending on demand for precaution dose. As of now, there does not seem to the need to procure more doses,” said the government functionary cited above.