Exclusive | Omicron BA.2.12.1 mutant detected in COVID-19 patients in Delhi, may be driving new surge

Representative image (Source: Reuters)

A new SARS CoV 2 mutant, BA. 2.12.1, related to the Omicron subvariant BA.2 but with other distinct changes, may be driving the current surge in COVID-19 cases in Delhi and surrounding districts, top sources in INSACOG, India’s coronavirus genomic surveillance project, told Moneycontrol.

When contacted for an official version, Dr Sujeet Kumar Singh, director, National Centre for Disease Control (NCDC), the agency under Union health ministry which is leading the INSACOG project, confirmed the detection of the variant in Delhi but did not elaborate more on this.

Sources, however, said that the BA.2.12.1 variant has been detected in several samples from the national capital that underwent whole genome sequencing over the last few days.

BA.2.12.1, along with BA.2.12, the other subvariant of Omicron BA.2, was recently identified by the US Centers for Disease Control (CDC) in New York and a few other parts of the US and is said to be behind the rise in cases.

More contagious

Scientists associated with INSACOG said that this new subvariant appears even more contagious than BA.2, which was a highly transmissible Omicron subvariant and had dominated India in January before COVID-19 cases started plummeting.

Also Read | Delhi: Omicron found in 97% samples taken from deceased patients from January to March

“Our preliminary analysis has confirmed BA.2.12.1 in samples collected from COVID-19 patients in Delhi,” said a senior official at the NCDC.

He added that like BA.2, the new mutant too, appeared capable of causing reinfection in people who had been infected by the SARS CoV virus in the past.

Another scientist attached with the COVID-19 surveillance programme said that though reports from New York suggest that BA.2.12. 1 is even more contagious than the BA.2 subvariant, this is yet to be established independently in India.

Scientists are also yet to ascertain the epidemiological implications of the new subvariant though Omicron BA.2 had largely caused mild disease in the majority, mainly owing to hybrid immunity arising from vaccination and prior infection.

Also Read | COVID-19 situation in Maharashtra under control, no need to panic, says Health Minister Rajesh Tope

But some researchers have also suggested that the mutated virus, BA.2, like the other Omicron subvariant BA.1, was capable of causing only upper respiratory illness in the majority of the people and did not affect the lungs.

The new subvariant BA.2.12.1 which has now been identified in India too, is yet to be declared either as a variant of interest (VoI) or a variant of concern (VoC) by the World Health Organization (WHO).

Rising COVID-19 numbers

In India, the number of COVID-19 cases has been rising over the last few days, mainly due to the surge in cases in Delhi and the National Capital Region.

Data released by the Health Ministry on April 21 said that 2, 380 new coronavirus cases have been recorded in the country over the last 24 hours while active cases have grown to 13,433.

Some days ago, daily COVID-19 numbers in the country had fallen below 1,000 and active cases were as low as about 9,000.

On April 11, for instance, the country had reported 861 new COVID-19 cases while active cases stood at 11,058. That shows that within a span of 10 days, daily cases have risen by 176 percent and active cases have shot up by more than 21 percent.

The current rise in cases is driven mainly by Delhi, which reported 1,009 cases in the last 24 hours, and districts adjoining the national capital in Uttar Pradesh and Haryana. But an uptick in cases and test positivity rates is also being reported from states as far as Maharashtra and Mizoram.

At 2,654, Delhi, at present, has the highest active COVID-19 case load in the country. The state bulletin released on April 20 had shown that less than 1 percent of hospital beds dedicated for the treatment of COVID-19 patients are occupied.

However, some experts, such as clinician and public health researcher Dr Rajeev Jayadevan, had told Moneycontrol earlier that there could be a lag of several days between new cases and a significant change in hospitalisation patterns. Many COVID-19 patients, they say, tend to develop moderate to severe symptoms days after the initial infection.