Express News Service
BHUBANESWAR: If you think Omicron is driving the surge in new Covid-19 cases since the beginning of the year, hold on. It is the ferocious Delta that continues to be the dominant variant of concern for Odisha.
As per the latest genome sequencing data of community samples, 74.5 per cent (pc) were found to be of the Delta variant and the rest Omicron. The samples were drawn from nine districts between December 29 and January 9 and sequenced at the Institute of Life Sciences (ILS) here. The state has been witnessing a spike in new infections since January 1.
Of the 263 samples randomly drawn from the community, 196 were detected with Delta and its sub-lineages and 67 with Omicron. This was the first community sample sequencing this year as the samples do not include any foreign returnee or travellers to other states.
While the Delta sub-lineages included AY.44 and the original B.1.617.2 that had led the second wave, Omicron and two of its sub-lineages found among the community accounted for 25.5 pc samples. Seven samples were detected with BA.1, 25 with BA.2 and 35 with B.1.1.529. Most of the clinical cases in vaccine breakthrough were infected with the Delta variant.
“The findings of the genome sequencing are indicative of Delta still dominantly circulating in the community. So there should not be any complacency in management and treatment of patients with a false impression of Omicron variant which is less likely to be severe,” said a scientist of the lab.
Among the samples detected with Omicron variant, BA.2 is found among the samples with CT value of below 30, indicating high viral load. Since the variant has been detected in districts like Balasore, Khurda, Cuttack, Jharsuguda and Puri that has been fuelling the caseload, it is possible that this sub-lineage is causing the local clusters in such districts, he said.
Omicron (B.1.1.529) has now split into three sub-types – BA.1, BA.2 and BA.3. While BA.1 is dominantly circulating in Maharashtra and the first two sub-types have been found in Delhi, Karnataka, West Bengal and other states, BA.3 is yet to be detected in the country. So far 169 samples, including more than 100 from the community, have been detected with the Omicron variant in Odisha.
ILS Director Dr. Ajay Parida said Delta may be dominant as per the latest data, but Omicron sub-type BA.2 is fast replacing it in the state. “We will conduct the sequencing of 250 more community samples on Monday. The samples will include the cases from January 10. This will give a clear picture of Omicron’s presence here,” he said.