Omicron variant: Government steps up contact tracing for Omicron sub-variants
“Contact tracing has been intensified once again… So far, no immediate clusters have been observed in the country,” NK Arora, head of India’s National Technical Advisory Group Covid Task Force on India, said on Monday. vaccination (NTAGI). “We want to leave no stone unturned to complete the genome sequencing; wastewater monitoring has also been extended to more than 50 sites.”
Both subvariants, first reported in South Africa earlier this year, are now reported in several countries. They are responsible for the fifth wave in South Africa.
Experts said the BA.4 and BA.5 shared a similarity with the BA.2 variant, the dominant sub-variant in India during the third wave.
“The antigenic properties are further away from BA.1 but not very far from BA.2. So antibodies against BA.1 won’t be as effective in preventing reinfection. That’s why the increase in BA infections. 4 and BA.5 is seen in countries with the BA.1 Omicron wave,” said Anurag Agrawal, former head of the Insacog laboratory consortium and chair of the World Health Organization’s Virus Evolution Technical Advisory Group. “The similarity to BA.2 may be sufficient to keep the risk of re-infection low in areas where BA.2 has caused large waves, for example most parts of India,” a- he added.
Shahid Jameel, a leading virologist, said BA.4 and BA.5 have additional mutations in the BA.2 lineage of the Omicron variant.
The data from South Africa suggests no significant difference in severity, he said, adding: “Maybe no different, but the severity also depends on the population – vaccinated or not.”
Although there is no evidence of high severity due to infection, Agrawal said that in a population where everyone was either infected or vaccinated or both, the severity would be low anyway.