BA.2.75, other Omicron sub-variants need to be monitored as they can trigger reinfections: Dr N K Arora
However, many of the sub-variants have not been associated with severe disease, said Dr N K Arora, chairperson of the Covid working group, National Technical Advisory Group on Immunisation.
India has not reported a new Covid variant of concern in the past six months. However, there is a need to closely monitor the transmission dynamics and virulence of some Omicron sub-lineages as many of these can trigger reinfections, according to Dr N K Arora, chairperson of the Covid working group, National Technical Advisory Group on Immunisation (NTAGI).
"Across the country, Omicron's BA.2 and its sub-lineages, including BA.2.38, are the dominant strains. Recently, BA.4 and BA.5 were found in some 10 per cent of samples. BA.2.75 was also detected. Many of them can trigger reinfections, but they have not been associated with severe disease. Overall, the sub-lineages are evolving and their dynamics need to be closely monitored," Dr Arora was quoted as saying in a TOI report.
On Thursday, India reported 18,930 new COVID cases in the last 24 hours, according to the Ministry of Health and Family Welfare.
According to Dr Arora, the ongoing spike is part of the third wave, not a fourth. “There is another dimension to this. Cases are mostly limited to metros and big cities with high population density. Recently, smaller towns also started to see upticks. Population density, increased travel and gatherings, along with poor adherence to Covid protocols, are factors linked to surges. Important thing is, most patients these days are vaccinated and go on to have common-cold or mild influenza-like illnesses," he said.
Meanwhile, WHO Director-General Tedros Adhanom Ghebreyesus expressed concern over sub-lineage BA.2.75 of the Omicron variant which has been detected in India and other countries. "The World Health Organisation is tracking this," he said.
WHO Chief Scientist Soumya Swaminathan said in a video posted on Twitter that there has been an emergence of a sub-variant that is being called the BA.2.75. It was first reported from India and then from about 10 other countries.
She said: "There are still limited sequences available of the sub-variant to analyse, but this sub-variant seems to have a few mutations on the receptor-binding domain of the spike protein. So obviously, that's a key part of the virus that attaches itself to the human receptor. So we have to watch that. It's still too early to know if this sub-variant has properties of additional immune evasion or indeed of being more clinically severe. We don't know that. So we have to wait and see.
She further said WHO is tracking it and the WHO Technical Advisory Group on SARS-CoV-2 Virus Evolution (TAG-VE) is constantly looking at the data from around the world. "And at any time if there is an emergence of a virus that looks very different from a previous one, enough to be called a separate variant of concern, then the committee will do that."
The WHO weekly epidemiological update on COVID-19, released July 6, said that globally, the number of new weekly cases increased for the fourth consecutive week after a declining trend since the last peak in March 2022.
During the week of June 27 to July 3, over 4.6 million cases were reported, a figure similar to that of the previous week. The number of new weekly deaths declined by 12% as compared to the previous week, with over 8100 fatalities reported. As of July 3, 2022, over 546 million confirmed COVID19 cases and over 6.3 million deaths had been reported globally.
The COVID update said that among Omicron lineages, the proportions of BA.5 and BA.4 continue to increase. BA.5 has been detected in 83 countries. Although BA.4, which has been detected in 73 countries, is also rising globally, the rate of increase is not as high as that of BA.5.
The South-East Asia Region has been reporting an increasing trend in cases since early June, with over 157,000 new cases reported, a 20% increase as compared to the previous week.
Five of 10 countries (50 per cent) for which data are available showed increases in the number of new cases of 20% or greater, with the greatest proportional increases observed in Bhutan, Nepal and Bangladesh. The highest numbers of new cases were reported from India (112,456 new cases, an increase of 21 per cent), Thailand (15,950, an increase of 6 per cent) and Bangladesh (13,516 new cases, a 53 per cent increase).
The number of new weekly deaths in the region increased by 16 per cent as compared to the previous week, with over 350 new deaths reported.
The highest numbers of new deaths were reported from India (200 new deaths, a 39 per cent increase), Thailand (108 new deaths, a decline of 14 per cent), and Indonesia (32 new deaths, an increase of 7 per cent).
WHO Incident Manager COVID-19 Abdi Mahamud said that now is not the time to declare that the pandemic is over. "We're still in the midst of the pandemic and the virus has a lot of force left. So whether it is the BA.4 or BA.5 or BA.2.75, the virus will continue. It does what it does good," he said adding that people and communities must continue to wear masks, avoid crowds and ensure that the most vulnerable and high-risk population is protected.