Top scientists and doctors in India said on Thursday that it’s too early to understand the nature and severity of the new sub-variant of Omicron — BA.2.75 — reported in the country.
The highly transmissible Omicron variant of COVID-19 has been driving a surge of infections globally. The World Health Organization said it is monitoring the BA.2.75 variant, which has been reported from over 10 countries.
Also read: Data | Omicron variant BA.2 and its sub-lineages responsible for latest COVID-19 surge
“About this new variant — so far there is no data available, except the increasing COVID numbers, which makes it difficult to arrive at any conclusion about the severity of the new variant,’’ said Pragya D. Yadav from the Maximum Containment Laboratory at the Indian Council of Medical Research-National Institute of Virology (NIV), Pune. She said the rising cases were due to many other reasons. “It’s too early to comment on the nature of the variant,’’ added Dr. Yadav.
Seconding this, Dr. Rajeev Jayadevan, co-chairman, Indian Medical Association’s national COVID-task force, said that in India, the limited genomic surveillance data indicate that it is predominantly the BA.2 sub-lineages that are circulating. Among them, BA.2.75 has received attention from experts around the world because of a combination of mutations that makes it more likely to be immune evasive.
“We do not have the actual clinical profile yet, and the limited data on BA.2.75 cases from India indicate these are mild or asymptomatic. But it is wrong to comment one way or the other based on a few cases,’’ he said.
India’s Omicron wave started in December 2021 with BA.1, which was then taken over by BA.2, BA.4 and BA.5, which are Omicron sub-lineages of greater concern and leading the surges in Europe.
“BA.2 is an upgraded version of Omicron, which is why it displaced BA.1. Naturally, as the virus adapts further to escape human immune response and also to transmit faster, it will create changes in its genetic code based on a continuous study of human immune response. The special ability of Omicron is that it is weakly immunogenic, which means that the immune response following an Omicron infection is not good enough to protect against repeated infections by its own sub-lineages. For example, if someone was infected with BA.1, that person is not immune to BA.4 or BA.5 infection, even though they are all within the Omicron sub-group,’’ said Dr. Jayadevan.
In India, Maharashtra is among the States that have been reporting a large number of COVID-19 cases. Speaking on the ground situation, Manjusha Agarwal, senior consultant-internal medicine at Global Hospital, Parel , Mumbai, said that they have had cases of this variant. “We are seeing many OPD patients with COVID-19 everyday. However, the new variant so far seems to be mild and typically lasts for 2 to 3 days. Also over the past six months, the virus seems to be causing less severe disease. However, elderly people with co-morbidities should be very careful. Also, we are seeing many patients with fever and respiratory symptoms who do not have COVID-19, so there is an emergence of non-COVID viral fevers which cause respiratory symptoms. Hence it is important to visit your doctor for faster diagnosis of your illness and rapid treatment and recovery,” Dr. Agarwal said.
