"The BF.7's high transmissibility in China might be attributed to a low level of immunity in the Chinese population from the previous infection and possibly vaccination too," an official source said.
Meanwhile, the Centre is taking appropriate measures to remain alert amid a sudden spurt in cases in China and the US. During a Covid review meeting chaired by Union Health Minister Mansukh Mandaviya on Wednesday, experts said although there is no overall increase in Covid caseload as of now, there is a need for continued surveillance to keep a track of existing and emerging variants.
"In view of the rising cases of COVID-19 in some countries, I reviewed the situation with experts and officials today. Covid is not over yet. I have directed all concerned to be alert and strengthen surveillance. We are prepared to manage any situation," Mandaviya said in a tweet.
Keep wearing masks in crowded places: V K Paul
Following Mandaviya's review meeting, NITI Aayog member (Health) Dr V K Paul on Wednesday advised people to take the jab and wear masks in crowded places.
He urged people not to panic and clarified that there was no change in the guidelines for international air travel so far.
"People should wear masks in crowded areas. Those who have comorbidities or are elderly should especially adhere to this," Paul said.
All that you need to know about BF.7
BF.7 is a sub-lineage of the Omicron variant BA.5 and has the strongest infection ability since it is highly transmissible, has a shorter incubation period, and has a higher capacity to cause reinfection or infect even those vaccinated.
It has already been detected in several other countries, including the US, the UK and European nations such as Belgium, Germany, France and Denmark.
(With inputs from agencies)