What is the new Covid variant BF.7 and should India be worried?

The Omicron sub-variant has raised fears of another wave of the pandemic, as infections surge in China

Under tightened Covid-19 rules, a passenger is tested for the coronavirus after arriving at Chennai International Airport, in eastern India. EPA

India has approved a home-grown intranasal Covid-19 vaccine to be used as a booster dose for adults, in an effort to protect its citizens from a new coronavirus variant raging in China.

The needle-free vaccine Incovacc, manufactured by Bharat Biotech, will be available to over-18s, after authorities gave their approval on Friday.

The country's drug authority in September gave the vaccine restricted approval for use in emergency situations.

This wider approval comes amid fears of a fresh wave of the pandemic, following a surge in cases in China and other countries.

China has been hit by severe outbreaks driven by Omicron sub-variant BF.7 in recent weeks.

India had reported only four cases of the sub-variant as of December 23.

What is the Omicron variant BF. 7?

BF.7 is a sub-lineage of the Omicron variant — the dominant variant circulating globally of the Sars-CoV-2 coronavirus.

It has a 4.4-fold higher neutralisation resistance than the original D614G variant, according to a study published in the Cell Host and Microbe journal.

This means, in a laboratory setting, antibodies from a vaccinated or infected individual are less likely to destroy BF.7 than the original virus first detected in the Chinese city of Wuhan in December 2019.

While BF.7 is not the most resilient sub-variant, it has a higher transmission rate — with an R-value of 10 to 18.6.

R-value measures the number of people infected by one person. This means, a person infected with BF.7 will transmit the virus to an average of between 10 to 18.6 other people.

This sub-variant also has a shorter incubation period and a higher capacity to cause reinfection or infect even those vaccinated.

What are the symptoms?

The symptoms of BF.7 infection are similar to those of other Covid-19 variants, such as fever, sore throat, runny nose and cough. Some patients may also experience diarrhoea and vomiting.

While the variant may not cause severe complications, early detection and isolation of cases is crucial, because it is spread more easily.

What is the impact in China?

The variant is wreaking havoc in China, with more than 60 per cent of cases there reportedly caused by BF.7.

It also accounted for more than 5 per cent of the cases in the US and 7.26 per cent of cases in the UK in October.

Of India's four confirmed cases of BF.7, three were in the western state of Gujarat and one in Odisha, in the east.

Fears for India

India's government has urged people to resume precautions such as wearing face masks, as it seeks to avoid a repeat of the surge caused by the Delta variant that brought the health system to the verge of collapse.

The nation of 1.4 billion people has experienced several waves of Covid-19 since the outbreak of the pandemic in 2019. At least 530,000 people died, out of about 44 million infected.

To avoid a similar situation, India has started genome sequencing for early detection of BF.7 and other new strains, approved nasal vaccine as booster dose and has also begun randomly testing international passengers arriving at its airports.

Many experts believe that while India may experience another wave of the pandemic, it will not be as devastating as Delta, as most Indians have acquired hybrid immunity developed through infection and vaccines.

“We are about eight months out since India last had a wave, which means immunity against infection has waned. India is due for another wave,” Dr Rajeev Jayadevan of the Indian Medical Association told The National.

If a fast-spreading variant arrives in India, many people will pick up an infection but mortality will be lower than from the Delta variant, he said.