BF.7: THE NEW WAVE?

How much new (different) is the subvariant BF.7?

BF.7 is accounted for more than 5 per cent of Covid-19 cases in the US and 7.26 per cent in the UK in October 2022. Cases of this variant are on raising hand from the last 3 months. BF.7, short for BA.5.2.1.7, is a sub-lineage of the OMICRON variant BA.5. BF.7 is believed to have an R0, or basic reproduction number, of 10 to 18.6. BF.7 carries a specific mutation, R346T, in the spike protein of SARS-CoV-2 (a protein on the surface of the virus that allows it to attach to and infect our cells). This mutation, which we also see in BF.7’s parent variant BA.5, has been linked with enhancing the capacity of the virus to escape neutralising antibodies generated by vaccines or previous infection. Since the COVID variant OMICRON emerged in late 2021, it has rapidly evolved into multiple subvariants. The subvariant, BF.7, has been identified as the main variant spreading in Beijing and is contributing to a wider surge of COVID infections in China

Reports of 2 patients in Gujarat are coming in showing they recovered at home. Does it make the sub-variant less fatal?

BF.7 is believed to be less fatal as compared to the previous deadly delta variant and other sub-variant of omicron. The symptoms of an infection with BF.7 are similar to those associated with other omicron subvariants, primarily upper respiratory symptoms. Patients may have a fever, cough, sore throat, running nose and fatigue, among other symptoms. A minority of people can also experience gastrointestinal symptoms like vomiting and diarrhoea. BF.7 may well cause more serious illness in people with weaker immune systems.

Is it more infectious than before?
The BF.7 variant is reportedly more infectious than the other variants of coronavirus known so far. The R0 value of this mutant as per studies is approximately 10-18.6 which means that any infected individual can infect 10-18.6 people around him. Reports from China indicate BF.7 has the STRONGEST INFECTION ABILITY out of the omicron subvariants in the country, being quicker to transmit than other variants, having a shorter incubation period and with a greater capacity to infect people who have had a previous COVID infection, or been vaccinated or both. To put this into context, BF.7 is believed to have an R0, or basic reproduction number, of 10 to 18.6. This means an infected person will transmit the virus to an average of 10 to 18.6 other people. Research has shown omicron has an average Ro of 5.08. The high transmission rate of BF.7, taken with the risk of hidden spread due to the MANY ASYMPTOMATIC CARRIERS, is understood to be causing significant difficulty in controlling the epidemic in China.

How immunity will play its role with the new BF.7 variant?
Compared with the BA.1, BA.2 and BA.5 variants detected previously, Omicron BF.7 has more immune escape capability, a shorter incubation period and a faster transmission rate. These mutations give BF.7 some immune-evasive abilities, which means it can escape immunity from the vaccine or previous infection.

How India can buckle up before the situation goes out of hand?
India with its focus on the five-fold strategy of testtrack-treat-vaccination and adherence to COVIDappropriate behaviour has been able to restrict the transmission of the coronavirus. BF.7 has been detected in several other countries around the world including INDIA, the US, the UK and several EUROPEAN COUNTRIES such as Belgium, Germany, France and Denmark. Despite BF.7’s immune-evasive characteristics, and worrying signs about its growth in China, the variant seems to be remaining fairly steady elsewhere. Outside of India, mRNA vaccines like Pfizer and BioNTech’s Bivalent vaccine and Moderna’s vaccine are being used from the point of view of boosting. India needs to buckle up. BF.7 may well cause more serious illness in people with weaker immune systems. At present, no vaccine being used in India is a bivalent vaccine. India needs BIVALENT vaccines, which target omicron alongside the original strain of SARS-CoV-2.

What age group is highly sensitive to this new sub-variant?
Old age people, immunocompromised patients, pregnant females etc. are more prone to the infection by this variant.

Should India impose early restrictions on international flights?
BF.7 is highly infectious and has high transmissibility, hence to prevent the spreading of this highly contagious disease international travelling should be monitored carefully. The situation looks different ONLY IN China. BF.7’s high R0 might be due in part to a LOW LEVEL OF IMMUNITY in the Chinese population from the previous infection, and possibly vaccination too. However, we should be cautious about the data from China as it’s based on reports, not peer-reviewed evidence yet.

What is the best recommendation to stay safe at this time?
FDA approved the second booster dose of the Pfizer-BioNTech COVID-19 Vaccine or Moderna COVID-19 Vaccine which may be administered to individuals 50 years of age and older at least 4 months after receipt of a first booster dose of any authorized or approved COVID-19 vaccine. The emergence of BF.7 and other new variants is concerning. But VACCINATION is still the best weapon we have to fight COVID. India needs BIVALENT BOOSTERS, which target omicron alongside the original strain of SARS-CoV-2. At present, no vaccine being used in India is a bivalent vaccine. Outside of India, mRNA vaccines like Pfizer and BioNTech’s Bivalent vaccine and Moderna’s vaccine are being used only from the point of view of boosting. The best recommendation at this point is to provide boosters (though the effect is short-lived) to those who have weak immunological defences.