Understanding Omicron BF.7, The New Covid-19 Variant From China, And How India Should Prepare

India has done great so far and we should not panic this time too, but knowing the erratic behaviour of SARS-CoV-2, it is prudent to take precautionary measures.

The Covid-19 pandemic is dragging on too long, and there is still no respite in sight. This has thus become one of the longest pandemics the human race ever faced, surpassing the Spanish Flu that had ravaged the globe from 1919 to 1921. The current scenario is governed by two sub-variants of the Omicron variant that was first detected in South Africa in November 2021. China is meanwhile facing an unprecedented crisis due to the BF.7 variant with its tentacles spread over Japan, South Korea, Taiwan and Hong Kong. BQ.1 and BQ.1.1 sub-variants are driving the crisis in the USA, Brazil and parts of Western Europe. 

Coronaviruses And Variants

The original virus that first emerged from Wuhan in China is termed SARS CoV-2 and is a strain of the coronavirus that causes Covid-19. Severe Acute Respiratory Syndrome (SARS) is a viral respiratory disease caused by a SARS-associated coronavirus, now termed SARS-CoV-1, first identified in 2003 in China. After its origin in China, SARS-CoV-2 is constantly changing, and new variants of the virus are expected to occur. During RNA transcription, genetic changes can occur through mutations, altering the viral structure and causing variants. These variants can also acquire specific mutations of their own labelled as sub-variants. Mutations appear and cause new variants. Some variants emerge and disappear, but some of them persist. Sometimes, these mutations leave the genetic material too broken to copy, and that virus doesn't survive. 

A virus is like a tree growing and branching out — each branch is slightly different from the others. By comparing the branches and differences, scientists label them. These small differences, or variants, have been studied and identified as variants, sub-variants and sub-lineages that mimic trees with main branches, sub-branches and leaves. The original virus and viral mutations and variants are routinely monitored through sequence-based surveillance (whole genome sequencing), laboratory studies, and epidemiological investigations in several countries globally and reported to the World Health Organization (WHO). The WHO maintains a registry of Variant Being Monitored (VBM), Variants of interest (VOI), Variants of concern (VOC) and Variants of high consequence (VOHC). Some variations allow the virus to spread more easily or make it resistant to medicines or vaccines, so needs to be monitored carefully. 

Variants have been named in the Greek alphabet, to avoid confusion and geographical stigmatisation. Some remained only as Variants of Interest (VoI) (Gamma, Kappa, Eta, Iota, Epsilon, Lambda, Mu) while Alpha (B.1.1.7), Beta (B.1.351), Delta (B.1.617.2) and Omicron are termed Variants of Concern (VoC). VoC demonstrates increased transmissibility, increased disease severity and evidence of impact on diagnostics, treatments, or vaccines by a reduction in expected outcomes. By far, Delta has been the most impactful variant as it created high oxygen demand, high rates of hospitalisations and higher mortality. Studies suggest that the Delta had five times more infections than the original virus and resulted in ten times more hospitalisation and deaths. 

Let Us Understand BF.7 

The Omicron variant that is calling the shots globally is around three times more transmissible than Delta among vaccinated individuals. However, it is less lethal as it affects mainly the upper respiratory tract as opposed to Delta which impacts the lower-respiratory tract. The Technical Advisory Group on SARS-COV-2 Virus Evolution (TAG-VE), an independent group that periodically monitors and evaluates evolution of Covid-19 virus, addresses specific mutations, named B1.1.529 variant as Omicron. Unvaccinated people have higher transmissibility compared to fully vaccinated ones.

Omicron has BA.1, BA.2, BA.3, BA.4, and BA.5 lineages. When India experienced the Omicron wave, it was mainly BA.2 and a minor proportion of BA.3. It never got BA.4 and BA.5 in perceptible proportions. Currently, India has mainly the XBB variant (~70% of cases) and it is recombinant of Omicron BA.2.10.1 and BA.2.75 with the remaining cases from other sub-variants of BA.2. The USA’s BQ.1 and BQ.1.1 are sub-lineages of Omicron BA.5. 

China’s BF.7 is BA.5.2.1.7 sub-lineage of Omicron BA.5. BF.7 has R346T mutation in spike protein of the virus and can escape antibodies that have been derived from the vaccines targeted to the original Wuhan virus, especially the Chinese vaccine Sinovac. 

Contrary to the rumours, the symptoms of BF.7 infections are not different from those infected with other sub-variants of Omicron. Rhinitis (runny nose), sore throat, fever, cough, vomiting, fatigue, body ache, headache and diarrhoea are a few symptoms. However, those with severe comorbidities are more prone to develop severe diseases requiring hospitalisation, ICU and ventilator support. 

Barring mRNA vaccines from Pfizer and Moderna, all other vaccines have been developed targeting SARS-CoV-2 and Alpha variants. Since the bivalent boosters of Pfizer and Moderna mRNA vaccines that have been made with Delta and Omicron as targets, known as the "updated boosters", are so new, there is no effectiveness data available yet. People aged 60+ years or those with comorbidities vaccinated with a primary series of vaccination schedule and a booster/precaution dose from the same series may need another booster from a new series for better protection against infection, hospitalisation and deaths. 

Effects Of BF.7 On India 

Currently, India is in a much better and safer position. Credit goes to our excellent Covid management strategies, natural infection among over 90% of the population and excellent vaccination, to the extent that 75% of the population has received two doses and 25% the third or precautionary dose, making us the nation with the highest percentage of hybrid immunity. In a Malaysian study on comparison of deaths among breakthrough infection cases (Covid-19 infection post-vaccination) following Astra-Zeneca (same as Covishield in India), Pfizer mRNA (USA) and Sinovac (China), corrected to the sample size for one death after Astra-Zeneca, there were 2.5 with Pfizer and 9.5 were with Sinovac. This proves the supremacy of our Covishied that dominated vaccination (~90%). Similarly, the longevity of vaccine efficacy was ~ 4 to 5 months with mRNA against ~8 to 10 months with Covishield. That also gives our vaccinated people a relatively upper hand by way of better-lasting protection. 

Since the beginning of the Omicron wave, we have had only BA.2 and BA.3 variants, with BA.2 dominating. In something like territorial authority, this did not allow entry to the BA.4 and BA.5 variants. Though stray BF.7 cases were seen in a couple of samples in July 2022 and recently, there is no let-up in cases. India is reporting around 1,000 cases weekly with less than 15 deaths. Our healthcare infrastructure is augmented. India has just approved the world’s first intranasal vaccine and it is already part of Covid immunisation with updates on the CoWin app. 

However, knowing the erratic behaviour of SARS-CoV-2, it is prudent to take precautionary measures and do the mock drill for preparedness. Its mitigation is not difficult but requires well-coordinated multi-prong strategies involving the central, state governments and local self-governments up to the panchayat level; medical professionals and researchers; pharmaceutical and vaccine manufacturing companies as well as civil society organisations. The government has nicely coined a strategy of 4Ts + 1G: Test - Track - Treat - Teeka (vaccination) and Genome sequencing. We neither have to panic nor have to take any drastic steps like lockdown.

Some suggestions: 

1. Severe vigil on passengers arriving directly from BF.7 affected countries — from China, South Korea, Taiwan, Japan and Hong Kong or indirectly through other hubs. 

2. Escalate Covid-19 booster dose vaccination, by making it available at all clinics and hospitals. Promoting the intranasal vaccine among those who have had vaccine-hesitancy. 

3. Offer medical help and supply of vaccines to China in these hours of humanitarian crisis. Only India can do this to match the extent of the size of China. 

4. The Covid-appropriate behaviour (CAB) to be adhered to, the minimum being mandatory masking in public places, social and political gatherings, workplaces, religious places, sports events, meetings, markets etc. 

5. Escalate whole Genome sequencing to study the presence of BF.7 and the emergence of any new variants/sub-variants. 

The author is Consultant in HIV and Infectious Diseases, www.UnisonMedicare.com; secretary General, Organised Medicine Academic Guild-OMAG, President, AIDS Society of India (ASI) & Governing Council Member, International AIDS Society (IAS)

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