BF.7 strain is reportedly the most dangerous variant driving the current surge in China, but three other variants are also contributing to this. China’s Covid situation is still grim, though the data aren’t freely available. It seems BF.7 accounts for only 15 per cent of cases in China. The rest is attributed to three other variants: BN and BQ series (combined, 50%), and SVV (10-15%) (The Health Site, Dec. 29, 2022).
BN, BQ, and SVV have extensive mutations in the spike protein enabling them to evade vaccine-induced immunity.
Another concerning thing is that, according to some reports, another Omicron subvariant in China, BA.5, may be evolving to enable it to attack the brain (India TV, Dec. 30, 2022). This is in contrast with the widely accepted view that viruses usually evolve to become less dangerous. However, other scientists caution that the findings from studies in mice must not be extrapolated to humans without further studies.
One more worry is that, unless the spike in China is stopped soon, China may soon become a breeding ground for new Covid variants (India Today, Dec. 29, 2022). With the easing of restrictions, the virus is now free to move among a huge population-majority of which lack natural immunity and many of whom remain unvaccinated. This may make China a fertile ground for new variants.
More than 130 Omicron lineages have been detected in China over the last three months. These include XXB and BQ.1 and their sublineages which have been spreading in US and parts of Europe. However, BA.5.2 and BF.7 have been main Omicron strains found in China.
XBB.1.5 Variant in India
The first case of XBB.1.5 has just been detected in Gujarat (The Economic Times, Dec. 31, 2022). XBB is a recombinant of two sub-variants of BA.2. XBB.1.5 is a descendant of XBB which is believed to bind more tightly to the ACE2 receptor. That’s why this strain has higher levels of infectivity. It accounted for 40% of new surge in infections and hospitalizations in US.
XBB.1.5 is one of the most immune-evasive strains known to date. It is also one of the most effective variants that can enter and infect human cells. It causes hospitalizations wherever it’s dominant.
India has also seen a slight rise in daily cases. India logged 226 new cases in last 24 hours (India TV, Dec. 31, 2022). Also, several incoming international passengers have been found positive in many cities in India. India’s booster shot rate is still low (just about 28%). And, protection from vaccines decline over time. The country need to ramp up booster dose administration for legible people. We may also consider the need for 4th dose for the elderly and the immunocompromised people.
The official vaccination data for Manipur is not known to the author. However, according to various sources, the single dose and full vaccination rates seem to be still abysmally low. The boosting rate may be even much lower. In view of the surge in China, the possibility of new strains emerging, we must enhance the level of single dose administration and boosting rates; and full vaccination rates, if possible
Need for Booster Shots
Compared with single-dose and double-dose rates, India’s rate of booster shot administration is still quite low. According to government data, only 28% of the eligible population have received a booster shot (Business Today, Dec. 22, 2022). That means about 72% of the population is yet to receive the booster shot. This booster rate is too low in view of dangerous variants such as BF.7.
India (and Manipur) needs to aggressively accelerate the rate of administering booster shots. In Manipur, the relevant health authorities must take steps to increase the booster shot administration in the near future. In addition, the rates of single and double dose shots must also be increased, if necessary. This time, we may try the mix-and-match strategy of booster administration. That means if a person has earlier received two doses of CoviShield, he/she may now be given a third shot of another vaccine (maybe the new nasal vaccine that India has recently approved).
The mix-and-match boosting (heterologous boosting) is possibly a better tactic than using homologous boosting (Indian Express, Dec. 24, 2022). This strategy may trigger enhanced immune protection. It also gives more options to people to get booster shots as the vaccine they used earlier may be out of stock.
New Covid Drugs
A new drug made by a Japanese company (Shionogi) has been recently approved (fiercepharma.com, Nov. 22, 2022). The new drug is called Xocova. It would, hopefully, give a stiff competition to Paxlovid of Pfizer, and Lagevrio, the antiviral drug of Merck.
An experimental pill called VV116 has also been found effective at curbing mild to moderate illness in a phase-3 trial in China. The new pill also has fewer side effects than Paxlovid. These side effects could arise from complications of cross-reactions with other medications for hypertension, seizures, and insomnia etc. The new pill has been made by Junshi Biosciences and Vigonvita Life Sciences and is a pill form of the intravenously administered remdesivir.
Need for Scaling-up Vaccinations
In view of the China surge, possible rise of new strains and the dip in immune protection over time, there’s the urgent need to ramp up vaccination rates in India (and Manipur).
The full vaccination rates must be scaled up to 90 per cent, and single dose administration to 100 per cent, if possible, in the next few weeks. In addition, the rate of booster administration may be ramped up from the current 28% to 50%, at least, in the next few weeks, if possible. The relevant authorities may also consider giving a fourth dose to the elderly and those with weak immune systems.