Although COVID-19 cases are dipping in most parts of the world, the end of the pandemic is not in sight yet. Already, there are signs of a winter covid wave rising in Europe, to be followed somewhat later in the United States. Moreover, several new Omicron sub-variants are emerging across the world. Two of these, BF.7 and XBB, have been detected in India.
The concerning thing is that some of these variants are immune-evasive. As vaccine and prior infection-elicited immunity declines, there may be a rise in infections as well as deaths especially among the elderly and the immunocompromised people.
Moreover, the rate of vaccinations (2 doses) and administration of booster shots is still low in many pockets across the globe. And, administration of omicron-specific boosters (bivalent vaccines targeted against both the original virus as well as the omicron variant) is available only in limited parts of the world. In addition, use of masks and other Covid-appropriate behavior (CAB) have been relaxed in most areas of the planet.
With the dropping of temperature in the northern hemisphere, a fresh COVID wave may hit us soon, triggered by any of the new sub-variants compounded by relaxed CAB and waning of immunity especially among the elderly and the immunocompromised individuals, accompanied by co-morbidities due to the flu season.
Today, let’s discuss the issues of new Covid variants, possible COVID wave in coming winter, and the scenario in India.
New COVID Variants
Several new subvariants have been reported in various parts of the world. These include BQ.1, BQ.1.1, and XBB, among others. Based on UK data, the BQ variants, BA.2.75.2, XBB, and BF.7 are the most concerning as they have higher transmissibility and immune evasiveness (Bloomberg, Oct. 13, 2022).
The other concerning aspect is that some of these variants cannot be neutralised by monoclonal antibody drugs e.g., evusheld (a combination of tixagevimab and cilgavimab).
Europe has recorded a surge in COVID cases in the week ending Oct 2, logging an increase of 8 per cent relative to the previous week (The Mint, Oct. 12, 2022). Meanwhile, several parts of Europe still remain unvaccinated. Health authorities have urged vulnerable groups to get vaccinated against both influenza and Covid-19, prior to the expected surge.
The onset of winter is particularly foreboding as fall and winter have always been peak seasons for respiratory viruses. Due to cold weather, people will congregate indoors where viruses can spread more easily. Moreover, holiday travel and gatherings and crowding in festivities e.g., Christmas, Diwali, and new year celebrations may help spread the new strains of SARS-CoV-2 (Time, Oct. 11, 2022).
More than 1.5 million cases have been reported across Europe in the week ending Oct.2, with majority of cases coming from Germany and France. Although the daily cases are low in US, roughly 400 people have been dying every day there. According to Dr Arianna Planey, University of North Carolina, there are signs that a surge is coming. Omicron-specific boosters are yet to be available in most parts of the world and antibody therapies and drugs such as Evusheld and Paxlovid are beyond the reach of the majority of the world’s population. In addition, some of the sub-variants cannot be neutralized by these therapies.
Possible Winter Wave
An incipient Covid wave is already seen in Singapore, Europe, and possibly parts of China. As the temperature drops while we also drop our guards, and as new variants spread while immunity from prior infections and vaccinations wanes, a new wave is likely to arise. This may lead to a fresh surge in cases in parts of the world. The elderly and the immunocompromised may suffer from serious infections, and a subset of them may unfortunately die from a new COVID surge.
In the US, 2 subvariants-BQ.1 and BQ.1.1-account for nearly 11.4% of infections (HT, Oct.15, 2022). These are related to BA.5 variant, which remains the dominant variant in the US, accounting for about 68% cases. BA.2.72.2 is another variant, that experts are monitoring, which accounts for about 1.4% of cases.
The rapid rise of BQ subvariants indicate that they have either increased transmissibility or enhanced immune escape capacities. They might also be resistant to some antibody treatments.
The WHO says that scientists are now tracking over 300 sublineages of Omicron, any or some of which might trigger a fresh wave of Covid infections across the world (STAT News, Oct.6, 2022).
COVID-19 Scenario in India
The new strain, XBB, has been detected in 4 states-Maharashtra, West Bengal, Orissa, and Tamil Nadu (Firstpost, Oct. 14, 2022). It’s a combination of BA.2.75 and BJ.1 variants. It’s the more transmissible and more immunity-evasive variant found so far. XBB accounts for nearly 50% of daily cases in Singapore.
Infected persons may show signs of mild symptoms such as fever and sore throat. Though it’s the most immune-evasive variant yet, WHO has not yet declared it as a variant of concern (VoC). About 7% of cases in India is currently due to XBB, while BA.2.75 accounts for nearly 88% infections. XBB or another variant may soon dominate over all other sub-variants. The heartening news is that this strain so far has not led to more deVere infections.
Another Covid subvariant, BF.7, has also been reported from India. BF.7 is also known as BA.5.2.1.7. This strain resulted from the virus constantly evolving to become more immunity evasive. Its symptoms include sore throat, congestion, fatigue, cough, and runny nose (The Mint, Oct. 12, 2022).
We need to watch out for these new subvariants. As winter approaches, we must avoid crowding especially in indoor environments. We also must prevent crowding in upcoming festivities such as Diwali, Ningol Ckakkouba, Xmas, and New year celebrations etc. And, we must enhance the rates of vaccinations and booster shots.
Health authorities may also attempt to acquire Omicron-specific vaccines (bivalent vaccines) and treatments for immunocompromised e.g., Paxlovid and Evusheld. Meanwhile, we must enhance our vaccination and booster rates. At the same times, the authorities must take steps so that people at large continue to maintain safeguards such as masking, hand hygiene, and avoidance of crowding etc.
And, we must continue testing and genomic tracking of cases, looking for signs of any new variant(s).
It's better for all to be surprised with a positive development instead of being dismayed with a sudden onset of adverse scenario!
