Category : Research
There still remains a lot to be learned about the factors fueling emergence of SARS-COV2 variants, and why do we experience ‘waves’. However, surely the ‘pause’ & ensuing sudden ‘surge’ we saw when 2nd wave emerged after a long time gap from the first with a big-bang, totally unanticipated & surpassing the known infection figures of all the countries across the globe, was unprecedented. And that happened when the trend from Dec. 2020 onwards was on sharp decline & most started believing that coronavirus may become history in India after March ‘2021.
The way the 2nd wave of coronavirus appeared suddenly & sharply without pre-warning causing devastation as far as severity, number of infections and deaths are concerned, it is difficult to believe that it could simply be due to human intervention caused by ‘opening up’ after a ‘strict lockdown’ ! ‘Lockdown’ and ‘opening ups’ must have helped in putting a control on rapid transmission & increased infection rates after the restrictions were lifted, respectively, however, do not explain its increased contagious & virulent nature, additions of more symptoms to the existing list increased number of deaths especially of younger people due to heart failures and more importantly deaths of those who found themselves fully recovered & returned home from hospitals after defeating the first wave coronavirus.
Since human phenomenon does not appear to be the sole reason for ‘waves’ & ‘pauses’, we need to understand how evolutionary struggle for survival leads to speciation and emergence of new variants through mutations! And when it comes to a virus we know that rapid yet continuous mutations are key to its survival !
Since evolution of coronavirus, is creating more virulent and contagious variants e.g. Delta (B.1.617.2) & Delta plus (B.1.617.2.1/AY.1), one has to wait & see what twist & turns this pandemic unveils (which will be directly related to the emergence of their infective nature) till it ends up producing the one which is mildly infectious, and its further mutations stop producing contagious and virulent varieties! It is pertinent to mention that last 6-7 months have seen emergence of a large no. of new variants caused by mutations (≥ 3 dozen recorded so far) in the spike protein, having characteristics of spreading faster & capable of countering antibodies produced by infection due to previous version(s) of SARS-CoV-2 or vaccines.
Based on the understanding developed so far, Delta variant (B.1.617.2) is likely to be more damaging because it appears to bind more strongly with lung receptors and may not be countered by the body’s immunity achieved through vaccinations.
It appears that the third wave is already there and is a matter of concern in countries such as the UK, the US, Russia and obviously in several states of India where we are seeing the infection figures rebound post the downward turn seen in June this year. Since the waves are the result of the support provided by biological ecosystems, we are living in, we may see many more waves before coronavirus says final goodbye or becomes non-damaging to human to a great extent or almost all of us develop the required herd immunity either through natural infection or through vaccines. One thing, however, is quite apparent that coronavirus is going to cohabitate with us much longer than anybody would have thought & may not be easy to control because of its nature and our habits.
Pre-symptomatic period of 3-5 days before the appearance of the visible or observable symptoms is the major problem in timely handling the COVID-19. The silver lining, however, is that ≥85% of the infections are either asymptomatic or too mild to worry about. Around 15% of the total infections, which are further affected with co-morbidities, weak human immune system, either due to food, immunosuppressive drugs, habits & / or life-style issues or more importantly fear, end-up with having severe infection requiring oxygen. The percentage of people needing ventilation is usually less than 5%. And the good news is that the recent
Studies carried out by researchers at Washington Univ., in St. Louis, confirming (Nature 28 June, 2021) the presence of antibody producing cells (against the virus) in the bone marrow of COVID-19 patients, gives a hope that the SARS-CoV2 infection acquired induced immune response may be robust enough to provide sustainable protection against the virus.
The studies suggesting that vaccines may also create similar immunological response further increases hopes to contain the spread of virus, however, one has to wait & see how these vaccines will counter the continuously emerging novel variants. Wearing masks appears to help a bit in keeping SARS-CoV-2 infections at bay & the strength of an individual’s immunity in avoiding the severity due to COVID-19, but believing and feeling confident that someone is impervious to infection, is as good as living under delusion. Also knowing the fact that even those who had taken vaccines have succumbed to COVID-19, it is important for every individual to find a way or modify life-style, behavior and habits to help them joining the elite group of 85% or more, who either had mild symptoms or came out of the infection without realizing about it. The examples of senior citizens with ≥100 year of age and also affected with co-morbidities beating coronavirus, suggest that this target is well within everyone’s reach !!
(Acknowledgements:The undersigned sincerely thanks Dr. Satinder Singh for Scientific editing & Ms. Mousumi Guha for giving it the present shape).