“Survival of the fittest” reminds us of Charles Darwin, who popularized this concept of natural selection driving evolution. The global pandemic caused by SARS-CoV2 has demonstrated this concept to an extent.
In this present context of the Covid19 pandemic, who is the ‘fittest’?
Two Indian scientists at National Institute of Biomedical Genomics (NIBMG), Kalyani, Bengal, are helping the world understand this very question. According to their findings, the “A2a” strain has emerged as the queen of all known strains till now! They did a large-scale study of 3,636 SARS-CoV2 genome sequences isolated from 55 countries and found that 1854 (51%) of the samples belong to the A2a type. In India, 16 out of the 35 sequences (45%) constitute the A2a type. Thus, it appears that this strain is the fittest of the 10 strains that emerged from the ancestral type “O” which was first reported in Wuhan, China.
According to Prof. Partha Majumder, a senior geneticist at NIBMG, “All the other strains have nearly vanished. It is the type A2a, which has replaced the other types in most areas, while some areas still have type O.”
Dr. Nidhan Biswas, who is the first author of this study, pinpointed a change or mutation on the 614th amino acid of the spike protein that decorates the virus.
“RNA viruses have high mutation rates. Almost all regions with SARS-CoV2 show high variation except for a few conserved regions. Type A2a has an Aspartic acid to Glycine amino acid change at the 614th position.”
If we look at the present statistics, India is in a peculiar position in terms of Covid19 testing, The Indian government claims that the testing rate is apt while critics say India has poor testing numbers. As of April 24th, the testing rate for India was 380 persons tested per million, which is way too low compared to the International standards, which is around 5,897 persons tested per million.
Prof. Majumder said, “Unfortunately, we are not doing enough screening, and this could lead to a huge burst of cases when lockdown is lifted. The lockdown cannot go on for ever. It was meant to ramp up isolation and quarantine facilities alongside and for increasing medical infrastructure to support severe to critical cases. This has to be supported with continuous and sufficient testing.”
Similarly, Dr. Biswas warned that history could repeat itself. According to him, “Past pandemics have exhibited a second wave, so without proper testing, the situation could worsen.”
What is the way out and how would their study help?
Prof. Majumder states, “This analysis has made it clear that A2a is the predominant strain and experts from across the world trying to design a vaccine should keep this information in mind. Even if a cocktail of attenuated weakened viruses are used to make a vaccine; the A2a type must be there. Also, the sequencing of isolates should go on for a minimum of one year to determine whether A2a continues to stay the predominant one.”
Dr. Nidhan Biswas said, “In the next 2 to 3 months, we can provide more information on regions of this virus that mostly remain the same (conserved regions).”
Coronavirus- a game changer?
This pandemic has caused a global economic crisis. How is this going to impact science in India? When asked, Prof. Majumder responded, “There would be fund cuts for research. Funding will probably be channeled toward R&D activities in infectious diseases. But pandemic or no pandemic, less than 1% of India’s GDP is invested in scientific research… which really is meager.”
This pandemic is an eye opener and policy makers in India need to seriously rethink. Medical facilities and research, keeping in mind the rural population of India, need to scale-up to be better equipped to tackle such issues in the future.