Is there more than one strain of the new Coronavirus?
There has been a lot of speculation recently about two strains of the Coronavirus – namely the S and the L strain.
The alphabets refer to the names of the Amino acids in the sequence of the virus- ‘S’ denoting Serine and ‘L’ denoting Leucine. The theory is that probably from nearly the beginning of the outbreak in Wuhan the two strains co-existed. The popular theory is that the ‘S’ strain was the earlier strain which was replaced by the ‘L’ strain which had a greater propensity to spread amongst humans, and then the ‘S’ strain returned once physical distancing and other precautions were adhered to.
The ‘L’ strain has been blamed for many things - from higher transmission rate to higher virulence to higher mortality rates, though the evidence for this is lacking. The ‘S’ strain is thought to transmit the milder form of the disease. According to the leading experts in the world, however, the evidence for this is lacking – there are minor variations in the phenotyping of the Novel Coronavirus – in fact, sequence variations to the tune of thousands have been identified but the Strain remains the same.
It is natural for species to mutate. Mutations offer various advantages including improving survival benefits. Most mutations are spontaneous. During the process of multiplication or cell replication, some code or signal is corrupted leading to an alteration in the sequencing of the new offspring. As per the experts, the Human Coronavirus has, by and large, remained one entity with very very minor variations.
The gene ORF8 mutated and formed a Clade “S”. The “L” and “S” subtypes belong to the ‘S” Clade. The controversy regarding the L versus S strains will persist for some time. Rather than getting involved in advanced Virus phenotyping studies and its microbiological and genetic implications what is important for us as clinicians and for the people at large is to understand the basics of prevention – these remain the same:
1. Physical distancing – I use the phrase “physical distancing” rather than the more prevalent “social distancing” with a very specific purpose – thanks to social media- Whatsapp, Facebook, Twitter, Instagram, Tik Tok, etc we continue to be socially near. The distance we need to maintain is physical, not social. Two meters or more is good.
2. Frequent hand washing – especially when returning from outside, before leaving the washroom and before eating a meal.
3. Hand sanitization- where it is difficult or impractical to hand wash please use a minimum 70 percent alcohol-based hand sanitizer.
4. Use of face mask- whenever outside the house kindly use a mask which is made of minimum double-layered cloth and which covers the mouth and nose.
5. Avoid touching your nose, eyes, face with your hands/ fingers.