The Union government, on Wednesday, said it has detected a new ‘double variant’ and 771 variants of concern (VOC) of the novel coronavirus in 18 states, including Maharashtra, Kerala, Andhra Pradesh and Telangana. These variants have not been detected in numbers sufficient enough to explain the recent spike in COVID-19 cases in several states. It should be noted that occurrence of mutations is natural in viruses, and according to experts, coronaviruses are the slowest mutating viruses.
The Indian SARS-CoV-2 Consortium on Genomics (INSACOG), which is a group of 10 national laboratories established by the Union Ministry for Health, found the 771 variants of concern and in 10,787 samples shared by Indian states and Union Territories. Among the 771 samples where VOCs were identified, 736 were positive for viruses detected in the United Kingdom (B.1.1.7), four samples were positive for viruses detected in South African (B.1.351), and one sample was found positive for viruses detected in Brazilian (P.1).
An analysis of the samples from Maharashtra has revealed an increase in the fraction of samples with the E484Q and L452R mutations, which is ‘double variant’ or a variant with two mutations. These mutations have been previously detected in other countries. E484Q mutation has been found in 11 countries, while L452R mutation has been detected in about 22 countries.
According to the Consortium, this leads to “immune escape and increased infectivity.” ‘Immune escape’ or immune evasion happens when the immune system of the (humans in this case) is unable to recognise the pathogen, and hence is unable to respond to it and eliminate it.
These mutations have been found in about 15-20% of samples and do not match any previously catalogued VOCs. Although these have been categorised as VOCs, “they require the same epidemiological and public health response of ‘increased testing, comprehensive tracking of close contacts, prompt isolation of positive cases and contacts as well as treatment as per National Treatment Protocol’ by the States and Union Territories,” INSACOG added.
Another variant, the N440K, which is associated with immune evasion, has been found in 123 samples from 11 districts of Kerala. A total of 2,032 samples from 14 districts of the state were sequenced. This same variant was found in 33% of samples from Andhra Pradesh as well, and in 53 of 104 samples from Telangana.
This variant has also been reported from 16 other countries, including the United Kingdom, Denmark, Singapore, Japan and Australia. According to INSACOG, “As of now, these can be, at best, said to be variants under investigation.”
Scientists across the world are categorising new variants under two categories: ‘under investigation’ and ‘variants of concern’. “Variants of concerns means the virus is growing fast. For example, if there are more infections in clusters, the concern is to see whether the immunity with the main virus or by vaccination will protect people infected by the variant,” explained Dr Jacob John, virologist and former professor at the Christian Medical College, Vellore.
“These are variants described in other countries and some having more mutations, which is expected. Mutations are the norm for this virus. Some mutations, however, may increase the transmissibility (the ability of a disease to pass from one person to another),” said Dr Jacob John.
Irrespective of the new mutations, people should continue to take the vaccine, said Dr Jacob.