Dr Ajit Bhagwat
The rapid surge of the second wave of Covid-19 has taken every one by a shocking surprise. Not that it was totally unexpected, however the manner in which the number of cases had declined in October to January had raised hope that the country had turned the corner. Are there any differences between the first and the second wave? Even a casual observation reveals the following striking differences 1. A large number of contacts around the index case get infected 2. The incidence of entire family getting affected is very common. This indicates a very high infectivity of this virus defined by the R0 (R naught) value in scientific terms. Why has the infectivity suddenly gone up? The virus seems to have suddenly started escaping the immune system (innate and herd). This can only be explained by the change in behaviour of the virus because of genetic mutations popularly called a “double mutant “! The government authorities have denied this to be the cause of this surge. However, government’s claim needs to be critically addressed. The government has set up Indian SARS-Cov2 Consortium on Genomics (INSACOG ) in December 2020 specifically for genomic sequencing of the virus. The present behaviour of the virus in India is very similar to the UK strain. This UK strain was found in 82% of case sample of over 800 cases studied in Punjab. Such a high number of this mutant strain has not been replicated in any other state. Whether this sample from Punjab was representative of general population is unclear. Government’s denial about the mutant strain to be the cause of the second wave stems from the fact that a very small number of tested samples from states other than Punjab were found to have a lineage from a mutant virus from UK, South Africa or Brazil. According to experts, it is necessary to study at least 5% of the total cases for genetic mutation to conclude anything about the role of mutation in a given situation. Each test costs about Rs 3,000 to Rs 5,000. Presently, no special funds have been allocated for this purpose. Moreover, the sates are sending very few samples for genetic testing to the INSACOG. States with the highest caseload like Maharashtra, Kerala and Karnataka have so far done poorly on this front by sending less than 0.5% samples for the survey. As a country, India has tested only 0.16% of total number of cases. It is critical to get more data on this front from INSACOG in order to take important preventive public health measures like tweaking the vaccine to cover these mutants!
(The writer is cardiologist, Kamalnayan Bajaj Hospital, Aurangabad).