Constant monitoring is the only way India can build up its defences against new virus strains
In less than a month, it will be a year since India confirmed its first SARS-CoV-2 case in Kerala. From then and now, India looks infinitely more prepared in terms of testing capacity, vaccine candidates in development, public awareness and the kaleidoscopic experiences of those who have been exposed to the virus. However, the report of the new variant from the U.K. and confirmed in at least 25 travellers from there puts India back at the base of a new learning curve. First reported to WHO on December 14, the SARS-CoV-2 VUI 202012/01, or the ‘U.K. strain’, was detected only following an unexpected case spike in South East England. The U.K.’s consortium of labs periodically sequences 5%-10% of the entire genome of SARS-CoV-2 isolates from the population. From October 5 to December 13, over 50% of isolates were identified as the variant strain in South East England. This variant has at least 14 significant mutations, which could affect healthy cells or worsen compromised immune systems. Studies show that the virus variant, while not linked yet to increasing mortality, is more transmissible than other variants, thus indirectly contributing to a higher death toll. Even though the world has only now woken up to this variant, it may have been circulating in the U.K. as early as October, and with people flying on the U.K.-India route, it is quite likely that this may have already caused its circulation in India. This puts the country right back to January and February when attention was trained towards possible carriers from China and SE Asia, when it was travellers from West Asia and Europe who led to the case explosion after March. Then, India was just about figuring out how to mass produce and, more importantly, distribute RT-PCR kits and paraphernalia required for detection. Now, Indian scientists have to grapple with a new beast called mass genomic surveillance. For some years now, India has had genome sequencing machines and the personnel to track and identify new variants. However, like in the early days of RT-PCR, there are not enough of them to sequence the 4%-5% of isolates in the population like what the U.K. does. India has genome sequenced around 5,000 isolates compared to the U.K.’s 137,000.
That India has formed a consortium of leading genomics labs to make genome surveillance a routine continuous exercise is to be welcomed. With 2021 likely to be the year of the vaccine, with a rollout at an unprecedented scale, scientists have already warned that it is possible that some virus strains, or escape mutants, may change enough to evade the vaccine’s immune response — as observed in the case of hepatitis B. Therefore, continuous monitoring and developing suitable detection kits are the only way India can shore up its defences against this pandemic and those of the future.