Given how the pandemic threw life off-gear in the last two years, reports of daily new Covid-19 cases in India falling to below 1,000 for the first time since April 20, 2020, is a huge relief. Even the seven-day moving average has been showing a decline since end-March. There is no doubt that India has got to this stage on the back of monumental efforts on vaccination. Though there is still a long way to go, the fact that close to 1.9 billion doses have been administered in total, including 22 million booster doses, is a great achievement. While there is much cause for celebration, it should not lead to a hasty declaration of victory. India saw undue haste in chest-thumping just before the second wave. Daily new infections had been falling just before that surge and had triggered a misplaced optimism that India may have passed the worst. This led to dropping the guard on mask usage and social distancing even as the country’s vaccination drive was yet to kick off, as data from the Institute of Health Metrics Evaluation showed. There have been signs of such declarations of victory following the receding of the Omicron wave. Thankfully, the last surge, in January this year, was led by Omicron sub-types that were highly infective but less virulent. It didn’t, therefore, overwhelm us with the number of cases needing hospitalisation. What, of course, also helped was the rapid progress in vaccination coverage and the natural immunity developed from exposure to the disease, as evident from serosurveys.
However, antibody protection against SARS CoV-2—whether from vaccines or exposure to the virus—will likely wane within months, according to scientific consensus. Also, there is no predicting how the virus will mutate. Even as the World Health Organization says studies are underway to determine the virulence of the Delta-Omicron recombinant, the Mumbai municipal body on Wednesday said that a Omicron sub-type, XE, that is more infective than the parent strain may have been detected in a patient in Mumbai. The Centre has rejected this on the basis of what has been reported as “preliminary assessment”, even as results of confirmatory tests will take time. The XE variant is understood to mirror its parent strain’s low virulence, but some caution would perhaps be in order. Many Asian countries are now battling resurgence and are contemplating restrictions that their economies can ill afford. The need now is to open booster doses across age groups instead of restricting it to just senior citizens (just 12.3 million such doses have been registered so far). The immune-compromised need immediate booster doses as the protection from earlier doses will diminish over time. An ICMR-RMRC study in September last year posited that the antibody levels starts to decline in recipients of Covaxin and Covishield after two and three months, respectively, of a shot. The gap of 39-weeks between the second and the booster doses that the government has set also needs a rethink—a study published in The Lancet held that a third dose of Covishield given at least six months after a second dose, boosted antibody levels six fold and maintained T-cell response.
The contesting XE claims from BMC and the Centre shows that the governments—the Centre, states and local bodies—need to be clear and unequivocal in communicating risks to the masses. This will require an expansion of tracking capacity and rigour. The masses will need to be reminded at every turn about continued behavioural caution. Vaccine penetration is still slow in populous African nations, as data from Bloomberg shows, leaving a large enough immune-compromised population for the virus to evolve in unpredictable ways. To expand vaccination and tracking new variants are the only real ways forward.
