The mathematical model predicts around 60% of the population already exposed to the virus, which translates into herd immunity
Despite a recent outbreak of infections, India is unlikely to experience a “second wave” of infections, according to IIT, Kanpur deputy director Manindra Agrawal, also one of India’s leading mathematicians and among those involved in the national “Super Model” initiative, led by the Department of Science and Technology.
As on Friday, India has confirmed just over 11 million infections since March 2020, of which 1,52895 were active. Professor Agrawal said The Hindu Depending on the model, that number would reach a maximum of 11.3 or 11.5 million infections by April 2021 – or about 3.00,000-5.00,000 new confirmed infections over the next 10 weeks (approximately).
He and other scientists are working on a formal update to the model but were awaiting confirmed data on recoveries for the next two weeks, he said.
The current wave of infections – an average of 13,000 to 16,000 new confirmed infections per day since February 23 – was mostly led by Maharashtra and would not last beyond “two to three weeks” in March, he said. -he declares.
The reason, according to Professor Agrawal, is that around 60% of the Indian population had previously been exposed to the virus and the country had achieved herd immunity, or the number of susceptible individuals was too small to allow the virus to grow exponentially.
There is no question of whether the herd’s immunity levels have been achieved, as the Indian Council for Medical Research (ICMR) has reported that only 21% of Indians have been infected, according to its third national serological survey conducted. from December 17 to January 8, 2021. The Super Model estimate is about three times that number.
“ICMR numbers are based on the numbers in which antibodies have been detected. But we now know that antibody levels may decline, but are still sufficient to confer immunity. Given the slackening of movements for months, only an exposure of 20% can not explain the confirmed symptomatic infections, the active cases and the cures that we are currently seeing, ”he added.
In October, the “Super Model” initiative predicted India’s workload (of confirmed symptomatic infections) to reach 10.6 million infections with less than 40,000 active infections by the end of the month. from February. However, current active infections are nearly four times the model estimates.
Travel, soaring festivals
Prof Agrawal said the resumption of local train travel in Maharashtra and, as a result, increased contact between people was a reason for the surge in boom over the past week.
“There was a peak in Kerala because of the festivals and the increase in movement and it decreased. It seems to be a similar story in Maharashtra as well, ”he added.
COVID-19 was characterized by a large number of people who contracted the infection without showing any symptoms. In addition, those who showed even minimal symptoms would likely self-quarantine and limit contact with others. The mathematical model used, Prof Agrawal said, took these factors into account and therefore instilled confidence in its projections.
“Vaccines and the continued use of precautions are essential to continue this downward trend,” he added. The government has announced vaccinations for people over 45 with co-morbidities and those over 60 as of March 1.
Scientists have expressed skepticism about India’s collective immunity and point Manaus to Brazil. The city experienced a surge in April and by October 2020, local researchers estimated that three-quarters of the city had been exposed to the infection, conferring herd immunity. However, January 2021 saw a new resurgence.
In one Lancet study, scientists speculated that this could be because the actual number of people who contracted the virus in the first wave is overestimated, or the immunity is temporary and re-infections, as well as the exposure to new variants play a more important role. what is now expected. The ICMR has identified significant variants – such as the British variant, South African and Brazilian variants in India, but said recent peaks in Kerala or Maharashtra are unrelated to them.
Scientists at the Institute of Genomics and Integrative Biology reported a case of reinfection in a person from Andhra Pradesh on Friday. The patient carried a coronavirus mutation called N440K, identified last year in nearly a third of patients in the state and known to help the virus escape detection by antibodies to the immune system.