Independent experts have criticised a recent modelling study from a group of researchers at the Indian Institute of Technology, Kanpur that predicts a fourth COVID wave in India around June.
The study, uploaded on the preprint server, Medrxiv, which hosts scientific work that is yet to be published in a peer-reviewed journal forecasts the wave to begin precisely on June 22, 2022, reaching its peak on August 23, 2022 and ending on October 24, 2022. For its analysis, it takes the trajectory of the coronavirus epidemic in Zimbabwe, because its history most resembles the case trend in India, and concludes that because Zimbabwe has seen a fourth wave, India is a fait accompli.
The authors, Sabara Parshad Rajeshbhai, Subhra Sankar Dhar and Shalabh, of the Department of Statistics and Mathematics, IIT-K, add caveats that the future wave could be affected by the nature of the existing variant that would emerge as well as vaccination coverage.
The Hindu could not immediately reach out to the authors for comment.
“The findings from this study are aimed to help and sensitise the people. For example, a few countries including the Government of India have started to provide booster dose to a section of people, which may reduce the impact of the fourth wave in a long run,” their paper notes.
A group at IIT Kanpur, led by Manindra Agrawal, a professor of mathematics and computer science, is behind the SUTRA model, whose forecasts on the pandemic are widely followed. While this model failed to forecast the deadly second wave and was critiqued by epidemiologists and biologists for its approach, it was accurate at gauging the trajectory of the third wave. The latest study is however independent of the SUTRA model.
Mr. Agrawal told The Hindu that he disagreed with the underlying assumptions of the latest study. The timing of a hypothetical fourth wave, he said, could not be predicted because it was heavily dependent on the nature of a future variant. “There is absolutely no way to predict the timing. If at all we see one, it will be very short and would have to be caused by a highly infectious variant because you have to account for the fact that nearly 90% of India has been exposed to the virus,” he said. The SUTRA model does not yet see a fourth wave, he added.
Gautam Menon, of the Ashoka University and who has been closely involved with efforts to mathematically model the pandemic argued in an explanatory Twitter thread that the forecast of a fourth wave “shouldn’t be taken seriously” because epidemiology wasn’t an exact science like physics or chemistry. The pandemic waves were being driven by variants, none of which could be predicted in advance, and modelling could at best be useful for “broad policy rather than a highly specific prediction of numbers.”
Zimbabwe’s median age was 19 as opposed to India’s 30 and had a vaccination coverage of 40% of the population to India’s 75%. These meant different degrees of “hybrid immunity” (that is protection from future infections due to a combination of vaccines and previous exposure) and the current study did not account for this rendering their predictions unusable, he opined. “Should one trust this model at all? The answer, simply, is no.”
- Independent experts have criticised a recent modelling study from a group of researchers at the Indian Institute of Technology, Kanpur that predicts a fourth COVID wave in India around June
- For its analysis, it takes the trajectory of the coronavirus epidemic in Zimbabwe, because its history most resembles the case trend in India, and concludes that because Zimbabwe has seen a fourth wave, India is a fait accompli.
- The authors, Sabara Parshad Rajeshbhai, Subhra Sankar Dhar and Shalabh, of the Department of Statistics and Mathematics, IIT-K, add caveats that the future wave could be affected by the nature of the existing variant that would emerge as well as vaccination coverage
