Just when India has started relaxing Covid-induced restrictions,   a team of Indian Institute of Technology (IIT) Kanpur, has warned that the fourth Covid wave might arrive in mid to late June. They said the surge is likely to continue for about 4 months — to be precise from around June 22 to be continued till October 24.

The IIT team has been quite accurate in their previous forecast about Covid-19 onset, with a deviation of only a few days

The severity, however, will depend on the emergence of the new variant, its nature, the vaccination status as well as administration of booster doses across the country, the IIT team said.

The statistical prediction was published on the preprint server MedRxiv on February 24. However, it is yet to be peer-reviewed. According to their paper, the curve will peak sometime around August 15 to 31 and decline thereafter.

Predictions by the researchers — Sabara Parshad Rajeshbhai, Subhra Sankar Dhar and Shalabh of the department of mathematics and statistics of IIT-K — used a statistical model and said the fourth wave in India may arrive 936 days after the initial available date of the Covid-19 outbreak which was January 30, 2020.

"Therefore, the fourth wave (presumed) starts from June 22, reaching its peak on August 23 and ending on October 24," they said. The team used a methodology called "bootstrap" to compute the confidence interval of the time point of the peak of a fourth wave," it said.

According to the researches, the method can also be used to forecast a fourth and other waves in other countries as well.

There is always a fair chance that a new variant of this virus may have an intense impact on the whole analysis. The intensity of the impact will depend on various factors like infectibility, fatality etc., the researchers  said

Apart from this fact, the effect of vaccinations - first, second or booster dosage--- may impact  on the possibility of infection, degree of infection, and various issues related to the fourth wave, they  added.

The researchers started working on the fourth wave prediction motivated by the accuracy of the third wave forecast done using a mixture of Gaussian distribution based on the data on Zimbabwe.

Another recent study has shown that the next Covid variant can emerge in two different ways. Also, there is no guarantee that the new variant will be less severe than the previously identified ones, they pointed out.