Onset of fourth wave? In Delhi, every Covid-19 positive person infected two others this week

New Delhi: Amid the rising Covid-19 cases in Delhi, an analysis by IIT-Madras has revealed that every infected person is infecting two others in the national capital. 

According to the PTI news agency, Delhi's R-value or reproductive value, which indicates the number of people an infected person can spread the disease to, was recorded at 2.1 this week. A pandemic is considered to end if this value goes below one. 

The preliminary analysis by computational modelling was done by IIT-Madras' Department of Mathematics and Centre of Excellence for Computational Mathematics and Data Science headed by Prof Neelesh S Upadhye and Prof S Sundar.

The analysis also found that India's R-value, at present, stands at 1.3.

Asked if it can be deduced that this is the beginning of the fourth wave of Covid-19 in Delhi, Dr Jayant Jha, Assistant Professor, Department of Mathematics, IIT-Madras, said it would be too early to declare an onset of another wave.

"We can only say right now that every person is affecting two others....But we need to wait a bit to declare onset...We don't know about the immunity status and whether the people who got affected during the third wave in January are getting affected or not again," he told PTI.

For other metro cities -- Mumbai, Chennai and Kolkata, Jha said the number of cases is too low to ascertain a trend.

Delhi, which is currently witnessing an uptick in the number of Covid-19 cases from the past few days, logged 1,042 new coronavirus infections with a positivity rate of 4.64 per cent on Friday.

As per reports, the Omicron sub-lineage BA.2.12 has been detected in a majority of the samples sequenced from Delhi in the first fortnight of April and it could be behind the recent surge in Covid-19 cases in the city. 

Media reports have also claimed that Omicron variant derivative BA.2.12.1 has been found in a few samples in Delhi which are said to be contributing to the recent rise in cases in the US. Officials, however, have not confirmed that it indeed was found in some samples in Delhi.

(With agency inputs)