The Capital recorded the highest single-day spike of new coronavirus disease (Covid-19) cases on Saturday, even as the Delhi government kept up its ramped testing numbers. The city recorded 4,321 cases of the viral infection in 24 hours, according to Saturday’s health bulletin.

Delhi also recorded the highest-ever total hospitalisations on Saturday, with 6,294 people across the people admitted to hospitals with the infection. The highest number of hospitalisations recorded during the June-July surge was 6,264, after which the number of cases and hospitalisations gradually declined.

With the increase in cases over the past few days, the city has seen a concurrent increase in the number of active cases. As on Saturday, there were 28,059 active cases in the city, nearing the June 27 high, when 28,329 people were still fighting the infection.

However, the increase in new infections came after the city kept up its high test rate on Saturday. Over 60,000 tests were conducted in the city for the second day in a row, with hospitals and mohalla clinics testing several asymptomatic persons.

The positivity rate — the fraction of people who test positive among those tested — reduced to 7.19%, as compared to an average of 7.92% recorded in the previous seven days, and 8.98% the week before.

However, the number of RT-PCR tests continued to remain low, and were far less than the number of less-sensitive antigen tests conducted. Only 9,182 samples — 15% of all tests — were conducted using the RT-PCR method, considered the most reliable for the diagnosis of the disease.

“The number of cases in the city are now slowly stabilising – we have been recording about 4,000 cases a day with 60,000 tests. When the city had last seen 3,900 cases, there were only about 15,000 tests being performed in a day. The increased testing by the government will ensure that more and more people are isolated early on thereby preventing further spread of the infection,” said Dr SK Sarin, director of Institute of Liver and Biliary Sciences (ILBS) and one of the heads of the first committee set up by the Delhi government to tackle the infection in the city.

“The Delhi model is a great one where hospitals — even non-Covid-19 ones — are testing patients coming in to routine OPD for other ailments along with some of their family members. This helps in detecting several asymptomatic cases. My only concern now is that the city should do more RT-PCR test and the capacity to perform the test must also be scaled up,” said Dr Sarin.