NEW DELHI: Going by recent numbers, the Delhi government is more inclined towards conducting Rapid Antigen Tests (RAT) than RT-PCR tests in the city.
Only 1,365 cases out of over 2.62 lakh residents who undertook RATs were made to go for an RT-PCR test again, of which 243 tested positive, according to the state health department’s response to a high court hearing.
Responding to a petition filed by advocate Rakesh Malhotra, the Delhi government said that from June 18 till July 15, the state had conducted 2,81,555 RATs of which 19,480 came positive.
Amongst those who undertook RAT, only 1,365 were followed up with an RT-PCR test of which 243 again tested positive.
Following the meeting with the Ministry of Home Affairs, the Delhi government ramped up its testing from June 18 onwards by introducing RAT.
So far, the South-West district conducted the highest number of RAT tests which is 39,804 followed by the North district where 32,332 residents were taken for the same test. The lowest is from the South district which is 16,421 RAT tests.
RT PCR tests are conducted among individuals with symptoms consistent with influenza-like illness (ILI), that have otherwise been reported negative by RAT. This is done as RATs have moderate sensitivity and may give false-negative results in some cases.
The Delhi government has adopted a test, track and treat strategy and has also introduced RAT facility at polyclinics and dispensaries for the first half of the day.
In an affidavit, ICMR stated that the research body under the central government had received a request from 450 applicants from private hospitals and laboratories in Delhi for seeking authorization to conduct the RAT test, out of which 150 applications have been allowed and 300 applications are pending on account of certain procedural formalities required to be completed by the applicants.
According to the state government, the authorities on July 11 had also mailed the NCDC seeking a sero surveillance report but that has not been provided yet.
Why RT-PCR is necessary
RT-PCR tests are conducted among individuals with symptoms consistent with influenza-like illness (ILI), that have otherwise been reported negative by RAT.
This is done as RATs have moderate sensitivity and may give false-negative results in some cases.