In a span of one week, eight people who had the coronavirus infection were wrongly tested negative at the Jayanagar General Hospital (GH) in Bengaluru, and two of them lost their lives, a Times of India report said.
The government-run hospital authorities claimed that the scale of false negatives in such a short span was unprecedented. The report quoted Dr Sudha Heroor, nodal officer for Covid-19 at the Jayanagar GH, as saying, “All eight cases had typical symptoms of Covid-19 and required admission. We conducted a CT scan in all these cases which showed the infection. However, we lost two patients.”
According to the report, Dr CN Manjunath, nodal officer for lab and testing, state Covid-19 task force, pointed that although this may not be representative of all positive cases, there are chances that these could be among a cluster of such false negatives.
Manjunath added that while around five to eight percent of tests across the state throw up false negatives, the syndromic approach of following it up with a CT scan is now well established.
Dr Satyanarayana Mysore, pulmonologist, recommended a CB-NAAT test immediately following an RT-PCR, in case the patient is symptomatic and the test result is negative. Mysore also said that false-negatives occur when the swab is taken on the ninth day after the person is infected or if the test is done long after the swab was collected.
However, the Chief Health Officer of the Bruhat Bengaluru Mahanagara Palike, Dr BK Vijendra, said that there was no increase in the number of RT-PCR false-negative cases.