Test results may still be negative despite one having COVID, experts warn. According to them, those showing symptoms must be treated without waiting for a confirmatory test to prevent aggravation, as per PTI.?
There are many cases where patients showed COVID symptoms but tested negative on several occasions. After repeated testing, they were found to be positive, said doctors.
The general perception of the experts now is that a high degree of suspicion arising out of the clinical symptomatology and the CT scan reports should be the guiding factor for treatment rather than relying only on the RT-PCR test which has a sensitivity of only 70 per cent, Dr Neeraj Gupta, professor in the Department of Pulmonary, Critical Care and Sleep Medicine at the Safdarjung Hospital in Delhi, said.?
Even the rapid antigen test has a sensitivity of only 40 per cent.?
"So many patients will be missed if we rely only upon these tests," Dr Gupta said.?
The antibody tests has a sensitivity of 90 per cent but they are only useful for confirming past exposure for SARS-CoV2 and have no value in the early stages of the disease.?
"All the treatment strategies should be guided towards preventing the progress of the disease from its mild to moderate or moderate to severe and for that we cannot wait on test reports. We have to go by clinical symptoms," he explained.?
Dr Vijay Gurjar, an assistant professor in the Department of Geriatric Medicine at AIIMS here, said there have been several instances where the patients tested negative even after three or four RT-PCR tests despite clinical presentations and CT scans indicating atypical pneumonia which is highly suggestive of Covid-19.?
Later on, they were found to have antibodies against coronavirus which means they had the infection but their results had not come out positive in the RT-PCR tests, he said?
"Thus, if patients have the symptoms, more so, if he or she is an elderly or has co-morbidities, they should be treated on the lines of Covid-19 and managed accordingly without waiting for the test confirmation," Dr Gurjar said.?
According to Dr Nikhil Modi, senior consultant of Respiratory, Critical care and Sleep Disorder at the Indraprastha Apollo Hospitals, New Delhi, one of the main reasons behind incorrect test results is the improper procedure of sample collection from the throat and the nose.?
"If the sample is not collected in a proper manner, then it may lead to incorrect results. Also the viral load plays an important role, as when low, the test results may come out negative even if the patient has the infection," Dr Modi said.?
"In cases where symptoms are highly suggestive of Covid-19 and the RT-PCR test continues to be negative even after repeated tests, a CT scan of the lungs can be useful in reaching a correct diagnosis," he elaborated.?
The AIIMS' Resident Doctors' Association recently had written to the ICMR seeking formation of an expert committee for provision of professional enquiry for the unexpected, unexplained deaths during the pandemic.?
A comprehensive diagnosis of Covid-19 verified by the expert committee involving clinical history, examination, imaging, biochemical, molecular testing and forensic investigations must be considered as cause of death in absence of an alternative diagnosis so as to help the bereaved families of the frontline healthcare workers to get compensation, it said.?
"This is to bring to your kind notice that many of the healthcare workers have lost their lives in the line of their duty in Covid-19 pandemic. As per the literature sensitivity of none of the tests performed for Covid-19 diagnosis is 100 per cent.?
"This has led to alleged misdiagnosis of some health workers who succumbed to Covid-19-like illness," the letter stated.
The AIIMS RDA mentioned the death of Dr Abhishek Bhayana, junior resident, from the department of Dental surgery at Maulana Azad Institute of Dental Sciences, New Delhi, who presented with symptoms of sore throat and breathlessness.?
The death summary clearly mentions manifestations consistent with Covid-19 but his test results had come out negative, the RDA said.?
Dr Gurjar said that major policies regarding compensation for corona warriors should not be decided just on the basis of microbiological reports.?
"The clinical presentation and other findings shouldn't be ignored.We should have a comprehensive approach for Covid-19. Timely response and intervention will definitely help in improving patient's outcomes with suspected Covid-19 clinical presentations," he said.?
According to AIIMS Director Dr Randeep Guleria, there is always a chance that it is a false negative.?
"If the test is not properly or a swab is done taken properly, it shall be a false negative. If the symptoms are there and you have been in contact with a COVID positive person, then you must assume you are COVID positive too and take the necessary steps as any patient would," he said while speaking to NDTV.?
Dr Anurag Agarwal, director of the National Institute of Biomedical Genomics said that while a positive person may test negative in the RT-PCR test, the reason is not the double mutant strain.?
"Double mutant was sequenced through PCR positive. So it is not possible that the mutant escapes the RT-PCR test. Then we could not have sequenced it," he said as per the Union health ministry, according to Hindustan Times.?
"What people should remember is that PCR has a sensitivity of 70 per cent. "The load of the virus in one's mouth and nose remains the highest a day before the symptoms start showing. Then the virus load gradually decreases. If people get tested late after 7 to 8 days, it is possible to get a negative test report because the virus may have travelled inside the body," he added.?
So the bottom line is this, if you test negative but still have symptoms then take the normal precautions as one would if one did test positive. Consult a doctor, do a retest and also isolate oneself.??
??