One of my relatives called me a few days back saying that she lost both taste and smell and was running temperature for the last few days. I suggested immediate home isolation and COVID testing. Her other family members also had fever simultaneously.
After giving nasopharyngeal and oropharyngeal samples for RAT and RT-PCR, she was found RAT negative immediately and it took three long days to get the RT-PCR report. In the meantime, an elderly member of her family, who had a fever initially, developed respiratory distress. When they were sure that they were suffering from COVID and preparing to isolate, the report of the pending RT-PCR was available and strangely it was COVID NEGATIVE! Thereafter, the family resumed living normally in society.
This is not an isolated event where a clinically COVID patient is tested negative via both PCR and RAT. To date, in our clinical settings, we do not yet know of any common disease which temporarily causes loss of taste and smell sensations simultaneously other than COVID. And since COVID 2nd wave, we are frequently getting the report of such incidents where patients are having COVID signs and symptoms, but RAT and RT-PCR tests are both negative. This is a grave problem because of the following new challenges:
The patient, until a repeat test of RT-PCR gets a positive COVID report, is treated symptomatically. By that time, we have already lost a significant amount of valuable time for the initiation of treatment. This is detrimental in many cases. Moreover, if clinical suspicion is not intense enough in milder cases, at times, a repeat test is not done and the patient continuously spreads the disease in the hospital settings as well as in the society after an incomplete recovery. As a result, healthcare workers, as well as common people, get infected. And these are among the greatest challenges for controlling the second wave of the pandemic other than the ASYMPTOMATIC COVID positive persons.
2. Once a family member is clinically suspected of having COVID symptoms but got a negative COVID report, the other family members are also reluctant & declining to test for COVID and thus continue spreading it in society. The impact of this is huge.
We know that RAT gets positive only when the SARS-CoV-2 viral load is high enough for its detection and naturally its sensitivity is lower than RT-PCR. This fact is accepted by all and we hugely depend on RT-PCR. But, during this second wave of COVID pandemic, the challenge is because of high RT-PCR negativity among the true COVID patients. Experts have identified two main reasons for it:
1. RT-PCR detects the virus based on a pre-captured genetic picture of the same virus. As the virus is getting mutated in multiple areas of its genetic format, the original genetic picture may be altered from the genetic sequences of the current SARS-CoV-2 and this false negativity is going to happen frequently.
2. The second reason is more challenging. It has been postulated that during the second ongoing wave of COVID pandemic, more and more people are suffering from COVID. In this wave, the SARS-CoV-2 virus is not harboring at the nasopharynx or oropharynx. As a result, both RAT and RT-PCR are giving negative reports.
3. Add to it the huge burden of testing samples and its Viral Transport Medium (VTM) which needs constant cold chain maintenance. If the chain gets interrupted anytime, RT-PCR results may be negative.
As anticipated, the second wave of the COVID pandemic is causing more challenges and lethality in our country. We need to understand the fact quickly and react as per the situation.
Best wishes to all.
