What is behind the false-negative RT-PCR Covid tests?
Kolkata, India: Lying on the bed desolate with uncertainty, Kabir could not connect the two dots: he was sick, had symptoms widely regarded as that of COVID-19, but the RT-PCR test he had done recently came negative.
After five days, Kabir's condition worsened, and he went for another test. That had come positive. Kabir is now in ICU, undergoing treatment for aggravated COVD-19 symptoms.
Perhaps his treatment could have been better should his first test came truly positive.
This has increasingly been a trend in recent weeks, as more and more people in India are having to get themselves tested for the virus. India is in difficult waters as it battles a dreadful return of the pandemic.
Healthcare infrastructure is crippling, frontline health staff are being pushed to the brink of collapse with the pressure of new cases. Add-on to the difficulties comes the issue of false-negative testing.
Tonnes of cases of false negatives are surfacing from across Indian, especially in cities where the caseload is high.
People feel sick, exhausted and COVID-ish, they get tested that turns out negative, and then they get tested again after some time when symptoms persist, only to find a positive result, with the conditions worsened.
But why are so many cases of false negatives surfacing?
RT-PCR or reverse transcriptions polymers chain reaction is considered a 'gold-standard when it comes to testing for COVID-19, but why the contradictory performance in real-life?
Before we delve deeper into what causes the false-negative with the RT-PCR test, let us understand what is a false-negative in lab tests.
What is a false negative test?
One of the principal ways of containing the spread of the virus is testing for the same. But in doing so, the accurate results can be hampered thanks to the potential of false negatives.
In medical terms, a false negative test result means the test will erroneously label the person as not infected while in reality, the person might be.
Hence, it is understandable, a false negative is more consequential than a false positive that erroneously labels someone as infected.
The reason why a false-negative test could be more harmful because infected people -- even if they are asymptomatic -- may not be isolated and can infect others.
Why are so many RT-PCR tests turning out false negative?
The most reliable method of COVID-19 testing is RT-PCR or Reverse Transcription Polymerase Chain Reaction. However, it may also produce false-negative results.
According to many media reports, the rapidly mutating novel coronavirus is breaching the test's mechanisms hence turning around the false positive.
Addressing the claim, the Indian government assured that the RT-PCR tests do not miss out on the "UK, Brazil, South Africa and the Double Mutant" strains of the novel coronavirus.
Reiterating the same notion, Dr. Gangakedkar an internationally reputed epidemiologist said that there is currently no data or analysis anywhere in the world that shows any variant evolving enough to beat the RT-PCR test.
However, there is enough evidence to suggest that poor swabbing and sample collection may have an effect on testing, he said.
Another expert, who's a professor of biosciences at the Ashoka University said he is worried because many people who are heading for swab collection are not properly trained and this is of worry.
Further, explaining the science behind the false-negative, Dr. Gangakedar told News 18 that timing is essential to prevent false-negative results.
If the swab tests are conducted too early or too late in the infection cycle, could favor the false negatives.
But does that mean false negatives in this second wave are overwhelming the healthcare industry?
According to a medical consultant based in Mumbai, Dr. Trupti Gilada, they're encountering false negatives in this second wave, on par with the first wave.
She told News 18, "We know the RT-PCR test will miss 30% of the cases, and that is how it is playing out."
In reality, the new mutant variant of the novel coronavirus is responsible for 60 percent of cases in Maharashtra.
How would our positivity levels be as high as 20% if it had evolved a mechanism to beat the RT-PCR?” she inquired.
Hence, the issue of false-negative could be rooted in more than one reason.
India COVID-19: A dreaded scenario unfolding
The world's second-biggest nation in terms of population is now amid a draconian crisis of a skyrocketing second wave pandemic.
The virus has spread faster than the first wave, but the country, unfortunately, is not better equipped to handle the same as history repeats itself.
The crisis is unfolding from every corner of the country, starting from vaccine shortfall, shortage of critical drugs, oxygen to hospital beds.
Calls after calls for beds are being denied, as patients lie in corridors and outskirts of healthcare centers. Several have died waiting for the hospital admission.
COVID-19 testing centers in cities are rejecting dozens of requests, as they are pushed to the brink of their capacity.
"We're seeing an unprecedented surge in the number of COVID-19 test requests we're receiving daily," says Deb Lahiri, who runs a unit of the COVID-19 testing clinic in Kolkata.
"Last year in June-July, the numbers of COVID-test query were high, which diminished by the end of last year. But from March, we're again starting to see overwhelming requests daily in Kolkata," Mr. Lahiri told We The World Magazine.
He said although he feels a moral obligation to test for as many people as possible, nonetheless, he's having to refuse dozens daily because of their limited capacity.
For every one call, Mr. Lahiri took during We The World's visit to his center, he showed two missed calls on an average hitting his call log while he attended on call --- such is the rush in Kolkata.
The situation is worse in other metros like Mumbai, Delhi, Bangalore, and others.
Scenes outside the hospitals across the Indian cities paint a grim picture, many reminiscences to the ones in Italy and New York during the first wave of the pandemic.
But in the land of 1.3 billion, it seems like things are under control. Despite the outburst of the virus, India has struggled to contain the spread and its people.
Media scenes from the public hotspots across the nations show a bustling picture -- as if the nation has defeated the virus, whereas the truth is far from it.
Behind the buzz in the markets, enthusiasm in the fully operational gyms and other places dotted with the crowd, no one is caring about maintaining proper social distancing, many are without wearing masks.
The government as well as the public appears to be rather casual when some of the nation's biggest public gatherings take place, like in the festival of Holi, the massive Kumbh Mela, and currently the General Assembly Elections in five states.
THOUSANDS GATHER TO CELEBRATE HOLI - THE FESTIVAL OF COLOR IN THE INDIAN CITY OF MATHURA WITH NO SOCIAL DISTANCING AND MASK-WEARING IN PLACE, AS PANDEMIC KILL HUNDREDS DAILY IN INDIA - SECOND-WORST HIT IN THE WORLD(IMAGE COURTESY OF RAVI SHARMA VIA UNSPLASH)
Experts opine several ways to manage the spread, including ramping up the vaccination, incurring strict lockdown in limited time, and curbing social gatherings.
But in both domains, India is struggling to keep up. So far only 100 million doses of vaccine have been deployed, in a nation of over 1.3 billion.
Successful control lessons from Israel and the UK call for at least 40% of the population to be vaccinated to bring the spread to a basic level, which in India's case is far away.