More rapid antigen tests, fewer ‘gold standard’ RT-PCR tests mark fall in UP’s COVID numbers
Meerut: The COVID-19 numbers from Uttar Pradesh are encouraging — the positivity rate is down to 0.08 per cent from 22 per cent a month back.
There has been a surge in testing as well — a record 3,58,407 tests were conducted on Thursday, 27 May. These records are being made very frequently as previous “record” tests (3,58,273) were conducted just two days back on 25 May.
However, this is just one half of the story.
The other half of the story is that RT-PCR tests, the gold standard for COVID-19 testing, are less than half of total tests. The lesser accurate rapid antigen tests (RATs) are behind record numbers.
On 26 May, out of 3,47,821 tests in UP, only around 1.6 lakh were RT-PCRs — less than half. The rest were RATs, which are being conducted mostly in rural areas where the government is focusing after the ongoing second wave wreaked havoc there.
States were pulled up for fewer RT-PCRs
In November, a number of states were criticised for low proportion of RT-PCR tests.
This was around the time Centre intervened in Delhi following a surge in infections. The state was also in focus for low RT-PCR tests, with figures showing 70 per cent tests being RATs.
Other states were on similar lines — percentage of RATs in Telangana (90), Bihar (88), Uttar Pradesh (60), and Kerala (60) was either worse than Delhi or close.
Centre suggested RT-PCRs, emphasised RATs in U-turn, and numbers fell
Such an approach is contrary to what Prime Minister Narendra Modi outlined last month.
At a Centre-states meeting, Modi asked states to ensure that at least 70 per cent tests are RT-PCRs.
On another occasion, Union Health Secretary Rajesh Bhushan said RT-PCR tests should ideally be 70 per cent, but this was overridden by his own ministry in May that emphasised on RATs. The aspirational threshold for RT-PCR tests was reduced to 40 per cent from Modi’s and Bhushan’s 70 per cent.
Indian Council of Medical Research chief Balram Bhargava said the Centre projects around 45 lakh tests a day by June-end, out of which RATs would be around 60 per cent and RT-PCRs 40 per cent.
More RATs, falling positivity rate
Through a surge in RATs, Uttar Pradesh now boasts the highest number of tests in the country, writes Aman Sharma for Moneycontrol.
He further highlights this rise in RATs has coincided with a sharp fall in numbers — from a high of around 38,000 in April to less than 10,000 by the third week of May.
Why are more RATs, fewer RT-PCRs a concern?
Rapid antigen tests are known to have a false negative rate of up to 50–60 per cent, which means around half of those tested may get a negative result even when they are positive. In contrast, the false negative rate for RT-PCR tests is just 5 per cent as per ICMR, which is well within acceptable parameters. No test is 100 per cent accurate.
I can attest to this. In my family of six, only my father tested positive in a rapid antigen test. Rest of us had negative RATs but positive RT-PCRs.
This is a counter-productive exercise as people who are actually positive would come under a false sense of security after testing negative in RATs and they would continue to spread the virus to whoever they’d engage with. This would lead to a silent, untraced undercurrent of viral spread in areas where RATs are preferred over RT-PCRs.
Despite this, the UP government has focused on RATs over RT-PCRs in the hinterland. The reasoning is to increase coverage and prefer speed over accuracy as RT-PCR results may take up to two days but RATs produce on-the-spot results.
While results are quicker, the silent spread in the hinterland would go undetected because of lesser accuracy, leading to a fall in numbers and good publicity on social media but a worrying scenario in the hinterland.
The powers-that-be ought to imbibe PM Modi’s words. In April, he said states should not worry about numbers and their only worry should be testing and treatment.
He said, “I told you that you shouldn’t worry a bit if the number of cases is high. Don’t be under any kind of pressure that your performance is bad because your numbers are high. You just focus on testing, I’m telling you even now. There is no reason to think you are doing badly if your numbers are high. There will be more positive cases if you do more testing.”
Test-trace-treat was the mantra early in the first wave that I personally saw. Government healthcare workers have camped on my street in Meerut three times and have carried out twice as many screenings since last year. But that does not seem to be the case any more where a misguided approach with more RATs and fewer RT-PCRs is being taken. This needs a course correction.
The opinions expressed towards the end are personal. Numbers and facts, wherever mentioned, are attributed with hyperlinks.
This is a personal newsblog and it has no links, financial or otherwise, with any organisation or individuals.
I tweet at @madhur_mrt.
