With the number of people under surveillance in Kerala growing exponentially with each passing day and the number tested for COVID-19 lagging far behind, Kerala has decided to go for rapid testing in a big way.
Health minister K K Shailaja on Sunday confirmed that ICMR (Indian Council of Medical Research) had given Kerala its approval to begin rapid tests.
While on an average 25,000 people are put under observation each day Kerala, Kerala has been able to publish the results of just about 400 samples a day. This has left an ever-swelling pool of untested potential COVID-19 cases in the community.
This has allowed the uncertainty level to remain proportionately high, and grow with each day. Over 99 per cent of those under surveillance in Kerala are quarantined in homes and their swabs taken only if they show severe symptoms. Since the virus might take even up to 12 days to show up in the form of fever or cough, the chances of a deceptively normal virus carrier infecting at least those within the family are alarmingly high.
This is where the rapid tests could be of help. With these tests, more than double the number of people could be tested for the virus on a daily basis and, once found positive, could be promptly isolated in hospitals. “This will go a long way in preventing the community transmission of the virus,” Shailaja said.
It's time to worry about doctors
Also ignored are the clear and present danger to health workers; doctors and paramedics who work closely with COVID-19 patients. Their samples, like in the case of others, are tested only if they show symptoms. “What if some have already been infected and have still not shown any signs? In this highly chaotic and desperate situation, where shortage of trained staff is a big worry, they keep on functioning until their coughs turn persistent and noticeable,” a top health official said.
Rapid tests will now be used to keep a close tab on the status of health workers. “Now if one health worker in a COVID Care unit tests positive, a highly likely scenario given how close they are to patients and the inadequate protective gear they wear, we have to isolate the entire medical staff. If we continue to ignore the risks to health workers, this can possibly lead to a situation where COVID Care centres are gradually emptied out of doctors and paramedics,” the health official said.
Besides health workers, the plan is to conduct rapid tests on other high-risk cases; namely, those who had returned from foreign countries, their primary contacts, and people whom doctors consider suspect. The government also plans to use rapid tests in places from where more than ordinary number of respiratory diseases, especially viral pneumonia, are reported this season.
Non-confirmatory but useful
To be employed are rapid test kits that have the sanction of ICMR and Pune Institute of Virology, the health minister said. Nonetheless, rapid tests are not as conclusive as the tests that are being conducted confirm COVID-19. In other words, it is not a confirmatory test.
ICMR itself has said that a negative result did not rule out COVID-19 infection. To confirm the presence of the virus, the two-stage COVID-19 testing has to be done.
Rapid tests, therefore, can only be a preliminary selection exercise that can allow health authorities to map the extent of the virus spread.
High speed, low cost
It is the speed of the results that makes rapid tests a necessary tool in the fight against COVID-19. If the usual tests done in approved labs takes a minimum of two days to provide results, rapid test kits would give out the results in 30 minutes. It can also be done on more people, say 1000 a day. Quarantining, therefore, can be made more effective.
Called the antibody test, it is a simple test that scouts for the presence of antibodies in the blood. While the COVID-19 tests uses a nasal or throat swab, a rapid test requires blood or serum or plasma samples.
Any body infected by a virus will produce antibodies to fight the foreign presence. If antibodies are present in the blood, it is a sign of the presence of Sars-CoV-2.
Most importantly, costs are also said to be refreshingly low. A source said a kit would cost less that Rs 400. The usual elaborate two-stage COVID-19 test will cost Rs 3,500 per person.
There is but a minor glitch. Since the antibody persists in the blood even after the infection has been cured, these tests can show up as positive even in the samples of those who had recovered.