It is a critical question some people are discussing in the social media. What is the reality ? We are trying to collect information into one.
What is an RT-PCR test?
RT-PCR stands for Reverse Transcriptase Polymerase Chain Reaction. Simply this is a PCR test done to identify particular RNA strand. In a case like COVID-19 where the disease is caused by an RNA virus first the RNA strands from the viral samples are extracted inside a laboratory and converted in to DNA using the Reverse Transcriptase enzyme. Then these DNA samples are subjected to a PCR reaction. In this test special probes are used to detect specific regions within the genome of SARS-Cov2. For an example the test kit prepared according to the CDC guidelines use N1 and N2 regions.
How many labs in Sri Lanka are now working on Corona testing?
Currently as of 3rd April, there are 10 laboratories working on the corona testing. 3 more labs will join next week.
How many tests done a day ?
200 – 250 tests a day. That includes new suspected cases and current patients who are getting cured.
What is the current capacity of tests?
800 to 1000 tests possible per day collectively.
Why don’t we test all people ?
It is not necessary to test all people. there are some criterion for recruiting suspected cases for testing. CDC of US and WHO has given some basic guidelines on this. Health officials are evaluating the testing policy and sooner they will declare the community testing policy.
Are enough testing materials available?
This is a critical situation where the whole world is demanding. So many test kits are being sold. Some are good and some are bad. Good products are evaluated and CDC issues approval for emergency use. Sri Lankan labs have been using CDC approved test kits since beginning of this COVID-19 issue. As per the information, more than 1000 tests are available per day if required. Currently more than 15000 tests are available and orders scheduled well.
Do we manufacture test kits ?
No. We do not manufacture RT PCR test kits as yet. There are some initiatives but there isn’t a good commercial background in Sri Lanka to have a profitable test kit production. Production of a good reliable test kit needs lot of areas of expertise and capacity. That should be strengthened to be self sustained. Those who are already engaged in the import and distribution should join with scientific bodies and government should fund the initiatives transparently.
What do we test right now?
CDC or the Centers for the Disease Control and Prevention of United States is one of the main institutes that check and approve the disease test kits and protocols. From the begining Sri Lanka used CDC approved protocols and CDC approved test assays developed by IDT DNA technologies to test and identify COVID-19. CDC authorized IDT DNA Technologies assays detect three gene targets in one test and therefore higher in sensitivity. IDT offers primers and probes for the N1, N2 and RP assays and positive controls.
More information is available https://sg.idtdna.com/…/landi…/coronavirus-research-reagents
These are the most widely used targets in the coronavirus testing. In addition to N regions there are test kits that use other targets like E, S and RdRP genes.
Can’t we use rapid test kits ?
Rapid test kits use completely different approach to test an infection, instead of detecting DNA or RNA of the infectious agent these rapid test kits detect antibodies produced by the immune system against the disease causing organism. But unfortunately, so far, these rapid IgG IgM antibody tests have have shown very little sensitivity. Globally some Chinese companies have been banned for selling rapid tests that can not give even 20% sensitivity. Genetic testing is the best method to have a better sensitivity. There are branded good machines to use gene testing but global demand has made it difficult to sell in Asia. If those machines are purchased, continuous dedicated test kits can not be delivered to this area of the world.
Antibody tests will be used in the future for surveillance needs.
Airlines are demanding RT-PRT test results to prove you are Covid-free.
Where in Colombo can a private person get these tests done???
Thank you for a reply.