There is a glimmer of hope that corona testing in Indonesia can be improved. One solution currently being tried is to use an antigen-based test.
“Rapid test This high quality will show us where the virus is hiding, and this is the key to tracing and isolating contacts so that it can break the chain of transmission, “said WHO Director General Tedros. Adhanom Ghebreyesus, on the official WHO website.
To welcome the new corona test method, coil has summarized a number of things you need to know when doing a rapid antigen swab test. You can see it through the following list.
First of all, let’s discuss what antigens are. According to the explanation Eugene Wu from the University of Richmond, the antigen is the protein that triggers the antibody. The antigen itself stands for “antibody generator.”
Antibodies are protective proteins produced by the immune system in response to unknown proteins such as disease or toxins. This antibody has a shape like the letter Y, where the arm functions to bind to foreign proteins that are not recognized by the human body.
When a new disease appears, white blood cells will form new antibodies. In response to a new, unknown type of disease entering the body, antibodies change the shape of their traps in such a way as to match the binding of the disease proteins.
“The foreign protein that triggers this process is referred to as” anti-gene “because it is an antibody generator,” explains Wu in his writing at 9.
Well, as the name suggests, rapid test the antigen aims to detect the presence of the antigen in the sample of participants. In this case, rapid test The antigen is intended to detect the protein skin of the corona virus.
2. Rapid test antigen must be done by a specialist
Different from rapid test antibodies that can be done independently by ordinary people, rapid test antigens require the assistance of medical personnel. The reason is that the antigen test is similar to the PCR swab test in terms of sampling.
Rapid test the antigen begins with taking a sample from the nose or mouth. After the sample is taken, the medical staff will put the sample onto the surface of the test kit.
To process the sample, the antigen test kit requires two types of coronavirus antibodies. The first antibody functions as a ‘binder’ for the corona virus protein in the sample, if it turns out that the sample does have the virus.
3. It only takes 15-30 minutes
The ‘selling point’ of rapid test antigen is a process that does not need to take a long time. Generally, rapid test this antigen only takes 15-30 minutes to examine the sample to produce results.
When compared to the PCR swab test, rapid test antigen has a much simpler process.
As an illustration, the PCR swab test has many stages in the process. Because, it is different from the antigen you want detect through the surface of the skin, the PCR swab test aims to detect corona through genetic material in the sample.
The genetic material itself generally consists of DNA and RNA. Both of them are the carrying material of genetic information that every living thing has. The difference is, DNA is a double chain genetic material, while RNA is a single chain genetic material.
Because the corona virus is an RNA virus (ribonucleic acid), researchers need to convert viral RNA into DNA (deoxyribonucleic acid) so that it can be read on a PCR machine. To convert the corona virus RNA into DNA so that it could be analyzed by PCR machines, researchers used enzymes reverse-transcriptase.
According to the explanation of the United States Food and Drug Administration, the PCR machine will do the job amplification (propagation) millions of copies of DNA to read. If the PCR machine detects the presence of genetic material from the sample, the result will be said to be positive.
Due to the more process involved, the PCR test needs to take longer than that rapid test antigen. Generally, the PCR test only takes 2 hours to produce results. But, given that sample spread In the midst of insufficient laboratory capacity, PCR tests in Indonesia often give results 1-3 days after the test.
4. Need PCR swab test to confirm
Having a cheap price and a short time does not mean making rapid test antigen could shift the status of the PCR swab test as the gold standard for corona diagnostics. Because, accuracy rapid test the antigen is still under PCR.
Broadly speaking, there are two aspects of indicators in assessing the accuracy of a diagnostic test, namely sensitivity and specificity.
Sensitivity is the test’s ability to accurately detect the presence of the virus, if one is present. The less sensitive a test is, the more likely it is to give false-negatives.
As for specificity is the test’s ability to accurately rule out the presence of a virus in its absence. The less specific the test, the more likely it is to give a false-positive result.
In terms of accuracy, rapid test the antigen got specificity which is quite good in the 90s percent range. However, the sensitivity of this test is generally only around 50 percent, according to a Harvard Health report Publishing.
Hence, an antigen test is very possible show false-negative results, namely where people who are positive for corona are actually considered not infected with corona. To overcome this, medical personnel will recommend a negative person with an antigen test to do a PCR test, if the person has symptoms of the corona.
When compared to rapid test antigen, PCR has a much better level of accuracy.
Based on a study conducted by the non-profit research institute Foundation for Innovative New Diagnostics (FIND), the PCR test has a sensitivity of up to 100 percent and specificity 96 in a controlled environment.
However, in the real world the sensitivity of this test is only around 66-80 percent. This decrease was caused by a number of factors, ranging from the small number of samples taken to the low presence of the virus due to too fast or too slow test times.
5. There are only two newly recommended tools
So far, WHO has only recommended 2 tools rapid test antigen. Both are rapid test the antigen created by Abbott and SD Biosensor.
WHO also stated, provision rapid test antigen has been agreed upon by the Bill & Melinda Gates Foundation with the two test equipment manufacturers.