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COVID-19 pandemic have reached each and every corner of the world. Initially we known there have Corona, but we ignored, because it was far from us, but now it reached here, we worried because it’s near to us. Day by day the infected cases are increasing in a geometric ratio and even a small sneeze now scares the people. The best tests are required for the people to know the accurate results, whether positive or not.
There are very tests are available for the diagnosis, the testing are done for mainly two categories, one is for virus and another is for the antibodies. We now have two main types of tests for COVID- 19 ; molecular and serological . The FDA has officially authorized over 30 manufacturers to make molecular tests, and over 10 manufacturers have been authorized to distribute serological tests.


In acute respiratory infections, molecular tests are routinely used to detect the presence of viral genetic material in a sample. The specific technique that’s used is called reverse transcription polymerase chain reaction, or RT-PCR, where genetic material from a sample is multiplied several times and then compared to the genetic sequence of the virus you’re trying to detect .Molecular tests typically involve inserting a 6-inch long swab into the back of the nasal passage through one nostril and rotating the swab several times for 15 seconds. This process is then repeated through the other nostril. The swab is then inserted into a container and sent to a lab for testing. The test is also can be done through throat.
The FDA has now authorized at-home collection molecular test kits, including those using nasal swabs or saliva for sample collection. A study done by the United Health Group suggests that the self-collected swab tests are similar in result accuracy as that of provide - collected swab tests.


 Molecular rapid test is known as most specific test ,take much time to get results than serology test .Most RT-PCR tests can take anywhere from a few hours to a few days, but new rapid diagnostic tests for COVID-19 show promise of results in less than an hour.
In case of accuracy, there is limitations in every tests. Molecular tests often found to be telling the accurate results, even though there’s a small chance that it could be a false positive, meaning that the test is positive, but you actually don’t have a COVID-19 infection. Like that there is chance for false negative too. A negative result with the molecular test means that the virus that causes COVID-19 was not found in the sample above the limit of detection, but it is still possible to have very low levels of the virus in the body. This all depends on the time when we take the test, if we took test too early or too late there is chances for false results.


Serological test are much easier and cheapest test compared to that of molecular test. In which     we detecting antibodies in a blood sample, usually obtained through a simple finger prick. These tests do not require special equipment to process the results, which allows them to be used in laboratories or at point-of-care.  Unlike molecular tests, serological tests can identify people who were infected and have recovered. 


Serological test is not much reliable or accurate as that of the molecular test, it’s more chance to be for false positive and false negative to it. When a virus infected to our body, and our body detected the foreign body it soon develops antibodies, which can take several days to over a week. Antibodies are proteins your body makes when mounting a response against invading germs. The presence of immunoglobulin M (IgM) antibodies indicate recent exposure to COVID-19, while the presence of immunoglobulin G (IgG) antibodies indicate later-stage infection. The rapid response serological tests typically use a technique called enzyme-linked immunological assay (ELISA), which detects the presence of these antibodies to the corona virus.
It may take several days to week to produce antibodies in our body   , so the results have much chance to be inaccurate, it may give negative results if the person actually caught the infection. The serological test is much faster than that of molecular test.
There are not promises that one who recovered to have a reinfection or not have an infection again. So be careful of ourselves and be safe.

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