Again, the Covid-19 Tests

We know there are tons of information about the tests and are super tired of them, as well as everything related to this virus. 

However, we read this article about the subject, which we found very enlightening and well summarized.

Hoping not to bore you, here it is:

Rapid tests for covid-19: what are the differences?

The so-called rapid tests for COVID-19 have joined those we have known since the first wave of the disease, who need special equipment and laboratories, which are:

  • PCR (polymerase chain reaction) tests or molecular tests, which search for ribonucleic acid (RNA) in the SARS-CoV-2 virus genome and tell us, in an appropriate clinical and epidemiological context, if there is, at the time of carrying out the test, a SARS-CoV-2 infection;
  • Serological tests, which look for antibodies to the virus, and tell us whether there was an exposure to SARS-CoV-2 that our immune system tried to fight by producing antibodies, whether or not we had symptoms of the disease.

What are rapid tests?

Rapid tests are those whose results are obtained in a short period, usually minutes, and which do not need to be processed in a laboratory with specific equipment. Sometimes they are even carried out on the spot where the sample is taken. The best-known rapid tests are home pregnancy tests. 

Rapid tests for COVID-19:

  • Rapid diagnostic tests, which aim to identify, in an appropriate clinical and epidemiological context, whether the virus is present in the organism when they are performed;
  • Rapid antibody tests, which aim to identify whether there has been previous exposure to the virus and the body has developed antibodies.

This article is about the first ones mentioned above, that is, the rapid diagnostic tests.

The results of these tests interpreted in an appropriate clinical and epidemiological context, tell us if there is an active infection. They search for the presence of the virus, but do it differently from PCR tests:

  • The rapid diagnostic tests for COVID-19 currently available for use on a large scale, screen for virus-specific proteins. These proteins on the surface of the virus are the viral antigen (which induces the immune response), so rapid tests are also known as antigen tests;

Tests that detect the SARS-CoV-2 antigen can even be performed at the same location where samples are taken and their results are available more quickly than PCR tests, which are performed in the laboratory and require special equipment.

The technology that rapid tests use and the fact that they do not require laboratory processing make them much cheaper than the PCR tests available today.

The samples for the rapid tests of COVID-19 are globally similar to those for the PCR tests: nasopharyngeal exudates obtained with a nasal and/or oral swab. (…)”

Dr. Betânia Ferreira

Excerpt of the article of Doctor Betânia Ferreira Internal Medicine, Hospital da Luz, on April 29, 2021

And, be careful with your nose 😉 #BeSafe

Até já!

Please, leave your comment.

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s