COVID-19 antigen test in saliva: the steps to follow to do it correctly

A study carried out by the University of Cape Town, in South Africa, has concluded that saliva tests for COVID-19 are the most effective tests to detect the new omicron variant of the coronavirus.

In the study, which compared tests from 382 infected patients, saliva tests detected the coronavirus 71% of the time, while nasal samples did so 100%. In contrast, with omicron patients, saliva samples detected the virus 100% of the time. We explain how to correctly perform a COVID-19 saliva test:

-Do not eat food before the testa: It is recommended that no food or drinks be consumed for at least 10 minutes before performing the test so that they do not interfere with the test result.

-Hand disinfections: Thorough hand disinfection is required to prevent tests from malfunctioning.

-Cough: It is necessary to cough forcefully five times before spitting to collect mucus from the airways.

-To spit: next we must spit the sputum into the mouthpiece until reaching the control line of the container and proceed to mix the sample with the solution in the tube.

-Stir the mixture: Finally, we will close the sample tube with the dropper cap and shake it repeatedly -about 20 times- to mix both liquids well. Finally we will add 3 drops in the hole of the reactive plate. Once deposited, we must wait about 15-20 minutes to obtain the result.

-Results: the results are interpreted as follows: if the T line appears, the result will be positive, even if the line appears very faint. The line C (Control) must always appear, otherwise the test will not have been carried out correctly. If the 20 minutes have passed and only line C (control) appears, the result will be negative.

In the case of testing positive, the next step would be isolate ourselves and call our usual doctor to show us the steps to follow.

According to AEMPS, “self-diagnosis tests will not be considered for the confirmation diagnosis of active infection neither in people with symptoms nor in asymptomatic people” but that the positive results of these tests “will be considered suspicious cases that must be confirmed in a health center by means of a PDIA”.

In the event that we test negative, but we have been in close contact or even if we have symptoms, It is important to exercise some caution and in any case, continue with the security measures.