Scientists are currently discussing whether it is sufficient to detect an omicron infection using a nasal swab test. In the following article we will find out whether we need to test ourselves differently now.
Self-tests and quick tests have become indispensable in the corona pandemic. Especially now that the omicron wave is picking up speed, the rapid tests are making an important contribution to identifying infectious persons and suspected cases. So far, however, there are many unanswered questions regarding the rapid tests: How reliably do they detect the new variant? And: Does it make a difference whether you carry out the self-test as usual as a nasal swab or in the mouth and throat?
Experts continue to certify rapid tests as being highly reliable
As the virologist Christian Drosten reports in his well-known NDR podcast, experts continue to certify the high reliability of the rapid tests. These would generally also work with the new virus variant, since the rapid tests do not look for the spike protein, but for the N protein, which is still only present in a modified form in the omicron variant. Consequently, as virologist and virus evolution expert Björn Meyer explains, “the tests can detect it even if the N-protein looks a little different at omicron”.
The first studies are also available and still certify the correct results of the rapid tests. A study with 700 participants showed that one of the best-known rapid tests in the USA can still identify the new virus variant with certainty. The Paul Ehrlich Institute also checked the effectiveness of the rapid tests in its own investigations and, based on the current data situation, came to the conclusion that most rapid tests could detect an infection with omicron.
Experts continue to recommend rapid tests at Omikron
On Twitter, relevant experts such as Harvard epidemiologist Eric Feigl-Ding recommend taking the swab from the oropharynx. At the same time, he calls on physicians and authorities to adapt the test strategy that has been used up to now. He also relies on a study published by the University of Cape Town (Cape Town): This shows that Saliva samples are much better for diagnosing omicron infection than nasal swabs. The samples required for this were taken from the palate and above and below the tongue from the patients who were not subject to hospitalization. At the same time, the scientists point out that the study is only of limited significance in order to draw reliable conclusions for the omicron variant.
The President of the German Society for Immunology also recommends a new test procedure. She justifies this with the Differentness of the new variant: This would settle less in the lungs and more in the upper respiratory tract, which would result in milder courses overall. The virus could also tend to settle in the throat during the early phase of infection, while the alpha and delta variants have so far, as is suspected, been more detectable in the nasal cavity at the beginning of the infection. Consequently, a rapid test carried out in the throat could possibly detect the infection a day or two earlier.
Since Omikron: carry out a rapid test swab in the nose and throat
Since the purpose is to detect infections in good time, it should be considered to adapt the testing strategy. Ideally, suspected cases carry out the test in a “two-step procedure“ by: First in the pharynx and then in the nose. It is best to choose rapid tests that are approved for both the nose and the throat. The infectiologist Claudia Denkinger advises against using pure nose tests for the throat on your own.
Here’s how you do it:
- In front of a mirror, you should open your mouth as wide as possible and lower your tongue slightly so that the arch of your mouth is visible. The swab should now be gently rubbed along the back of the palate without coming into contact with the teeth.
- The stick can then be carefully inserted flat into both nostrils, parallel to the palate, and carefully rotated in a circle a few times. In this way, the inside of the nasal mucosa is better reached.
The ideal time to test is in the morning, if possible before brushing your teeth. In this way, any erroneous test results that could occur due to the consumption of food can be prevented.
It could be useful for vaccinated people to test themselves several times for omicron. As Christian Drosten emphasizes in the NDR podcast, this is mainly due to the fact that rapid tests on vaccinated people are generally less sensitive. The reason for this could be the lower viral load of the vaccinated, but also the faster immune system. Experts therefore recommend regular tests on at least two to three days a week.
However, it is not (yet) known which test recognizes Omikron best. Rapid test products are rather little regulated within Germany and have so far only been tested by the manufacturer himself. However, interested parties can refer to a list published by the Federal Institute for Drugs.
Response from social media
In a personal testimonial For example, a user by the name of “coffee in the head” published a comparison between two self-tests carried out during the discussion. While the self-test based on a nasal swab was negative, another rapid test, which took the sample from the oropharynx, revealed a positive result:
Read more on Techzle.com:
- Strengthening the immune system: How to arm yourself against viruses this winter
- Disposing of the Corona rapid test: In which garbage does the self-test belong?
- Corona antibody tests at dm: how useful are they?