Some people infected with the coronavirus suffer from the infection asymptomatically or mildly enough that the symptoms are not bothersome. Meanwhile, over time, these people develop complications that are characteristic of COVID-19. As explained by prof. Włodzimierz Gut, virologist, it is easy to check if someone has had COVID-19, even if the person is vaccinated.
As reported by the Institute of Human Genetics of the Polish Academy of Sciences, the Omikron variant is more contagious than previous SARS-CoV-2 variants. However, the most common symptoms of infection are mild, and many people become asymptomatic.
The Polish Press Agency asked the virologist prof. Włodzimierz Gut. "Of course, it can be easily checked by applying any of the tests available on the market" - said the expert. He explained that the tests "look" for one of the nucleoproteins, i.e. proteins that make up the mRNA envelope of the virus. "These proteins are in the virus, but the vaccine does not contain them, so even people vaccinated three times can find out if they had + close contact + with the pathogen" - explained Prof. Gut. However, he added that it is impossible to check when the infection occurred.
Currently, there are three types of such tests available for sale: qualitative, semi-quantitative and quantitative.
Qualitative tests only inform about the possibility of contact with the coronavirus, while quantitative tests also examine the amount of antibodies, and thus some types of such tests allow - as PAP writes - to determine whether a person has antibodies obtained as a result of vaccination or passed the infection asymptomatically and therefore also obtained immunity.
This type of test detects the presence of two proteins - the nucleocapsid phosphoprotein (N) and the S1 subunit of the spike protein (S).
A person with a history of COVID-19may develop antibodies against both the S protein and the N protein.
On the other hand,the person who has only been vaccinated,will only develop antibodies to the S protein.