For two years, SARS-CoV-2 has been part of our daily lives. Some people are exposed regularly and have still not been contaminated. Luck, unnoticed infection or genetics? Futura provides some answers.
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[EN VIDÉO] Are we protected against Covid by having been infected? A coronavirus infection induces an acquired immune response. But for how long is it effective against variants?
The variant Omicron is spreading everywhere. Since the beginning of January, the number of new cases in France has fluctuated between 400,000 and 500,000 per day. Yet some of us have never had it. ” I am regularly contact case, I get tested each time. The test is always negative ” or ” My partner was positive and symptomatic, and I was not infected “. Are these people particularly respectful of barrier gestures? Not necessarily. Either way, the omicron variant is so contagious that it cannot be slowed down by conventional measures “, by the very admission of the Minister of Health Olivier Veran.
Didn’t know or didn’t know?
The disease at Covid-19 does not necessarily cause symptoms ! Today, tests are inexpensive and easily accessible: self-testsantigen tests in pharmacies without an appointment, PCR testing in the laboratory… This was not the case at the start of the epidemic when there was a serious lack of tests. It is very likely that a large number of people were infected without realizing it during the first months of the epidemic.
To know more, it is necessary to do a serology. A serological test involves looking in the blood for antibody directed against the virus. If they are present, it means that the organism has encountered the virus or else… that it has been vaccinated! It is not possible to distinguish the antibodies resulting from a natural infection from those resulting from the vaccination. The majority of French people who received at least one dose of vaccinehard to get to the bottom of it.
Genetic predispositions
While some patients will have a severe form of Covid-19 disease, others will get by with a simple cold, or even be asymptomatic. While some people will be symptomatic for a few days, others will have a long Covid and be unable to work for several months. Some patients will stay contagious much longer that others. Similarly, some will be contaminated simply by approaching a positive person, while others will still not be infected after several hours in an enclosed place with many positive people. the SARS-CoV-2 is still mysterious in many ways but one thing is certain: we are not all equal in the face of this virus! A recent study has identified a gene that would protect against severe forms of Covid. Conversely, another study has identified a gene that doubles the risk of dying from coronavirus.
To conclude, it is very likely that our heritage genetic is largely responsible for these disparities in contamination and forms of the disease.
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