A study carried out jointly by French and Belgian doctors brings a little optimism to the wealth of information circulating on the Covid-19 pandemic.
Since the start of the health crisis caused by the Sars-CoV-2 virus, we know a little more about the multiple symptoms of Covid-19 every day. There is cough, fever, fatigue.
Other symptoms are milder, but surprising. Studies are being done by doctors to understand where these symptoms come from and what they mean.
Loss of taste (ageusia) and loss of smell (anosmia) are also known to be hallmarks of the disease. Regarding the loss of smell, it is actually unpleasant, but rather a good sign!
Researchers from the Suresnes and Mons hospitals conducted a study on 1,300 patients with Covid-19. This follows a first study published in April 2020 on the symptoms of the coronavirus. They classified them into four groups, according to the level of severity of the infection in the body, classified according to the WHO. The mild ones can stay at home in quarantine, the moderate ones have difficulty breathing, the severe and very severe ones needing oxygen in the hospital, intensive care or even resuscitation.
The researchers' observation is strong: "The results show that among the patients who were in groups 3 and 4, that is to say the most severely affected, only 10 to 15% of them had a loss of smell. On the other hand, they were 70 to 85% with this symptom in groups 1 and 2, ie the mildest cases ".
Mild symptoms, which are treated fairly well
Ultimately, ageusia and anosmia classify you as the mildest cases of Covid-19 infection.
More good news: the majority of patients regain their sense of smell two months after the end of the disease. It is possible to re-educate it, just like the taste. But why is the body thus losing its senses? This is a sign of the body's immune response, which fights against the virus and contains it.
"Our hypothesis is that the loss of smell means that the virus arrives not only in the nose, but also in the central nervous system. MRI images then show damage to the olfactory bulb, a region located at the base of the brain and which has a major role in smell. The virus is then contained by the immune system. This prevents it from having too much passage through the lungs and into the blood, which is the case in the most serious cases ", explains Doctor Jérôme Lechien to our colleagues at Le Parisien.
This European study was conducted by Dr Jérôme Lechien, Head of the Ear, Nose and Throat Department of the Foch Hospital in Suresnes (Hauts-de-Seine) and Professor Sven Saussez from the University of Mons (Belgium).
If you are concerned by a suspicion of contamination with Covid-19, the government has published a small video to help you react well.