Perhaps the loss of the sense of taste and smell is the most common symptom associated with infection with Covid-19, as viral infection is one of the most common causes that lead to this annoying symptom, such as colds, sinuses or respiratory infections, but with regard to the Covid-19, the problem of losing smell sense is different .. Let’s learn more in the form of this health symptom coloration with Covid-19…
Many people infected with the Covid-19 experienced a sudden loss of sense of smell even though they did not have a blocked nose, so the loss of smell cannot be attributed to this.
Usually the loss of smell is caused by infection with a virus that attacks the respiratory system or sinuses. The researchers highlighted that some viruses are among the coronaviruses, which usually cause a cold and blockage in the sinuses, accompanied by some side effects on the patient’s health, such as headache, vomiting, and other symptoms.
Researchers examined the nose and sinuses of people who suffer from loss of smell due to corona, to find that the part of the nose that smells (the olfactory bulb) is covered by swelling of soft tissues and mucus, while the rest of the nose and sinuses appear normal and the patient does not have a problem breathing from his nose.
Researchers believe that the way the virus infects the body is by attaching (ACE2) receptors to the surface of the cells that line the upper respiratory tract, then a protein called (TMPRSS2) helps the virus to invade the cell, and once the virus enters, the virus can multiply, which leads to inflammatory response of the immune system, and this is what this virus attack in the body.
Researchers thought that the virus might infect and destroy olfactory neurons, and these are the cells that transmit the signal from the smell molecule in your nose to the area in the brain where these signals are interpreted as “odor.” But the study showed that the ACE2 proteins that the Corona virus needs to invade cells They are not found on olfactory neurons, but are found in cells called “ventral cells”, which support olfactory neurons.
Researchers expect that these support cells will be the ones that have been damaged by the virus and have swollen, but the olfactory neurons remain intact, and when the immune system defeat the virus, the swelling subsides, and the smell molecules have a clear path to their undamaged receptors and the sense of smell returns to normal.
Does the sense of smell and taste return to its normal functioning once the patient is cured from the disease?
Covid-19 is similar to Severe Acute Respiratory Syndrome “SARS”, as people infected with it suddenly lost their sense of smell and returned to them suddenly within a week or two. But sometimes this loss of smell stays for months or even years, especially in those who have experienced severe symptoms.
For people who encounter a quick recovery, it is possible that the virus only affected the cells lining their noses, on the other hand the people who recover more slowly, it is possible that the virus affected the nerve cells responsible for the sense of smell, and these cells may take longer to recover.