According to data from the World Health Organization (WHO), since the beginning of the pandemic, more than 73 million cases of Covid-19 have been reported worldwide and more than 1.6 million deaths. Although many people have respiratory symptoms, an important part of positive diagnoses are asymptomatic or presymptomatic with a longer incubation period, which leads to a high number of carriers. This, added to the high transmissibility of the virus, contributes to its rapid spread.
Among the varied symptoms is also the loss of smell or taste, a condition that is common to other infections, such as the common cold or the flu. According to studies carried out in different countries, this problem affects between 5 and 85% of people infected with the coronavirus.
Now researchers from the Hospital Clínic-IDIBAPS have analyzed the prevalence of this symptom in various subgroups of patients and concluded that more than half of the infected people had a severe loss of smell (53.7%) or taste (52.2%) and, of these, in more than 90% of the deterioration affected both directions.
Posted in Journal of Investigational Allergology and Clinical Immunology, one of the studies evaluates data from 846 patients and 143 controls from 15 Spanish hospitals and indicates that dysfunction of smell or taste (DOG) was twice as common in patients with Covid-19 compared to controls.
On the other hand, the results showed that DOG is a common symptom in Covid-19 mainly in young patients and not hospitalized. Among patients with DOG, one in three had loss of taste or smell as the initial symptom of the disease.
Study smell, useful for detecting patients
In another study, published in the European Archives of ORL, the frequency and severity of DOG was evaluated in non-admitted patients positive for PCR for SARS-CoV-2, compared to controls with the common cold or flu and negative PCR. 197 patients and 107 controls from five Spanish hospitals were included.
The frequency of loss of smell (70.1%) and taste (65%) was significantly higher among Covid-19 patients compared to controls (20.6% and 19.6%, respectively). The simultaneous loss of taste and smell was also greater in the infected patients (61,9 % vs 10,3 %).
“In the two investigations, the loss of smell and taste due to Covid-19 was predominant in young people under 50 years of age and in women, who represented 63% of those affected with this symptomatology,” the authors point out. «In the absence of loss of smell due to other respiratory diseasessuch as severe allergic rhinitis, acute or chronic rhinosinusitis, should alert physicians to the possibility of having a SARS-CoV-2 infection. ‘
Experts argue that the study of the sense of smell may be useful to identify patients who require measures of isolation or initial treatment and could reduce the number of infections
In this sense, the experts argue that the study of the sense of smell can be useful to identify patients who require isolation measures or initial treatment and could reduce the number of infections by preventing the spread of the coronavirus.
Train the sense of smell to recover it
Three out of four patients with Covid-19 present an improvement in the loss of smell after one month from diagnosis. This improvement over time indicates that the virus causes inflammation, and not a permanent damage to the olfactory neuroepithelium, in most patients.
If loss of smell persists, initiation of treatment should be considered, although the efficacy of currently available therapies for postviral olfactory dysfunction is unknown. “There are no effective drugs in the loss of smell and taste due to viruses,” the authors explain. “However the olfactory entrenamiento it can help the recovery of smell ».