Scientists at the KI Research Institute found that most of the long-term symptoms disappeared within a year after a mild Covid-19 infection. The results are published in: BMJ.
Prolonged coronavirus is defined as persistent symptoms or the onset of new symptoms four weeks after infection. In the new study, the researchers used electronic records from a healthcare facility in Israel. It included data from nearly 2 million people tested for COVID-19 between March 1, 2020, and October 1, 2021.
The researchers looked at only mild cases of infection and also took into account other factors such as alcohol use, smoking, socioeconomic characteristics, and the presence of chronic diseases.
After infection, patients frequently experienced loss of smell and taste, concentration and memory impairment, shortness of breath, weakness, palpitations, streptococcal tonsillitis, and dizziness, as well as hair loss, chest pain, cough, muscle pain, and respiratory problems. Results were similar for males and females and for alpha and delta variants.
Vaccinated people who contracted the coronavirus were less likely to suffer from respiratory problems compared to unvaccinated infected patients. The risks of other symptoms of prolonged coronavirus were similar in the vaccinated and unvaccinated groups.
These data show that the vast majority of patients with a long course of coronavirus after a mild infection do not suffer from serious or chronic long-term illness.