TORONTO -- While loss of smell and/or taste has affected approximately 80 per cent of COVID-19 patients, most recover within a few weeks. For a small number of people, however, these senses have yet to return. According to a study published in the Journal of Internal Medicine in January, nearly five per cent of the 2,500 COVID-19 patients researchers examined had not recovered their olfactory function six months after their initial infection. The average recovery time for the majority of patients in the study, however, was 18 to 21 days after their initial infection. Itâs still unclear why some patientsâ senses of smell and taste donât return months after their infection.