An observational study of 219 unvaccinated long-COVID patients with neurologic symptoms in the Amazon concludes that 64% had a persistently impaired sense of smell, which the authors said could be permanent.

Brazilian researchers evaluated 219 adult long-COVID patients at a rehabilitation center at a public university in the Amazon from Sep 9, 2020, to Oct 20, 2021. A total of 74.9% of the patients were women, 88.6% were 18 to 59 years old, 94.1% had more than 9 years of education, and 52.5% had a monthly income of up to US $192.

Most had likely been infected with wild-type SARS-CoV-2 because symptom onset occurred in spring 2020. Participants underwent neurologic examination and completed a questionnaire about their daily activities.