Millions of people, including tens of thousands of Israelis who recovered from COVID-19, are likely suffering from “distortion of odors” or “hallucinating odors,” even if they recovered from the virus months ago, according to new research published by the Hebrew University of Jerusalem.

The study, conducted through an international association for the study of the senses of taste and smell called the Global Consortium for Chemosensory Research, found that during the course of the disease, incidents of parosmia – a condition in which certain odors smell different and often unpleasant – and phantosmia – a phenomenon of hallucinating odors that do not exist in reality – occurred in only about 10% of patients who lost their sense of smell. However, after recovery, the incidents increased significantly: 47% reported parosmia and 25% phantosmia.

The typical reports received for patients with parosmia are things such as, “There are things that now smell different and unpleasant” or “like chemicals.” Reports of phantosmia included reactions such as “Sometimes I smell a fire, which no one around me smells.”