As the pandemic continues to unfold, so too do the long-term side effects of COVID-19. Long COVID is the term used to describe the symptoms that follow an active infection, which some people have found to last for several months after catching the virus. Symptoms associated with the condition have so far included loss of taste and smell, fatigue, "brain fog" and shortness of breath. Now, a new symptom has been added to the long COVID roster: parosmia.
Parosmia is a dysfunction of smell and has so far been reported most by younger COVID-19 patients, as well as healthcare workers. The condition differs from a loss of smell, as instead, sufferers find they can smell something that doesn’t correlate to their environment. Among the parosmia presentations, individuals have reported smelling “disgusting” odors including burning, sulfur, and fish.
In an interview with CNN, ear, nose, and throat (ENT) surgeon Professor Nirmal Kumar described the parosmia symptoms as "very strange and very unique". Kumar, who is the president of ENT UK (a professional membership body representing Ear, Nose, and Throat surgery) was the first medical worker to identify loss of smell as a symptom of COVID-19. The condition that causes us to be incapable of smelling anything is called anosmia.
While examining patients experiencing anosmia, Kumar noticed that among them were people who were actually experiencing parosmia, where smells are distorted. Unfortunately, it seems the smells are almost always distorted for the worse, and the condition can have an enormous impact on quality of life and mental wellbeing.
"This virus has an affinity for the nerves in the head and in particular, the nerve that controls the sense of smell,” said Kumar. "But it probably affects other nerves too and it affects, we think, neurotransmitters - the mechanisms that send messages to the brain… Some people are reporting hallucinations, sleep disturbances, alterations in hearing. We don't know exact mechanisms, but we are finding ways to try and help patients recover."
Some recovering COVID-19 patients are turning to “smell therapy” to try and restore their sense of smell, which Kumar says has some promising early reports as to its efficacy. The UK charity AbScent is centered around such therapies, which it says can help both parosmia and anosmia patients to restore their sense of smell. In collaboration with ENT UK and the British Rhinological Society, they are collating data from thousands of patients with a goal to better understanding the emerging symptoms of long COVID and how best to treat them.