Effects of COVID-19 on Sense of Smell: Human Factors/Ergonomics Considerations

Objective We review the effects of COVID-19 on the human sense of smell (olfaction) and discuss implications for human-system interactions. We emphasize how critical smell is and how the widespread loss of smell due to COVID-19 will impact human-system interaction. Background COVID-19 reduces the sense of smell in people who contract the disease. Thus far, olfaction has received relatively little attention from human factors/ergonomics professionals. While smell is not a primary means of human-system communication, humans rely on smell in many important ways related to both quality of life and safety. Method We briefly review and synthesize the rapidly expanding literature through September 2020 on the topic of smell loss caused by COVID-19. We interpret findings in terms of their relevance to human factors/ergonomics researchers and practitioners. Results Since March 2020 dozens of articles have been published that report smell loss in COVID-19 patients. The prevalence and duration of COVID-19-related smell loss is still under investigation, but the available data suggest that it may leave many people with long-term deficits and distortions in sense of smell. Conclusion We suggest that the human factors/ergonomics community could become more aware of the importance of the sense of smell and focus on accommodating the increasing number of people with reduced olfactory performance. Application We present examples of how olfaction can augment human-system communication and how human factors/ergonomics professionals might accommodate people with olfactory dysfunction. While seemingly at odds, both of these goals can be achieved.