Can a loss of smell be an early warning for a COVID-19 infection? Multiple reports have surfaced, primarily from Europe and the United States, from physicians and ear, nose and throat specialists, of COVID-19 patients complaining of an inability to smell — or anosmia. However, it is not clear whether neurons in the brain that are responsible for recognising various odours are damaged, or whether other cells may be involved.
Also read | ‘Heat is not a deterrent for transmission’: Your COVID-19 queries answered
Not directly
Researchers at Delhi’s Indrapastha Institute of Information Technology report in the study that is still being peer-reviewed but available as a public preprint, that it is not neurons but a class of cells in the upper regions of the nasal cavity that may be involved: these are called sustentacular cells and horizontal basal cells. Crucially, both are not directly involved in helping us smell, but nourish and support the cells that help us do, and so the virus may be inflicting an indirect attack on the olfac