嗅觉丧失或嗅觉缺失是COVID-19最早和最常见的症状之一。研究表明，它比其他众所周知的症状如发烧和咳嗽更好地预测这种疾病，但COVID-19患者嗅觉丧失的潜在机制尚不清楚。一项新的研究确定了最容易被这种新型冠状病毒感染的嗅觉细胞类型。令人惊讶的是，是嗅觉支持细胞，而不是神经元，易受新型冠状病毒感染。检测嗅觉并将嗅觉传递给大脑的感觉神经元并不属于易受攻击的细胞类型。

How COVID-19 causes smell loss

https://www.sciencedaily.com/releases/2020/07/200724141027.htm

David H. Brann, Tatsuya Tsukahara, Caleb Weinreb, Marcela Lipovsek, Koen Van den Berge, Boying Gong, Rebecca Chance, Iain C. Macaulay, Hsin-Jung Chou, Russell B. Fletcher, Diya Das, Kelly Street, Hector Roux de Bezieux, Yoon-Gi Choi, Davide Risso, Sandrine Dudoit, Elizabeth Purdom, Jonathan Mill, Ralph Abi Hachem, Hiroaki Matsunami, Darren W. Logan, Bradley J. Goldstein, Matthew S. Grubb, John Ngai, Sandeep Robert Datta. Non-neuronal expression of SARS-CoV-2 entry genes in the olfactory system suggests mechanisms underlying COVID-19-associated anosmia. Science Advances, July 24, 2020; DOI: 10.1126/sciadv.abc5801