The main neurological manifestation of COVID-19 is loss of smell or taste. The high incidence of smell loss without significant rhinorrhea or nasal congestion suggests that SARS-CoV-2 targets the chemical senses through mechanisms distinct from those used by endemic coronaviruses or other common cold-causing agents. Here we review recently developed hypotheses about how SARS-CoV-2 might alter the cells and circuits involved in chemosensory processing and thereby change perception. Given our limited understanding of SARS-CoV-2 pathogenesis, we propose future experiments to elucidate disease mechanisms and highlight the relevance of this ongoing work to understanding how the virus might alter brain function more broadly.

COVID-19 的主要神经系统表现是嗅觉或味觉丧失。嗅觉丧失的发生率很高，但没有明显的鼻漏或鼻塞，这表明 SARS-CoV-2 通过与地方性冠状病毒或其他常见感冒病原体不同的机制来靶向化学感官。在这里，我们回顾了最近提出的关于 SARS-CoV-2 如何改变参与化学感应处理的细胞和回路，从而改变感知的假设。鉴于我们对 SARS-CoV-2 发病机制的了解有限，我们建议未来进行实验来阐明疾病机制，并强调这项正在进行的工作与了解该病毒如何更广泛地改变大脑功能的相关性。