Did you know why the reduction in ability to taste (hypogeusia) and the loss of the olfactory sense (anosmia) are viewed as alarm signals for COVID-19?

In a region in France patients diagnosed with COVID-19 were asked to fill out a questionnaire with reported symptoms. 32% of them confirmed that hypogeusia and anosmia were new symptoms.  In the paper the authors assert that these symptoms are caused because SAR-CoV2 has the ability to invade the olfactory nerves.