Anosmia, the loss of sense of smell, and ageusia, an accompanying diminished sense of taste, have emerged as peculiar telltale signs of Covid-19, the disease caused by the coronavirus, and possible markers of infection. Doctor groups are recommending testing and isolation for people who lose their ability to smell and taste, even if they have no other symptoms of COVID-19 infection. The American Academy of Otolaryngology on Sunday posted information on its website saying that mounting a...