The reports from covid-19 patients are disconcerting. Only a few hours before, they were enjoying a cup of pungent coffee or the fragrance of flowers in a garden. Then, as if a switch had been flipped, those smells disappeared. Young and old alike are affected — more than 80% to 90% of those diagnosed with the virus, according to some estimates. While most people recover in a few months, 16% take half a year or longer to do so, research has found. According to new estimates, up to 1.6 million Americans have chronic smell problems due to covid. Seniors are especially vulnerable, experts suggest. “We know that many older adults have a compromised sense of smell to begin with. Add to that the insult of covid, and it made these problems worse,” said Dr. Jayant Pinto, a professor of surgery and specialist in sinus and nasal diseases at the University …