When West Nile virus turns deadly

James Parravani came down with flu-like symptoms the day before his daughter’s wedding reception. He had a fever, a headache, and chills. It was Labor Day weekend 2021, and his family thought he might have COVID-19. But a test at an emergency room near his home in Westchester, New York, came back negative. 

The ER doctors quickly transferred Parravani to Yale New Haven Hospital in Connecticut, where he had received a kidney transplant a year prior. The specialists there suspected he...