AdvertisementWhat's ailing long COVID patients? A new federal study looks for clues03:54Download AudioResumeMay 24, 2022Rob SteinfacebookEmailNancy Rose, right, who contracted COVID-19 in 2021 and continues to exhibit long-haul symptoms including brain fog and fatigue, cooks for her mother, Amy Russell, left, at their home, Tuesday, Jan. 25, 2022, in Port Jefferson, N.Y. Researchers are trying to understand what causes these long COVID symptoms. (AP)