Repeated Negative Serological Testing in Otherwise Healthy Patients With Coronavirus Disease 2019. (29th July 2020) - Chatzidimitriou, Maria; Chatzopoulou, Fani; Gavriilaki, Eleni; Chatzivasileiou, Panagiota; Rousis, Dimitris; Meletis, Georgios; Chatzidimitriou, Dimitrios