RT Journal Article SR Electronic T1 Double the reasons for giving the flu vaccine in 2020 JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP 647 OP 648 DO 10.3949/ccjm.87b.11020 VO 87 IS 11 A1 Brian F. Mandell YR 2020 UL http://www.ccjm.org/content/87/11/647.abstract AB