RT Journal Article SR Electronic T1 STIs during the first and second wave of COVID-19 in Denmark JF Sexually Transmitted Infections JO Sex Transm Infect FD BMJ Publishing Group Ltd SP 150 OP 151 DO 10.1136/sextrans-2021-055021 VO 98 IS 2 A1 Heerfordt, Ida M YR 2022 UL http://sti.bmj.com/content/98/2/150.abstract AB