RT Journal Article SR Electronic T1 Increase of early syphilis cases during the COVID-19 pandemic in the Czech Republic JF Sexually Transmitted Infections JO Sex Transm Infect FD BMJ Publishing Group Ltd SP 231 OP 231 DO 10.1136/sextrans-2021-055098 VO 98 IS 3 A1 Beatrice Bížová A1 Filip Rob A1 Jana Třešňák Hercogová YR 2022 UL http://sti.bmj.com/content/98/3/231.abstract AB