Association between syphilis seroprevalence and age among blood donors in Southern China: an observational study from 2014 to 2017

Wu, Xiaobing; Guan, Yang; Ye, Jianbin; Fu, Hanlin; Zhang, Chunlai; Lan, Lina; Wu, Fengxin; Tang, Fen; Wang, Feng; Cai, Yumao; Yu, Weiye; Feng, Tiejian

Shenzhen, a special economic zone located in southern China and with a population of >10 million, is one of the cities that most affected by syphilis. The reported incidence of syphilis was over 60 per 100 000 in last 10 years, which was much higher than the national incidence. 5, 10 Consistent with the aforementioned characteristics of varied age groups, a rapid increase in syphilis incidence among older adults was observed in Shenzhen. 11 Studies usually considered blood donors as a representative of the general population and used the prevalence data of blood donors for real-time surveillance and identification of high-risk groups. 12 Whether the syphilis seroprevalence among blood donors agrees with reported incidence characteristics remains to be studied. Shenzhen launched a comprehensive program, the Shenzhen Program for Syphilis Prevention and Control (SPSPC), in November 2013 to enhance syphilis screening among blood donors and five other subgroups (HIV voluntary counsellors, methadone maintenance treatment users, female sex workers, men who have sex with men, and women of childbearing age), as well as case management, including diagnosis, treatment, and follow-up, for syphilis-infected adults. 13 Based on the data from the SPSPC, this study aimed to examine differences in syphilis seroprevalence among blood donors and describe the distribution of serological titres among syphilis-infected donors with respect to age groups, to confirm the syphilis epidemic characteristics in southern China and support the design of effective interventions for older adults. Before donation, all potential donors needed to sign a donation registration form, complete a health history questionnaire, and undergo rapid testing and a brief physical examination. A concise introduction of blood use, donation procedure, laboratory testing, and legal and regulatory requirements was shown at the front of 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59