Trend of Syphilis Infection among Voluntary Blood Donors in Foshan City from 2008 to 2017

Abstract

To investigate the prevalence of syphilis infection in voluntary blood donors in Foshan City, so as to provide reference for improving the infusion blood safety strategy of city. A total of 657 382 voluntary blood donors in Foshan City from January 2008 to December 2017 were selected. The blood samples were tested for treponema pallidum. The prevalence trends, the detection rate of treponema pallidum infection and epidemiological data were statistically analyzed. Enzyme-linked immunosorbent assay (ELISA) was performed for antibody screening in blood samples. The two-hole retest was then performed for the samples which were positive in initial test, meanwhile, they were also confirmed by the treponema hemagglutination blood coagulation test (TPHA). First, the annual infection rate of treponema pallidum in Foshan City from January 2008 to December 2017 was 0.43%, 0.40%, 0.41%, 0.43%, 0.50%, 0.32%, 0.36%, 0.32%, 0.37% and 0.32%, respectively. A total of 2502 cases of treponema pallidum infection were detected, the overall infection rate was 0.38%, and the infection rate decreased year by year (x2=23.826, P＜0.05). Second, among the 657 382 samples of voluntary blood donors, 2 502 were showed the positive treponema pallidum antibody (0.38%). In 2015-2017, 791 donors were showed positive treponema pallidum antibody, 676 case out of which were confirmed positive, 0.34% with the positive coincidence rate of 85.46%. Third, this group of 676 syphilis infection cases were male-dominated (0.35%, 577/164 484). The age distribution was 18-53 years old, and the average age was 32 years, among which 35-44 years old accounted for 0.33% (138/41 858). The education level of in donors with treponema pallidom positive mainly ranked at low or lower levels under janior college (0.32%, 571/180 917). The occupation is mainly outside work and company staff (0.39%, 452/115 101). The marital status is mainly unmarried (0.29%, 377/130 905). The place of origin is mainly non-local (0.29%,570/198 063). The positive rate of treponema pallidum shows a downward trend in 2008-2017. Among the individuals with comfirmed TP antibody positive in 2015-2017, the non-local, unmarried and low educated males are main population, moreover more than half of them are migrant worker or company employeers.