Fig. 1From: Seroprevalence and risk factors on Syphilis among blood donors in Chengdu, China,from 2005 to 2017The linearity of seroprevalence and serological incidence in blood donors from 2005 to 2017 (seroprevalence R2 = 0.9011, serological incidence R2 < 0.9)Back to article page