Ying-Hen Hsieh
China Medical University, Taiwan
Title: Modeling Syphilis in older population in Taiwan: Testing adequate but education lacking
Biography
Biography: Ying-Hen Hsieh
Abstract
Background/Objective Sexually transmitted disease is an ancient disease, although efficient treatment is available. Taiwan disease surveillance system disclosed that syphilis is the most common sexually transmitted disease. Among different age groups, the older population over 50 years of age had a relatively higher incidence. The study aims to focus the current syphilis epidemic in the ≧50 population in Taiwan.
Material and Methods Government syphilis surveillance data is used to infer the number of age over 50 years infected persons. Moreover, we utilize a discrete-time compartmental model to estimate important epidemiological parameters (i.e., infection rate, reporting rate) for two time periods, namely 2003-2006 and 2012-2014, in order to ascertain the recent trends of the epidemic.
Results Estimates for the first period (2003.9-2006.8) reveal that, new numbers entering ≧50-year old age group that are at risk of infection are 39.41% of 49-year-old population annually. The syphilis incidence of 50-plus age group is 1.6 cases per 100,000 persons. Estimate from the second period (2009.1-2011.12) indicate that, new numbers entering ≧50-year old age group that are at risk of infection are 1.26% of 49-year-old population annually. The syphilis incidence among 50-plus is 12.6 cases per 100,000 persons. Comparing the two period estimates, syphilis incidence surged sharply from 1.6 to 12.6 cases per 100, 000 persons, even though we have a decrease in newly entering syphilis at risk population (39.41 % to 1.26%). However, there has been a 3-fold increase in infection rate among the at-risk population.
Conclusions Syphilis incidence among age 50 and over population is increasing. Significant progress has been made on syphilis testing/surveillance program which led to substantial reduction in susceptible cases in general population. However, sexually transmitted disease prevention education program still need to be improved, to reduce infection in all adults, including the older aged population.