(P411) Syphilis prevalence and correlates in rural, southwestern Uganda

Background:

The global incidence of syphilis increased from 8.8 to 14.1 million from 1990 to 2019. Understanding the current syphilis burden and epidemiology will allow health providers and policymakers to design effective screening and treatment programs. However, such data are lacking in many communities. We describe a population-based syphilis screening program in a rural community in southwestern Uganda with the aim of describing prevalence and correlates of syphilis in an area without such data.



Methods:

In June 2019 we conducted a cross-sectional, population-based study of adults over 18 years of age. Two-stage syphilis testing was completed with initial treponemal pallidum hemagglutinin (TPHA) rapid immunochromatographic testing, confirmed by rapid plasma reagin (RPR) in those who tested positive by TPHA. All participants with a positive TPHA result were offered benzathine penicillin 2.4 million units on the day of screening, followed by second and third weekly doses at a local healthcare facility, per local guidelines. Multivariable logistic regression was used to estimate correlates of TPHA positivity. Variables with a univariable p-value ≤ 0.20 were included in a final multivariable logistic regression model.

Results:

Among 749 participants who participated in this population-based study, 724 (96.7%) completed syphilis screening. The median age was 41 years (interquartile [IQR] range, 30-52), 470/746 (63%) were women, and 86/724 (11.9%) tested positive for HIV. Overall, 85/724 (11.7%) had a positive TPHA test result and 27/77 (35%) reported having a prior sexually transmitted infection (STI). Among the 66/85 (78%) with RPR testing, 22/66 (33%) had non-reactive, 36/66 (55%) had 1:1, 9/66 (14%) had 1:2, and 1/66 (2%) had 1:4 titers. TPHA positivity was associated with older age, higher education, poor socioeconomic status, living with HIV, reporting a prior STI, and condom use at last sex (Table 1).



Discussion:

We describe a high prevalence of current or former syphilis (11.7%) in a population-based study in rural Uganda. Additionally, most participants had low but reactive RPR titers, likely due to a combination of early, latent, and previously treated syphilis infection. Syphilis screening and surveillance programs in this region require expansion beyond antenatal and HIV clinics to capture populations not routinely in care.