Sexually transmitted infections and migration in Uganda: a population-based study.

Objectives: Migration is associated with increased risk of HIV infection in Africa, but evidence about non-HIV sexually transmitted infection (STI) burden among African migrants is limited.

Methods: We used data from the Sexually Transmitted Infection Prevalence Study, a cross-sectional population-based study of chlamydia, gonorrhoea, trichomoniasis, syphilis and herpes simplex virus type 2 prevalence in southern Uganda, to compare STI prevalence between adults aged 18 and 49 years with and without a recent history of migration. Migration status was determined using household census data, with a recent migration history defined as having moved into one's community of current residence within the last ~18 months. Unadjusted and adjusted modified Poisson regression models were used to compare individual STI prevalence risk by recent migration status with associations reported as adjusted prevalence risk ratios (adjPRRs) with 95% CIs. Adjusted models included participants' sex, age, community type, education, occupation and marital status.

Results: Among 1825 participants, 358 (19.6%) had a recent migration history. Overall, migrants exhibited a significantly higher combined prevalence of curable STIs (gonorrhoea, chlamydia, high-titre syphilis (rapid plasma regain ≥1:8) and trichomoniasis) as compared with long-term residents (34.4% vs 24.2%; adjPRR=1.23; 95% CI 1.03 to 1.47). Significant differences in curable STI prevalence by migration status were concentrated among persons living with HIV (49.4% prevalence in migrants vs 32.6% in long-term residents; adjPRR=1.42; 95% CI 1.10 to 1.85) and among women (38.8% in migrants vs 27.8% in long-term residents; adjPRR=1.26; 95% CI 1.01 to 1.58). High-titre syphilis prevalence was especially elevated among male migrants (11.2% in migrants vs 4.9% in long-term residents; adjPRR=1.82; 95% CI 1.06 to 3.13).

Conclusions: The prevalence of non-HIV STIs is higher among migrants. Tailored outreach and service delivery approaches that address the needs of mobile populations are crucial for integrated HIV and STI epidemic control in Uganda to optimise resources and reduce transmission risks.