 Undocumented migrant sex workers, SW, face a high prevalence of sexually transmitted infections, STIs, and a high rate of loss to follow-up, LTFU. Transgender females, TF, are particularly vulnerable to these risks. The study found that having symptoms or a history of STIs increases the likelihood of contracting another STI, while engaging in at-risk sexual behavior decreases Additionally, older patients have a higher likelihood of LTFU. These findings suggest that targeted interventions are needed to reduce the burden of STIs among this population. This article was authored by Alessandro Donassi, Agnes Copani, Beatrice Zolli, and others.