Background Inmates suffer from mental and physical ailments combined with substance misuse and addiction which are often underreported or disregarded by sufferers, for fear of being stigmatized. This vulnerable group has complex medical and psychosocial needs and hence gathering data is essential for a holistic approach to care.Objectives Understanding the interplay between sexually transmitted (STIs) and blood borne infections, substance misuse and mental health is essential to enable targeted interventions and outreach programmes. The aim was to analyse the occurrence of STIs, hepatitis and tuberculosis in inmates at the main custodial facility in Malta; to assess risk behaviours and vulnerabilities through an outreach programme; to offer treatment and referral and to develop recommendations for screening of prison inmates.Methods A mixed methodology study was used which involved analysis of health data pooled from the Genitourinary Clinic (GUC) and Corradino Correctional Facility (CCF) in Malta. ResultsIn the study period, 206 inmates were tested for STIs, 67.9% males, aged between 14 and 72. Only 27% were not sexually active in the 6 months prior to testing. Among those sexually active, 31% had had sex with casual partners and 43% had never used condoms for sexual intercourse. Seventy-five percent admitted to drug use. The most common STI diagnosed was HPV (16.5%), followed by syphilis (5.8%). Genital dermatoses were also frequent (9.2%). The prevalence of Hepatitis C was high (24.5%), in relation to intravenous drug use. ConclusionThe authors advocate for more collaboration between sexual health clinics and prisons to address educational interventions and STIs' testing. Cultural and linguistic barriers should be considered when devising national health strategies and screening recommendations in custodial settings. Adequate follow-up should extend into the community setting once inmates leave the prison to ensure a continuum of care.