From Chlamydia to Gonococcus: Emerging Trends of Infectious Conjunctivitis and Keratoconjunctivitis in a Tertiary Ophthalmology Center in Switzerland from 2005–2025

Gonococcal and chlamydial conjunctivitis and keratoconjunctivitis are potentially sight-threatening ocular manifestations of sexually transmitted infections. Recent epidemiological data indicate rising rates of gonorrhoea and chlamydia infections worldwide, raising concerns about a possible increase in associated ocular infections. This retrospective single-center study analyzed the frequency and temporal trends of laboratory-confirmed gonococcal and chlamydial ocular infections in adults treated at the University Hospital Zurich between January 2005 and July 2025. Clinical characteristics, treatment, complications, and outcomes were additionally assessed for gonococcal cases. We identified 17 gonococcal and 121 chlamydial conjunctivitis or keratoconjunctivitis cases over the past approximately 20.5 years. A marked increase in gonococcal cases was observed between 2021 and 2025 (p < 0.0001), during which 70.6% of all cases were diagnosed. Complications occurred in 41.1% of gonococcal infections, including one corneal perforation requiring keratoplasty. Although gonococcal conjunctivitis and keratoconjunctivitis remain rare, their recent increase and risk of severe ocular complications highlight the importance of early recognition and prompt treatment. In contrast, chlamydial conjunctivitis was more common, affected a younger population, and showed a significant declining trend, with an average annual decrease of 5% (p = 0.0015).