**3. Epidemiology**

The annual incidence of CLAIK per 10 000 wearers ranges from 0.4–4.0 for rigid gas permeable (RGP) contact lenses, 2.2–4.5 for daily use of soft contact lenses, and 9.3–20.9 for overnight soft contact lenses wear [11]. Hence, daily wear of RGP contact lenses continues to have the lowest infectious keratitis rates [12]; however, the incidence of associated microbial keratitis remains unchanged despite the development of new contact lens materials [13].

Orthokeratology (ortho-K) for myopia prevention and cosmetic and decorative lenses have recently gained popularity among young wearers. On the one hand, ortho-K patients are closely monitored during treatment by their practitioners; conversely, cosmetic contact lens wear (color or party) lacks care education and professional supervision. There are reports of microbial keratitis in both wear modalities [14, 15]. In the case of cosmetic lens wear not dispensed by eye care professionals, a report shows an increased risk of infectious keratitis by a factor of 12.3 (OR 95%- CI = 4.8–31.5 Furthermore, lack of lens care education in the same study increased the risk of infectious keratitis by 26.5 times (OR 95%-CI = 10.0–70.2) [16].
