Contact Lens Habits That Raise Infection Risk: A Swiss Survey Found Them in Every Type of Lens Wearer

Contact lenses are safe for most people when they are cared for properly. The most serious risk is infectious keratitis, an infection of the cornea that can scar the eye and, rarely, cost vision. Most of these infections are linked to how lenses are handled and worn. A survey study published in the Journal of Optometry looked at whether risky habits differ by lens type.

What the researchers did

At five eye care centers in Switzerland, researchers interviewed 156 contact lens wearers between August 2023 and August 2024 using a structured questionnaire. Participants were grouped by lens type: daily disposable soft lenses, reusable soft lenses, rigid corneal lenses, and rigid scleral lenses. The questions covered hand hygiene, wearing habits, and exposure to water or saliva.

What they found

• Wearers of rigid lenses felt better informed about lens care and showed fewer risky behaviors than soft lens wearers.
• Even so, risky habits appeared in every group.
• Those habits included handling lenses with possibly unclean hands, wearing lenses longer than recommended, sleeping in lenses, and exposing lenses to water or saliva.

The authors called for lens-specific education under professional supervision. Because this was a survey, it measured reported habits, not infections.

Safe-wear checklist

• Wash and dry your hands before touching lenses.
• Never rinse or store lenses in tap water, and never use saliva to wet them.
• Remove lenses before swimming, showering, or hot tubs, or wear goggles.
• Do not sleep in lenses unless your eye doctor has specifically approved it.
• Replace lenses and cases on schedule, and use fresh solution every time; do not “top off.”
• Daily disposables still need clean hands and should never be reused.

Warning signs

Remove your lenses and call an eye doctor the same day if you have eye pain, increasing redness, light sensitivity, discharge, or blurred vision. Bring your lenses and case with you. For more plain-language reading on everyday eye comfort, see epilasikmd.com.

Source: Risk behaviors for infectious Keratitis among contact lens wearers in Switzerland: an analysis by contact lens type (Journal of Optometry (PubMed), Oct–Dec 2026). This article is an educational summary written by Khanna Vision Institute and is not a substitute for medical advice.