<prompt> A 17-year-old girl with keratitis and severe pain in the eye came to the hospital and acanthamoeba keratitis was suspected. The patient gave the history of the following 4 points. Out of these which is not a risk factor for acanthamoeba keratitisExtended wear contact lensExposure to dirty waterCorneal traumaSquamous blepharitis  <response>: Corneal infection with acanthamoeba result from direct corneal contact with any material or water contaminated with the organism. The risk factors are : i Contact lens use, ii Trauma, iii Opportunistic infections. 