 This DWCIE Study is a prospective cohort study of patients fit to the FDA approved and marketed lotrafilcon A Ciba Vision, Air Optix Night Day Aqua soft contact lenses for daily wear DW with monthly disposal. 218 healthy myopic nearsighted or hyperopic farsighted patients with minimal or no astigmatism and no contraindications to DW lens use will be followed for 1 year. The primary outcome is the risk of development of a corneal inflammatory event CIE as defined by slit lamp findings and patient symptoms. The main exposure of interest is microbial contamination of study lenses. 