Disinfectants for Eye Cleaning May Be Ineffective

Scientists took a closer look on
disinfections; © PixelQuelle.de

Many people who have had eye exams are familiar with the applanation tonometer, a medical instrument pen that is used to check the pressure in your eyes. After the patient is given numbing eyedrops, an applanation tonometer is applied gently to the front surface of the eye and provides a pressure reading to check for glaucoma.

Health-care workers are required to disinfect the applanation tonometer after each use. However, a new study conducted by the University of North Carolina Health Care System has found that two of four disinfectants recommended for this purpose by the U.S. Centers for Disease Control and Prevention (CDC) are ineffective at inactivating adenovirus type 8, which is a common cause of epidemic keratoconjunctivitis (pink eye) outbreaks in eye clinics.

Fortunately, two disinfectants recommended by the CDC and the Association for Professionals in Infection Control and Epidemiology - 70 percent ethyl alcohol and 5,000 parts per million chlorine - were found to be effective in removing a test virus after 1 minute of contact.

"While adenovirus type 8 is relatively resistant to disinfectants, it is fortunate that these two disinfectants work well," said Dr. William A. Rutala, UNC Health Care's director of Hospital Epidemiology and a professor in the UNC School of Medicine. "The two disinfectants that did not inactivate adenovirus type 8 - three percent hydrogen peroxide and 70 percent isopropyl alcohol - should no longer be used for disinfecting applanation tonometers."

Based on their results, the researchers recommended that eye exam equipment be disinfected with 70 percent ethyl alcohol or 5,000 parts per million chlorine. In addition, health-care workers who handle the equipment should wash their hands with antimicrobial soap and water instead of alcohol-based hand rubs.

MEDICA.de; Source: University of North Carolina at Chapel Hill School of Medicine