Abstract
In 2006, we reported the effectiveness of the anti-reflux valve in ultrasonic nebulizers used for aerosol treatment of the nasal cavity and paranasal sinuses. In this study, we cultured bacteria sampled from the drug solution cups of ultrasonic nebulizers before and after daily practice at otorhinolaryngology clinics, and evaluated whether the drug solution reservoirs were contaminated after use by many patients. In the first period of the experiment, bacteria were detected in samples from some drug solution reservoirs after daily practice, but none were detected in the samples collected before the start of daily practice. After the first period of the experiment, the nebulizers were left in the sink for about 1 week without use. In the second experimental period, non-fermenting gram-negative rods were detected before daily practice from the nebulizers placed in a wet environment for a long period, indicating the necessity of improving the disinfection method for these devices.
Specifically, the mechanical removal of microbial biofilms using a sponge or brush and sufficient drying were considered necessary.
In the third period of the experiment, performed after measures taken to improve the disinfection method, no bacteria were detected in the samples collected after daily practice.
