Microbial Analysis of Contact Lenses

Introduction: Contact lenses are small, thin lenses which are worn directly on the surface of the eyes. They can be worn aesthetically or to correct vision. Contact lens related eye infections can lead to serious complications such as blindness, and are associated with several risk factors such as sleeping with lenses, exposure to water, not adhering to replacement schedules, and reusing disinfecting solutions, among others. The severity of the infection may vary with the degree of pathogenicity of the microorganism. Hygiene and handling of contact lenses play a very important role. The main aim of this study is to assess the microbial analysis of contact lenses.

Materials and Methods: A total of 15 lenses were collected in 2 ml sterile saline solution individually and manually agitated for five minutes. The lens was then removed using a sterile toothpick from the container. The sterile container was stored at 4°C till it was processed. 50 microliter of the sample was transferred using a pipette and inoculated on nutrient agar, blood agar and sabouraud dextrose agar. The microorganism (fungus or bacteria) were identified by standard protocol.

Results and Discussion: Bacillus, Staphylococcus aureus and CONS [Coagulase Negative Staphylococci] were found in blood agar. No fungal growth was found among the samples. More importance could be given to contact lenses handling and hygiene to avoid eye related bacterial and fungal infections.

Conclusion: In the present study, the total CFU (Colony Forming Unit) was found to be confluent in all the participants who wore contact lenses for 4 months compared to those who have worn contact lenses from 15 and 28 days. Only bacterial growth was seen in the culture plate. There was no fungal growth seen from the samples collected.