Characterization of transient and resident conjunctival microbiota in young adults

Abstract

Ocular microbiota is mainly found in the conjunctiva and consists of bacteria of the genera <em>Staphylococcus corynebacterium</em> spp., <em>Bacillus</em> spp., <em>Neisseria</em> spp., <em>Moraxella</em> spp., and <em>Streptococcus</em> spp. This diversity may vary according to seasonal conditions, temperature, age, and environmental exposure. <em><strong>Objective</strong><em> To characterize the diversity of resident and transient conjunctival microbiota in young adults. <em><strong>Methodology:</strong><em> A cross-sectional observational descriptive study including 67 young adults, men and women between 18 and 25 years of age, who met the inclusion criteria and agreed to sign the informed consent form. Two samples from the conjunctival sac were collected from each subject, with an interval of one week. These were cultured on blood agar and chocolate agar at 37 °C for 24 hours. Isolated colonies were identified using the VITEK automated system. <em><strong>Results:</strong><em> Sixteen genera and 29 different species were identified. The most common genus was <em>Staphylococcus</em> (55.6%), followed by <em>Acinetobacter</em> (12.0%), <em>Bacillus</em> (7.0%), <em>Pasterella</em> (4.6%) and <em>Escherichia</em> (3.7%). Resident microbiota consisted primarily of the genus <em>Staphylococcus</em> and its most representative species were <em>S. epidermidis</em> (50.0%) and <em>S. lentus</em> (13.3%). <em><strong>Conclusion:</strong><em> There is a great diversity of bacteria in the conjunctival flora, greater in the transient than in the resident microbiota this probably depends on the environment in which the individual lives.