The habit of spontaneously touching your face has been under fire recently, since it’s believed that this act can play a role in transmitting SARS-CoV-2. However, researchers in Australia contend that face touching may contribute to the body’s beneficial microbiome, including that of the ocular surface.
The hands harbor richer bacterial diversity than any other body part, according to investigators. And while spontaneous face touching has been linked with infectious conjunctivitis and the spread of herpes simplex virus and human papillomavirus, among other diseases, researchers hypothesize in Ocular Surface that face touching might be an essential step in developing and maintaining the diversity of the human microbiome.
“Diversity is integral in maintaining microbiota homeostasis, with self-touch potentially serving as a pathway to increasing diversity in the microbiome of the ocular surface, skin, gastrointestinal, and respiratory tracts, as supported by the high percentage of touches involving mucous membranes,” according to the publication.
If this is true, spontaneous face touching may significantly impact ocular health. Commensal and mutualistic microbiota — including those found on the ocular surface — protect us against foreign and opportunistic pathogens. However, the balance of the microbiome can be disrupted through loss of beneficial organisms, excessive growth of potentially harmful organisms, or loss of overall microbial diversity, according to researchers. Studies have found that dysbiosis can contribute to autoimmune uveitis, age-related macular degeneration, and open-angle glaucoma.
“It may be that whilst the eyes are at risk of infection through self-touch, they may paradoxically benefit through the acquisition of a mutualistic microbiome, protective not only for the eyes, but for the body as a whole,” the publication concludes.
Spencer SKR, Francis IC, Coroneo MT. Spontaneous face- and eye-touching: infection risk versus potential microbiome gain. The Ocular Surface. 2021;21(7):64-65. doi:10.1016/j.jtos.2021.04.008.