Your cell phone can be detrimental to your ocular health—and not just because of the blue light exposure and excessive near vision tasks. A new study shows that the phones of contact lens–wearing university students are highly contaminated with pathogenic bacteria and may act as carriers, eventually infecting eyes.

The Jordan-based investigators swabbed 63 patients’ conjunctivas, mobile phones and contact lens storage cases—a total of 189 swabs.

Altogether, the team found nine bacterial species: Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis, Shigella dysentery, Pseudomonas aeruginosa, Proteus mirabilis, Citrobacter spp., Klebsiella pneumoniae and Escherichia coli.

Nine of the mobile phones (26%) and seven (21%) conjunctival samples were contaminated with five different bacterial species. While the researchers suspect the phones act as a carrier of the bacteria, the highest level of contamination was detected in the contact lens storage cases. Eighteen (52%) bacterial isolates were detected in cases.

Waleeda AM, Lua’ib A, Wisamb S, Sanad J. Antimicrobial susceptibility of bacterial isolates from the conjunctiva, storage cases and mobile phones of university students using contact lenses. Contact Lens & Anterior Eye. November 10, 2019. [Epub ahead of print].