What do sinks & contact lenses have in common?

Every infectious diseases doctor hates Fusarium, as therapeutic options are limited and relatively ineffective. I suspect the ophthalmologists do too, since Fusarium can cause severe keratitis in contact lens wearers.

This month's issue of Journal of Clinical Microbiology has an interesting study, funded in part by Bausch and Lomb (the maker of a particular contact lens cleaning solution that appeared to be associated with cases of Fusarium keratitis), on detecting the environmental source of the organism. Like many of the pathogens that infect profoundly immunosuppressed patients, Fusarium is also found in the environment, but unlike many other opportunistic fungal pathogens, it doesn't enter the body via the respiratory tract.

Investigators in this study sampled nearly 500 drains, primarily of bathroom sinks in 7 eastern states as far north as Pennsylvania, as far south as Florida, as well as California. They found that 66% of sink drains harbored Fusarium. Moreover, the most common strains detected are the most common strains that cause clinical infections. Importantly, this organism produces and lives in biofilm, which not only coats your sink drain, but can coat your contact lenses when they are inappropriately cleaned.

Photo: Fusarium macroconidia