About Cat Tapeworms & Human Blindness

Humans get tapeworms much more frequently from food than than from their pets, but transfer from felines is possible and, in rare cases, can lead to blindness.

  1. Animal Infection

    • Tapeworms infect cats through an intermediary host, most often a flea. The cat, irritated by the flea on its skin, licks or bites it and ingests the flea, along with the tapeworm it carries.

    Transmission to Humans

    • Transmission must occur though the mouth. Kissing pets and poor hygiene are the primary causes. Most cases of human infection involve children,

    Blindness

    • Blindness is caused by cysts that act like slow-growing tumors, increasing pressure on the eye. These cysts can grow up to 14 inches in diameter.

    Treatment

    • Treatment usually requires surgery and often is followed by a course of drugs to kill any residual tapeworms in the system.

    Why Blindness is Rare

    • The species of tapeworm that causes cysts--echinococcus granulosus--is more rare than other forms of tapeworms and exists primarily in wilderness areas. It primarily infects sheep and members of the canine family.