Although not common in most parts of the U.S., it is possible for birds, especially wild birds, to become infected with eye worms. Eye worms also tend to infect captive chickens, mainly chickens that live in chicken houses that are infested with cockroaches. Let us explain. Cockroaches, particularly Surinam cockroaches eat bird droppings. In some cases, these bird droppings may be infested with worm eggs. The eggs hatch inside of the cockroach and become worms (larvae). The chicken or bird eats the infected cockroach. Once inside the chickens or birds body, the worm will migrate to the eye area, then deposit eggs into the eye. The worms migrate up the esophagi to the mouth through the tear duct, and into the eye. During this process, the bird swallows the worms. When the bird defecates, the larvae are expelled and the cockroach eats the droppings. Once the bird eats the cockroach, the life cycle of the eye worm starts all over again.
You may notice the worms swimming around underneath the eyeball of the bird or you may notice other symptoms of eye worms in birds or other animals. The eye may become inflamed and swollen. The eyelids may stick together and they may become watery or cloudy. The animal may be observed scratching vigorously to ease irritation.
Although eye worms are not too common in most states across the U.S., they can be found in southern parts of the U.S. as well as in Hawaii and in the Philippines. In many cases, these worms can be controlled by simply controlling the cockroaches, and in others, a topical anesthetic may be applied directly to the eye.
It is important to note that eye worms come in all shapes and sizes and humans can become infected, although humans are not the eye worms first choice and this is not likely to happen in the vast majority of developed countries. If you come in contact with a bird or animal with eye worms, just don’t touch it. The animals can leave an infection on your clothes or shoes, which can then be carried home with you.
About Eye Worms in Humans
Eye Worm: (species Loa loa), common parasite of humans and other primates in central and western Africa, a member of the phylum Nematoda. It is transmitted to humans by the deerfly, Chrysops (the intermediate host), which feeds on primate blood. When the fly alights on a human victim, the worm larva drops onto the new host’s skin and burrows underneath. The larva migrates through the bloodstream, commonly locating in the eye or in other tissues just under the skin. The adult worm is 3–6 cm (1.2–2.4 inches) long. The movement of the worm beneath the skin may cause itching or sometimes swellings as large as a hen’s egg. —From Encyclopedia Britannica
Encyclopedia Britannica Online Encyclopedia: www.britannica.com