Veterinary advice should be sought from your local veterinarian before applying any treatment or vaccine. Not sure who to use? Look up veterinarians who specialize in poultry using our directory listing. Find me a Vet

Eye Worm Infection

Other Names: Oxyspiruriasis

The eye worm, Oxyspirura mansoni is a species of roundworm which infects the chicken's eye. This parasite is mainly a problem for flocks living in the southern region of the United States (SC, GA, LA, MS, AL, FL, TX, AZ, and CA), and other tropical and subtropical areas worldwide. The eye worm is carried by the Surinam cockroach (Pycnoscelus surinamensis), which serves as an immediate host.

The eye worm is a small, thin white worm. It attaches itself in the corner of the chicken's eye, underneath the nictitating membrane. The presence of the worm causes the chicken extreme discomfort and impairs their vision. Infested birds are often seen continuously rubbing or scratching their eye. Without treatment, the chicken may end up scratching their eye, resulting in an infection, and/or eventual blindness.

Eye worm Life Cycle

Chickens become infected with the eye worm by eating its intermediate host--the Surinam cockroach (Pycnoscelus surinamensis), or exposure to other birds infected with the eye worm. Several wild birds serve as reservoirs including black birds, pigeons, bobolinks, blue jays, and loggerhead shrikes.

Once chickens eat the infected cockroach, the worm larvae hatch and migrate from the crop up to the esophagus to the mouth, through the nasal cavity, and into the eye. From there, the worm will grow into an adult and deposits its eggs in the chicken's eye. The worm eggs get passed down through the tear ducts, swallowed, and ejected from the body through their droppings.

Clinical Signs

Bird seen frequently scratching eye
Eyelids stuck together


  • History
  • Clinical signs
  • Physical exam

Reported Cases

  • Case 1: Eyeworm infection in a Chickens A few birds reared by a private owner as backyard poultry were brought to the Veterinary Dispensary, Thiruvanvandoor, with the complaint of inability to open the eyes. Irritation and secretion of tears from the eyes of birds were observed. White, small, thread like nematode worms recovered from the eyes, The worms were identified as Oxyspirura mansoni based on morphology. Ref


Supportive careIsolate the bird from the flock and place in a safe, comfortable, warm location (your own chicken "intensive care unit") with easy access to water and food. Limit stress. Call your veterinarian.
5% cresol solution1-2 drops placed in the lacrimal sac of the eye; followed by irrigation of the eye with sterile water to wash out remaining solution and any debris
Physical removal of the wormsPerformed by a veterinarian.
Solution of 0.5% iodine or 0.5% lysolAdministered into the eye with a syringe following applying a local anesthetic, 5% exylocaineVellayan et al., 2012.



  • Perform regular health checks on birds
  • Minimize risk of ingestion of cockroaches.
  • Minimize exposure to wild birds.

Scientific References

Risk Factors

  • Exposure to cockroaches.
  • Wild birds living on the premises where chickens are kept.