Roundworm-Toxocara (Dogs and Cats)
Symptoms include: fever, cough, skin rash diarrhea, vomiting, pneumonitis and general icky feeling. With eye involvement there may be retinoblastoma, strabismus and blindness.
Roundworm-Thelazia (Eyes-from flies)
Thelaziasis is caused from Thelazia species of roundworms. This one likes the eyes. Flies feed on lacrimal secretions and inadvertently act as vectors in transferring the larvae into the eye. Symptoms include conjunctivitis (pinkeye) photophobia (sun sensitivity) and tearing. Corneal scarring can happen with chronic infection. You can actually see the worm move across the visual field.
Roundworm (Nematodes) Introduction
We were taught in our parasitology classes that if you took everything away from the world and left only roundworms, we would be able to see a perfectly formed planet kind of like a skeleton made of roundworms. There are that many roundworms in our soil.