People who get the shivers over tarantulas likely imagine a gigantic bite from a fanged mouth. But as one man recently found out in England, tarantulas are more likely to defend themselves by shooting a mist of microscopic barbed hairs straight into your eye.
At first, doctors were perplexed when the 29-year-old man came into their ophthalmologist's office at the St. James University Hospital in Leeds. The man didn't mention a run in with his pet tarantula.
"The patient came in with a red eye… and he already had a working diagnosis of conjunctivitis," said Dr. Zia Carrim, co-author of the case report who declined to identify the patient.
His eyes had been red and painful for three weeks, yet the usual rounds of medication for conjunctivitis (pink eye) had done nothing.
By the time he got to St. James, he was photophobic, meaning light hurt his eyes. Luckily Carrim's colleague, Dr. Jonathan Norris, decided to look at the patient with the highest magnification possible.
"He [Norris] was really surprised… when you had high magnification, he saw these tiny little protruding spots," said Carrim. "He said, 'I think this is really strange. I see really small hairs in your eye. I don't know what it is."
Finally, the patient remembered a strange incident while cleaning out the cage of his Chilean Rose tarantula.
"While his attention was focused on a stubborn stain, he sensed movement in the terrarium. He turned his head and found that the tarantula, which was in close proximity, had released 'a mist of hairs' which hit his eyes and face," wrote Carrim in the case report.
The man had no idea that those hairs were armed with barbs, which could help them penetrate into his eyes. Some barbs had already made it past his cornea, past his iris and to the back of the eye, called the retina.
Carrim said it would take a week after an attack for a person to feel symptoms. As the tiny hairs work their way into the eye with every blink, eventually the eye becomes painfully inflamed.
To make matters worse, the hairs were so small, doctors could not surgically remove them, so Carrim and his colleagues treated the patient with a round of steroids to flush them out.
Neither Carrim nor the patient knew that some tarantulas kick off urticating hairs when they are frightened.
Unfortunately, many pet shops do not tell owners, according to Cindy Steinle, who has adopted out more than 30 tarantulas in her Small Scale Reptile Rescue in Milwaukee, Wis.
"It's a defense technique. They [the hairs] are basically akin to little pieces of fiberglass," said Steinle, who noted rubbing hairs off the abdomen is often a tarantula's first line of defense, rather than biting.
Steinle says she keeps herself and her three pet tarantulas safe when cleaning her cages by putting a cup over the spiders. She never handles them and has never seen a tarantula shoot urticating hairs in her four years as a tarantula owner.
To learn more tips on caring for a tarantula, Steinle recommends a lot of research and visiting an online community such as insecthobbyist.com.
In her experience rescuing pets, she found many neighborhood pet stores do not always give out the best advice for exotic pets.
"Pet shops usually don't have a vast array of knowledge unless they are a specialty shop," she said.