Story highlights Some hookworm larvae from contaminated soil or sand can burrow through human skin

The parasites generally go away on their own, but treatment can help

(CNN) Dozens of parasitic worms were found burrowing in the feet of a young Canadian couple after a recent trip to the Dominican Republic.

"We were scratching our toes for almost the duration of the trip," Eddie Zytner said.

Eddie Zytner and Katie Stephens returned home from vacation with itchy feet that turned painful.

Zytner, 25, and his girlfriend, Katie Stephens, 22, of Windsor, Ontario, returned home January 18 with itchy feet. Four days later, that itch turned into painful swelling and blisters, he said.

The pain became so intense that they could not tolerate shoes or socks and had to rely on crutches to walk.

Zytner shared a photo on his Facebook account that shows tortuous red tracks on his left foot.

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