Strands of parasitic worms found in dogs and cats are more likely to infect humans than other worm species, researchers said. monkeybusinessimages Getty Images/iStockphoto Strands of parasitic worms ...

Humans lost their hair because it reduced the number of biting and disease-causing parasites, and made them more sexually attractive, according to a new theory. Proposed by British scientists ...

Parasites live in other host organisms and depend on them for survival. Parasites that can affect humans include ticks, lice, and hookworms. Symptoms of a parasite infection in humans can vary widely.