Pet reptiles such as iguanas, lizards, snakes and turtles may carry Salmonella bacteria, which can cause salmonellosis in humans. The disease, characterized by diarrhea and fever in children, is transferred from the reptiles to humans through hand-to-mouth contact. "During the past year, 13 states, including California, have reported cases of reptile-related salmonellosis to the Centers for Disease Control and Prevention," says Art Craigmill, a UC Davis Cooperative Extension specialist in toxicology. "We encourage parents of children who have pet reptiles to make sure that children and adults thoroughly wash their hands after handling pet reptiles." The CDC also advises that people with weakened immune systems, such as those who are HIV-positive or undergoing chemotherapy treatment for cancer, are at high risk of contracting the disease. "The disease is avoidable by following the most simple hygienic procedure of hand-washing," says Craigmill.