A dangerous parasite is spreading north through Central America into the US, and its weakness may be a very specific smell

• Photo: CDC websiteA research project that quite literally involves studying stink may help protect livestock, pets and wildlife from one of the most destructive parasites in the Americas.
• At Colorado State University, professor Jessica Metcalf is investigating the foul-smelling chemical signals that attract the New World screwworm, a flesh-eating blowfly whose return to the United States has alarmed animal health officials.