Could tapeworms be on the rise in city centres? There could be a growing urban tapeworm problem, reports Scientific American, citing a paper in the June issue of Emerging Infectious Diseases that reports on the spread of the salmon tapeworm. This worm, which can grow 12 metres long, and has been increasing in global distribution and prevalence, and appeared for the first time in North America and Europe in 2006. South American farm-raised salmon have also been plagued by a related tapeworm that normally goes after freshwater fish like perch. In another study in PLoS Neglected Tropical Diseases, researchers report that the fox tapeworm, a serious problem in Asia, has been expanding in Europe since the 1990s along with the urban fox population. It’s spread to humans in canine feces, and can cause fatal liver disease. To avoid getting a tapeworm from fish, it’s best to eat only fully cooked salmon, as heat destroys them, Scientific American reports. If raw fish is on the menu, though, choose tuna, which doesn’t spend time in rivers.