Can Snails Carry Disease? Snails may not be the cuddliest creatures in the world, but at least they are not as ugly as slugs, and they are harmless to humans, right? According to researchers at the University of California--Berkeley, snails can not only transmit dangerous parasites to humans, but snails are actually far more mobile than you probably assumed. In fact, researchers determined that freshwater snails can travel as far as thirty miles, which raises questions about the potential devastation freshwater snails could cause to human populations. Parasitic snails can spread the parasitic disease known as schistosomiasis. This disease affects more than two hundred and forty people worldwide. Just one single snail is enough to contaminate an entire water supply, and this is why the disease is so common in third world countries that struggle to procure fresh drinking water. According to researchers, human construction, and land clearing could be helping the parasite carrying snail travel greater distances. Freshwater snails have been known to ride leaves like rafts from one location to another. Researchers are currently studying the freshwater snail, along with a host of other disease spreading animals and insects, in order to develop new methods aimed at preventing the spread of animal-borne disease. Have you ever contracted an illness as a result of exposure to a disease carrying insect, or arthropod of any kind?