These tusked omnivores are more widespread in the U.S. than ever before. European explorers and settlers brought them to the New World as early as the 1500s. Today, around six million feral swine run hog wild in at least 35 U.S. states, where they grow more than five feet long and weigh more than 500 pounds. What's more, the females can begin reproducing at just eight months of age, and each produce up to two litters of four to twelve piglets every twelve to eighteen months.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                Feral swine also ravage agricultural crops, and can harm people who corner them. But those outcomes aren't what really worry experts. It is their diseases. According to the USDA, fwral swine can carry a litany of pathogens that could potentially spread to people such as leptospirosis, toxoplasmosis, brucellosis, swine influenza, salmonella, hepatitis, and pathogenic E. coli. But there's another concern -- new diseases we don't even know about yet. By far, U.S. health officials are more worried about African swine fever, a virus that first originated in 1921 but has since reemerged in various countries worldwide. Though not transmissible to people, the disease is always fatal to pigs, either wild or farmed, says Vienna Brown, a USDA staff biologist with the agency's National Feral Swine Damage Management Program.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         Were the virus to infect feral swine in the U.S., it could then spread to and devistate the U.S. pig industry, currently the world's third largest producer of pork. In China, farmers were forced to kill more than 43 million pigs to stop the virus' spread in 2018. In 2007 and 2008, at least three people in the eastern U.S. contacted brucellosis after hunting feral swine, according to the CDC. As omnivores with the ability to tear up soil like a rototiller, feral swine cause an estimated $2.5 billion in damages to U.S. crops, pastures, forests, and livestock each year.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       "Places like Florida, California, Oklahoma, Texas -- their populations are so big and so widespread... eradication is not really the goal at this point," says Brown. "It's about damage management."