Any new pandemic can come mainly from two possible sources: - mutation of an existing pathogen affecting humans - mutation of an existing animal pathogen so th

Any new pandemic can come mainly from two possible sources: - mutation of an existing pathogen affecting humans - mutation of an existing animal pathogen so that it can start infecting humans The first is more likely with inadequate treatment and lack of containment, the latter is more likely if there's more exposure of humans to the animal virus. With 130 million pigs infected with this disease there's quite a lot of exposure.