India, Nov. 18 -- The long-debunked theory that childhood vaccines cause autism has returned to the spotlight, fueled by the rise of prominent anti-vaccine activists nearly three decades after its initial spread. Where did the "vaccines cause autism" theory come from? Dallas (tca/dpa) - In the late 1990s, a theory gripped parents around the world: What if childhood vaccines - particularly the combined measles-mumps-rubella vaccine - cause autism? Nearly three decades later, the debunked theory has gained renewed prominence in parallel with the rise of Robert F. Kennedy Jr., a long-time anti-vaccine activist who now serves as the US health secretary. Scientists, medical providers and medical researchers are clear on this: Vaccines do not cau...