evidence: Data via the Centers for Disease Control and Prevention 1998 In a paper that was later retracted and discredited, British researcher Andrew Wakefield questions the safety of the MMR vaccine in Lancet, claiming a connection between immunization and autism. The report receives widespread media coverage. Immunization rates in the United Kingdom plummet in the years after, and the discredited study inspires vaccine hesitancy across the Western world. Investigations would later reveal that Wakefield had been paid by a lawyer working on a lawsuit against the vaccine producer. Several follow-up studies have failed to find a link between autism and the MMR vaccine. Infographic by Vanessa Dennis 2000 Measles is declared eliminated from the U.S., meaning continuous transmission of the disease has not occurred in the country for more than 12 months. 2011 Measles cases surpass 200 for the first time since elimination, driven by U.S. travelers catching the disease overseas. Measles breaks out in European countries — namely France, Italy, Romania, Spain, and Germany — and ultimately spreads across the continent. 2014 The U.S. records 667 measles cases across multiple outbreaks caused by imports, mostly from the Philippines, raising concerns about the integrity of herd immunity.