The number of whooping cough cases in California jumped 61 percent in one year, from 1,023 in 2012 to 1,669 in 2013, according to a recent report from the California Department of Health. The majority of the sufferers? Kids between the ages of seven and 16, who made up 83 percent of cases.
Those number are all the more horrifying when you consider this: before it became somewhat more culturally acceptable to not vaccinate your kid, America had all but relegated pertussis to the waste bin of western diseases. The pertussis vaccine has been around since 1926, and was combined with the diphtheria and tetanus shots in 1948. (The shot was updated in 1999.)
As the vaccine spread, the rate of whooping cough cases plummeted. In 1955, according to CDC numbers, there were 62,876 reported pertussis cases in the U.S. In 1965, there were 6,799. We never completely eradicated the disease, but we kept the number of sufferers way down for nearly half a century.
That changed in the early 2000s, shortly after medical journal The Lancet published a (now-retracted) study saying that vaccines cause autism. Around the same time, the anti-vaccination movement in the U.S. was taking off. The result: 48,277 reports of whooping cough in the U.S. in 2012; the most since 1955.
While it's difficult to draw a straight line between the anti-vaccination movement and the increased number of cases of once-rare diseases, the California HealthCare Foundation reports that at the same time the state was dealing with the 2009 pertussis epidemic, the number of students who were enrolled in schools without their vaccines tripled.
If you need a visual aid, the Council on Foreign Relations and the Bill and Melinda Gates Foundation released in 2011 an interactive (and frequently updated) map of vaccine-preventable outbreaks across the globe. You can see the map below. Pertussis cases are in lime green, measles are in red, and mumps are that muddy green color: