AP Photo

There has been a decline in vaccination rates in response to unfounded safety fears, but there's been a slightly different dynamic when it comes to one specific disease: whooping cough, caused by Bordetella pertussis. In areas where vaccination is erratic, like Africa, whooping cough is estimated to cause as many as 170,000 deaths annually, many of those in infants. However, in most developed nations, aggressive vaccination programs brought the disease under control by the 1970s. But, about a decade later, rates began to rise again, and there's been a bit of an argument over why.