More children with whooping cough? Blame parents! 

The number of children in the U.S. coming down with pertussis, commonly known as whooping cough, is on track to be the worst outbreak in 50 years. As of August, 18,000 people had contracted the disease, nine of whom had died. The epidemic seems to be fueled by two causes: parents who refuse to get their kids vaccinated because of bogus concerns about autism and other alleged bad reactions, and a switch to a less potent vaccine more than a decade ago. The disease has hit particularly hard in states with relatively low childhood vaccination rates, such as Iowa, Vermont, and Washington. 

Worse, kids who have been vaccinated are coming down with the illness. Why? Because the diphtheria, tetanus, and whole-cell pertussis vaccine combo was altered in the late 1990s after some parents insisted that the vaccine had triggered side effects such as fever, irritability, and even brain damage. But the additional precaution also causes side effects: The immunity conferred by the new vaccine wears off faster, leaving kids vulnerable to the disease in their early adolescence. 

Now, thanks to the irrational fears of some parents, the population’s immunity has weakened to the point that physicians are recommending adults get booster shots since it is likely their immunity also has weakened over time.