Recent outbreaks of vaccine-preventable diseases in the United States have prompted clinicians, public health officials and the public to pay closer attention to the growing phenomenon of vaccine refusal. A new study looks at the role of vaccine refusal and the risk of measles and pertussis. In recent years, a substantial proportion of US measles cases occurred in people who were intentionally unvaccinated. Vaccine refusal was also found to be associated with an increased risk of pertussis in some populations.
