There’s some bad news for health officials in a new study that was presented this week at the Pediatric Academic Societies’ annual meeting. Even widespread outbreaks of infectious diseases may not be enough to convince vaccine-resistant parents to get their kids inoculated.
In order to reach those conclusions, researchers examined kids’ vaccination rates before and after Washington state’s record-breaking outbreak of whooping cough, also known as pertussis, in 2012. They expected to see an uptick in the number of kids getting their shots, particularly since public health officials were strongly urging more people to get vaccinated. But there was no change.
Whooping cough is particularly dangerous for small children, and can even be fatal. Even so, when comparing the percentage of infants who were up-to-date with their pertussis vaccination before and during Washington’s outbreak, there was no statistically significant difference between the two time periods.
“We have always assumed that when the risk of catching a disease is high, people will accept a vaccine that is effective in preventing that disease. Our results may challenge this assumption,” said Dr. Elizabeth Wolf, the study’s lead researcher and a fellow at the University of Washington, Seattle Children’s Research Institute, explained in a press release.
Researchers aren’t sure exactly why Washington residents remained resistant to vaccination. But previous research has found that it’s extremely difficult to change the minds of individuals who are opposed to vaccines. Like other deeply-rooted conspiracy theories, the idea that vaccines aren’t safe is difficult to challenge, despite the wealth of scientific research debunking it. “One possible explanation is that parents’ fear of adverse events still outweighed the fear of disease even in the face of an epidemic,” Wolf acknowledged.
Jenny McCarthy, an actress and model who has become the face of vaccine denial, exemplifies that point. She has famously furthered the myth that the vaccine intended to protect kids against measles, mumps, and rubella is linked to autism. “If you ask a parent of an autistic child if they want the measles or the autism, we will stand in line for the f–king measles,” she told TIME in 2009.
McCarthy isn’t the only parent who takes this view. An increasing number of Americans are following suit, allowing vaccine preventable diseases to start spreading again among pockets of unvaccinated people. Measles, mumps, and whooping cough are back with a vengeance in the United States. And there are other potential threats beyond these borders that could impact international travelers. Globally, the spread of polio now constitutes an “international health emergency.”