“What we’re trying to do is identify what are the areas that are most likely to be affected by this [anti-vaccination] movement that’s happening,” said study co-author Lauren Gardner, an associate professor in the Department of Civil Engineering at Johns Hopkins University.
“These outbreaks can only happen if someone brings measles into the country and there’s a low vaccination rate in a population,” Gardner explained.
“The places where measles outbreaks are happening this year were the ones that we ranked really highly in our risk model,” which had largely been completed by February, she added.
According to the paper, of at least 45 counties reporting measles cases this year, 30 were among or adjacent to the researchers’ top 25, including outbreaks in states like New York, Washington and Oregon.
The new paper isn’t the first that has tried to predict outbreak risks in the United States, but previous efforts did not include international travel, Gardner said.
“What’s going to happen as we move into the summer months, with all that back-and-forth travel between Europe and the US … there’s opportunities to introduce a lot more measles into this country,” said Dr. Peter Hotez, dean of the National School of Tropical Medicine at the Baylor College of Medicine.
“That’s an all-star batting average in Major League Baseball,” said Hotez, who was not involved in the new paper but whose previous study was one of its data sources.
The latest paper — “version 2.0,” he called it — looks at the entire country and picks up hot spots that his analysis missed.
“That’s something we could never have predicted.”
In the new model, Queens — which is adjacent to Brooklyn, one of the focal points of the ongoing New York measles outbreak — is ranked fourth.
A total of 47 states allow nonmedical vaccine exemptions: all but West Virginia, Mississippi and California. Some allow only religious exemptions, while others allow exemptions based on personal or philosophical beliefs.
Hotez said that these maps can help target public health vaccination efforts where they’re needed most. But he said the maps shouldn’t just be coming from academics like himself; he believes they should be generated every year by public health agencies like the CDC.
“It’s the consequence of allowing the anti-vaccine movement to run unopposed for so many years.”
CNN’s John Bonifield contributed to this report.