Updated, 12:30 p.m. Monday
Earlier this week, a slew of articles published reporting new research that identified 15 metro “hotspots” at risk for outbreaks of pediatric infectious diseases — and Pittsburgh was on the list.
But data used for Allegheny County was incorrect, causing researchers to wrongly deem Pittsburgh as a top location for kindergarteners with nonmedical exemptions for vaccines.
The Texas researchers apologized in a letter to the Pa. Department of Health for the error on Friday, and the Allegheny County Health Department stressed that the nonmedical exemptions are not significantly increasing.
The article, “The state of the antivaccine movement in the United States: A focused examination of nonmedical exemptions in states and counties” by a team from the Baylor College of Medicine was published Tuesday in PLOS Medicine, an open-access medical journal. It included a list of 15 metro locations that had the most exemptions and were also in counties with more than 400 exempt kindergartners. While much of the data was from 2016-17, the data for Allegheny County was from 2015-16.
On Thursday, Dr. Karen Hacker, director of the Allegheny County Health Department told The Incline that the data used didn’t match state and county data for the same year— in fact, it was double the state’s numbers.
Per the PLOS Medicine article, Allegheny County was incorrectly listed as having 424 kindergartners with nonmedical exemptions for vaccines in the 2015-16 school year. However, the Pa. Department of Health and the Allegheny Health Department have different totals for the same data:
- Per the state, it was 212 kindergartners
- Per the county, it was 236 kindergartners
Hacker said the slightly higher county number is because the county follows up with late reporting schools to update the data.
The Pa. Department of Health contacted the Baylor researchers about the discrepancy on Thursday, prompting a review of the data, per a news release from Baylor.
On Friday, two of the researchers, Peter Hotez, dean of the National School of Tropical Medicine at Baylor and Melissa S. Nolan, faculty at Baylor and the University of South Carolina, sent a letter to the Pa. Department of Health. In it, they said there was an error in their Pa. data and they were requesting the article be changed.
Read the letter here:
The Pennsylvania data was “inadvertently doubled during data analysis” however the review found that data from other states was correct, according the Baylor press release. The researchers updated their list of 15 metro “hotspots,” removing Pittsburgh and adding Tacoma, Washington.
“We are now implementing a double-data entry check system to prevent this from occurring in the future and appreciate that the Pennsylvania State Department of Health brought this to our attention,” Hotez said in the release.
Pennsylvania is one of 18 states that allows for nonmedical exemptions, and Hacker stressed there has been no significant change in recent years for nonmedical exemptions to vaccination in Allegheny County in kindergarteners.
Here’s the data for four school years, per the county:
- 2014-15 — 322 kindergartners (2.4 percent of enrolled kindergartners in the county)
- 2015-16 — 236 kindergartners (1.8 percent)
- 2016-17 — 300 kindergartners (2.4 percent)
- 2017-18 — 267 kindergartners (2.1 percent)
Nonmedical exemptions are religious and philosophical exemptions combined, meaning they are based on the views and opinions of parents, explained Dr. Wilbert van Panhuis, an epidemiologist at the University of Pittsburgh Graduate School of Public Health.
Additionally, children can also get medical exemptions to vaccines. These are the kids who are immunocompromised and extremely vulnerable, such as children on chemo or steroids and kids with HIV or AIDS. It’s not children with the flu, he stressed.
And kids with medical exemptions are the ones who are most at risk, especially if they are around kids who have nonmedical exemptions, he said, adding vaccines help to prevent illnesses that are highly contagious such as measles where one infected child can give it to 12 others. That’s compared to the flu, where one kid with the flu will likely give it to one other kid, he said.
Tracking the numbers
The Allegheny County Health Department releases school immunization reports that include breakdowns by type of school (public, private, so on) and grade, but not by specific school.
However that’s something that the Public Health Dynamics Lab at Pitt and the county health department are working on, said van Panhuis and Hacker.
It’s likely that the kids with nonmedical exemptions aren’t evenly distributed throughout the county, van Panhuis said, adding that means there are are some schools with higher concentrations of non-vaccinated students.
There’s some hesitancy to release the immunization details by school, but it’s not about blame, van Panhuis said. Instead, it’s about making that information available to parents and pointing out where the risk is.
A previous version incorrectly listed the full name of the Baylor College of Medicine.