Recent increases in nonmedical exemptions (NMEs) to vaccination have created metropolitan “hotspots” with large numbers of unvaccinated children, according to a report published June 12 in PLoS Medicine.
although rates seem to have plateaued in some states since 2014. As a result of those increases, there were, during the 2016-2017 school year, 15 metro areas with kindergarten NME populations over 400, reported Jacqueline K. Olive, and her associates at Baylor College of Medicine. Their report was based on data from state health departments and the Centers for Disease Control and Prevention.
Leading the way was Maricopa County, Ariz., home of Phoenix and 2,947 unvaccinated kindergartners, which was more than triple the number in county/city No. 2, Salt Lake County/Salt Lake City (NME total: 956). Close behind in third was King County, Wash. (Seattle) at 940, followed by Multnomah County, Ore. (Portland) at 711 and Oakland County, Mich. (Troy) at 686, the investigators said.
[There was only room for 10 in the map, so here are hotspots 11-15: Wayne County, Mich. (Detroit); Allegheny County, Pa. (Pittsburgh); Travis County, Tex. (Austin); Jackson County, Mo. (Kansas City); and Spokane County, Wash. (Spokane).]
In addition to the large-population hotspots, there are also a number of mainly rural counties with smaller populations but high NME rates. Eight of the 10 highest such rates can be found in Idaho, and at the top of that list is Camas County, which had an NME rate of 27% in 2016-2017, the researchers reported.
Analysis of the relationship between NMEs and MMR vaccination showed that “states with more NME students exhibited lower MMR vaccination rates. In contrast, states that have banned NMEs – Mississippi, California, and West Virginia – exhibit the highest MMR vaccine uptake and lowest incidence of vaccine preventable diseases,” the investigators wrote.
Ms. Olive and her associates said that there was no specific funding for the study and that no conflicts of interest existed.
SOURCE: Olive JK et al. PLoS Med. 2018 Jun 12;15(6): e1002578. doi: 10.1371/journal.pmed.1002578.