Which American cities have lowest herd immunity due to anti-vaxxers?

Parents of Seattle, Spokane, Portland, Phoenix, Salt Lake City, Provo, Houston, Fort Worth, Austin, Plano, Detroit, Troy, Warren, Kansas City and Pittsburgh: beware.

According to a peer reviewed study of kindergartners whose parents had opted out of vaccination, these cities are the places with the lowest herd immunity to preventable, debilitating (and potentially fatal) diseases.

Vaccinations are not 100% effective, and some people can't be vaccinated due to illness. The reason vaccination keeps our children of dying or being maimed for life by the diseases that burned through generation after generation is "herd immunity": if all the kids get immunized, then the disease can't find enough people to infect and spread.

In a report published Tuesday in PLOS Medicine, researchers from several Texas academic centers tracked the increasing number of children with exemptions in all 18 states from the 2009-2010 to 2016-2017 school years. They characterized many rural counties, as well as urban areas, as "hotspots" because their high exemption rates put them at risk for epidemics of measles, whooping cough and other pediatric infectious diseases.

Idaho has eight of the top 10 counties with the highest exemption rates, the study found. In Camas County in southern Idaho, nearly 27 percent of the kindergarten population opted out of childhood vaccinations in the 2016-2017 school year, according to the study.

Generally, the 10 counties with the highest exemption rates have fewer than 50,000 people and are in rural areas.

Kids in these U.S. hot spots at higher risk because parents opt out of vaccinations [Lena H. Sun/Washington Post]