Kindergarten vaccination rates in Tennessee, a state once heralded for its childhood vaccination program, dipped to a record low of 93.7% in the past year, with Hamilton County falling among the least vaccinated counties in the state, according to a statewide report.
Six Tennessee counties -- Hamilton, Grundy, Van Buren, Maury, Fentress and Chester -- had fewer than 90% kindergartners fully immunized during the 2021-22 school year. Kindergartners in Hamilton County were 89.7% vaccinated, down from 91.6% the year before. Fentress County was the least vaccinated at 74.4%.
The figures come from an annual report conducted by the Tennessee Department of Health using data from public and private schools across the state, though 36% of private schools are not included because they did not complete the assessment. Homeschoolers and students enrolled in virtual learning only are also not included.
The growing number of kindergarteners missing required vaccinations means Tennessee communities are increasingly more susceptible to preventable diseases that at one time plagued the nation as school children across the state return for a new academic year.
Vaccination rates must remain above 95% -- a threshold that until 2021 Tennessee kindergartners consistently surpassed or nearly achieved -- to be at low-risk through herd immunity for highly infectious, vaccine-preventable disease outbreaks such as measles or pertussis, according to the report. Herd immunity occurs when enough people are immune to a disease through either vaccination or prior infection, and it's particularly important in order to protect people who cannot be vaccinated for medical reasons.
Polio is at risk of spreading if vaccination rates dip below 80-85%, according to Dr. Stephen Miller, health officer for the Hamilton County Health Department, who said in an email that while he's "not surprised" that vaccination rates are dropping, health department officials are "extremely concerned" that more families are opting not to vaccinate their children.
"These rates are similar to what we are seeing in the rest of the country," Miller said. "With the re-emergence of polio in New York and other developed nations, it's more prudent now more than ever to obtain these vaccines."
Since the COVID-19 pandemic, the number of Tennessee counties that meet the 95% fully immunized threshold decreased from 72 to 43 counties, representing a 40.3% decrease, according to the report. That means only 45% of Tennessee's 95 counties are at the 95% minimum threshold.