Vaccination rates in some K-12 schools are too low to guarantee herd immunity. How did central and western Oregon schools fare?
State health experts say their goal is to keep schools above 90% up-to-date on vaccinations. But many now fall short of that number.
The vaccination rates in Oregon schools continue to drop, reaching an average of 90.2% as non-medical exemptions continue to rise around the state. However, a public health official said the numbers vary widely from school to school.
Howard Chiou, the Medical Director of Communicable Diseases and Immunizations at the Oregon Health Authority, said the number is getting close to 90%, the number that OHA sets as its goal to prevent the spread of preventable diseases.
"What’s alarming to me is that around 40% of schools currently don’t meet [90%],” said Chiou. “So even though the vast majority of students are up to date, the variation between schools and counties can be really concerning."
While 90% covers many of the diseases covered by routine vaccinations, the rates can vary.
Chiou gave an example of measles, which requires a 93% vaccination rate to maintain herd immunity. He said that about a third of Oregon schools fall below the measles herd immunity threshold.
“Families should understand that the situation has changed here in Oregon and in the United States,” he said. “They really should make decisions that are informed by data.”
Rates vary widely in western and central Oregon
In western and central Oregon, half of the counties have rates above the 90% goal mark Chiou mentioned.
The counties that exceed the target are Lane (91.3%), Lincoln (92.1%) and Benton (91.3%).
Vaccination rates in Deschutes (88.4%), Douglas (88.5%) and Linn (89.8%) counties all fell below the mark.
K-12 schools have a similar breakdown, with nearly half of all schools meeting the goal. 171 of 374 fall below it.
While county numbers are all within four percentage points, data show that nine schools in the area have 100% vaccination rates, while eight fail to reach 50%.
The 30 schools with the lowest vaccination rates were private or charter schools, and most had religious affiliations or followed Montessori or Waldorf education philosophies.
Top schools were more varied with alternative and religious schools making up all of the 100% vaccination rates, and a mix of public, private and charter schools following thereafter.
How did various schools fare? Here’s the data:
