State health officials warn of declining vaccination rates in Oregon schools

Oregon's kindergarten vaccination rates have fallen to a new low for the 2025-2026 school year. This coincides with record high nonmedical exemptions for required school vaccines. This decline raises concerns among state health officials about the potential return of preventable diseases like measles and polio.

For the 2025-2026 school year, nonmedical exemptions for required school vaccinations among Oregon kindergarteners reached a record high of 10.9%, an increase from 6.9% in the 2021-2022 school year. Data shows only 85.6% of kindergarteners were up to date on required vaccines, continuing a decade-long downward trend.

The vaccine with the highest rate of nonmedical exemptions for kindergarteners is the second dose of the measles vaccine, known as MMR, at 9.4%. This marks a 92% jump from 4.9% a decade ago. measles is considered one of the most contagious diseases in the world and vaccination is the most effective way to prevent infection.

Dr. Howard Chiou, medical director for communicable diseases and immunizations at the Oregon Health Authority Public Health Division, stated that "Although the vast majority of families in Oregon are still choosing to protect families through vaccination, the downward trends are deeply concerning. We risk seeing the return of diseases such as measles and polio—diseases of the past that once caused widespread harm but are entirely preventable with vaccines."

The DTaP vaccine, which protects against diphtheria, tetanus and pertussis, has the second highest rate of kindergarten nonmedical exemptions. Pertussis, also known as whooping cough, saw 1,475 cases in Oregon during 2025.

While 90.2% of K-12 students statewide are up to date on required vaccinations, individual schools still face pockets of risk across all 36 counties in Oregon. State health officials urge parents and guardians to check their school's vaccination rate to understand the local risk of a disease outbreak.

"Even when overall vaccination rates are high at the state or county level, that can sometimes hide significant risk at an individual school, so parents should not assume their local schools will also be well protected," Dr. Chiou said. "We encourage families to look at the immunization rates for their child's school to better understand personal and community risks."

To prevent or limit the spread of measles infections, the American Academy of Pediatrics states that 92% to 94% of the population needs to be immune through vaccination or previous infection. Oregon's public health system strives for a 93% vaccination rate to achieve herd immunity.

Currently, more than one in three, or 36%, of Oregon schools with 10 or more students in grades K-12 report MMR vaccination rates below 93%. These schools are considered at high risk of a measles outbreak. Parents and caregivers can see vaccination rates for individual schools on OHA's School Immunization Data dashboard.