Amid an ongoing measles outbreak in Oregon, state and local health officials are urging everyone to be vaccinated against measles, and especially for children to be up to date on their required vaccinations (including measles) before school starts.
The Oregon Health Authority held a press conference on Thurday to give an update on the outbreak, which began in mid-June. Dr. Paul Cieslak, OHA medical director for communicable diseases and immunizations, and Dr. Sarah Present, health officer at the Clackamas County Public Health Division, presented data and answered questions from the media.
Measles was declared “eliminated” in the U.S. in 2000, when only about 1% of kindergartners did not receive their required school vaccinations, including measles (through legal exemptions). This created substantial “herd immunity.” Over time, however, more and more parents have received exemptions for their children’s school vaccinations. For the 2023-2024 school year, 8.8% of Oregon kindergarteners received exemptions and did not receive all their required vaccinations.
The latest data show Oregon has the second-highest school vaccination exemption rate for kindergartners, behind Idaho.
“That is threatening our herd immunity,” Dr. Cieslak said. “The fact that we’ve seen such sustained transmission over two months means that we don’t have enough vaccinated people in the affected areas to stop the transmission, and so it goes on. As of now, we don’t see an end to it.”
Of the 25 measles cases reported this summer in Oregon, 24 live in Marion or Clackamas counties.
Measles is one of the most contagious diseases in the world, and it can be quite severe and even cause death. Infected people are contagious for about four days before they develop a rash, exposing others unknowingly. Two doses of the MMR vaccine against measles are safe and will provide 97% immunity.
Learn more about how to protect your children during a measles outbreak here. Find more resources and information at Boost Oregon.