Oregon health officials have declared a measles outbreak following the confirmation of five cases in the state as of March 15, 2024. During a virtual press conference, Dr. Howard Chiou, the medical director for communicable diseases and immunizations at the Oregon Health Authority’s Public Health Division, emphasized that these confirmed cases likely represent only a small fraction of actual infections.
“What I really want families to hear is that measles is here in Oregon,” Dr. Chiou stated. He urged families to reconsider their vaccination decisions and consult health care providers to ensure adequate protection against the disease.
Wastewater Surveillance Indicates Broader Spread
A new data dashboard released by the Oregon Health Authority demonstrates the spread of the measles virus across various counties, utilizing wastewater surveillance methods. Samples from community sewage systems have detected traces of the measles virus in several areas, including Lincoln, Marion, and Multnomah Counties. The confirmed cases, however, have been primarily located in Clackamas and Linn Counties.
According to state data, low levels of the virus have been found in multiple regions, indicating a potential increase in cases if vaccination rates do not improve. The recommended protocol for measles vaccination involves two doses of the measles-mumps-rubella (MMR) vaccine, starting at 12 months of age, with a second dose administered between the ages of 4 and 6. The American Academy of Family Physicians notes that approximately 97% of individuals who receive both doses develop immunity to measles.
Complications and Community Impact
While breakthrough infections are rare among vaccinated individuals, measles is highly contagious, particularly among unvaccinated people. According to health officials, around 90% of susceptible individuals in close contact with a contagious measles patient will contract the virus. Of the five confirmed cases in Oregon, four individuals were not vaccinated, while the vaccination status of the fifth remains unknown.
Dawn Nolt, an infectious disease doctor at Doernbecher Children’s Hospital, underscored the severity of the disease. “Measles is not just a fever and a rash. All children who get measles are absolutely miserable,” she explained. Symptoms may appear up to three weeks after exposure and can include fever, flu-like symptoms, and a distinctive rash that spreads across the body.
Nearly one-third of those infected with measles experience complications, such as ear infections, pneumonia, and encephalitis, which is swelling of the brain. The disease can also weaken the immune system, making it more difficult for patients to combat other infections for months or even years after recovery.
Measles spreads through respiratory droplets when an infected individual speaks, sneezes, coughs, or breathes, and it can linger in the air for up to two hours.
Oregon health officials aim for a 95% vaccination rate to effectively limit the spread of the disease and protect those unable to be vaccinated, such as infants, through herd immunity. Children attending public schools in Oregon are required to be vaccinated against measles, along with other diseases including diphtheria and polio. However, the state has struggled to meet this vaccination goal due to the prevalence of medical and non-medical exemptions.
Data from the previous year indicated that 93.5% of kindergarteners in Oregon had received their first dose of the MMR vaccine, while 90.5% had completed both doses. Notably, the rate of non-medical vaccine exemptions reached its highest level, with nearly 10% of kindergarteners receiving exemptions for non-medical reasons for one or more required vaccines.
As the situation develops, health officials continue to advocate for increased vaccination efforts to mitigate the outbreak and protect vulnerable populations.
