How to Protect Yourself and Your Family from the Measles Outbreak in Oregon: Tips from a Top Immunologist

The measles outbreak that began in mid-June in Marion County has now spread to at least 23 residents across three counties. The situation is far from over, according to Dr. Paul Cieslak, the Oregon Health Authority’s top immunologist. "We continue to see cases, and we have not been able to connect them all, suggesting that there are other cases out there,” he remarked ominously.

Among those infected, only one person was vaccinated, and two have been hospitalized. Alongside measles, pertussis or whooping cough cases are also rising, with seven new cases reported last week, bringing this year's total to over 400 across 13 Oregon counties.

With the school year approaching, the health authority is urging parents to ensure their children are up-to-date on vaccinations. Measles and whooping cough vaccines are mandatory for the nearly 550,000 children attending school in Oregon, though non-medical exemptions can be obtained by watching an online training module or consulting with a provider.

Dr. Cieslak emphasized the effectiveness of the measles vaccine: one dose is 93% effective, and two doses are 97% effective. Unlike viruses like COVID-19, the measles virus does not mutate significantly, maintaining the vaccine's efficacy.

In 2000, the World Health Organization declared measles eradicated in the U.S., but due to international travel and unvaccinated individuals, it has resurfaced. This year marks the highest number of cases in Oregon in several years, with only one case last year and none in the previous three years.

Oregon has one of the highest unvaccinated rates in the country. As of May, nearly 9% of the state’s kindergartners had a non-medical exemption, up from 8% in 2023 and 7% in 2022, marking a steady increase.

The outbreak began in June, when an adult in Clackamas County developed a rash, followed by a child falling ill. The virus quickly spread among unvaccinated children. Currently, there are eight cases in Clackamas County, 13 in Marion County, and two in Multnomah County. Among the infected are 10 children under 10, eight teenagers, and five adults.

Measles, a highly contagious virus, spreads through the air when an infected person coughs or sneezes, and the particles can linger for two hours. Symptoms include flu-like signs and a rash that starts on the face and spreads. Complications can include ear infections, pneumonia, diarrhea, brain swelling, and in severe cases, death. Nationwide, nearly 50% of measles patients have been hospitalized, mainly to prevent further spread.

Those most at risk include unvaccinated pregnant women, infants under one year, and individuals with weakened immune systems. Whooping cough, another concern, is also on the rise, nearing pre-pandemic levels. Lane County has reported the highest number of cases in Oregon this year, followed by Multnomah and Clackamas counties.

As the situation evolves, the health authority continues to monitor and respond to the outbreak, emphasizing the importance of vaccinations to protect against these preventable diseases.