Measles outbreak in Oregon continues to spread

The measles outbreak that started in mid-June in Marion County has spread to at least 23 residents in three counties.

And it’s probably not over.

“We continue to see cases, and we have not been able to connect them all, suggesting that there are other cases out there,” said Dr. Paul Cieslak, the Oregon Health Authority’s medical director and top immunologist.

Only one person in the outbreak has been vaccinated and two people have been hospitalized, the health authority said.

Cases of pertussis or whooping cough also are spreading, with seven cases reported last week, bringing the year’s total to more than 400. The virus has infected people in 13 Oregon counties this year.

With the start of the school year looming, the health authority urged parents to get their kids up to date on their vaccinations.

Measles and whooping cough vaccines are required for the nearly 550,000 children attending kindergarten through high school in Oregon, though parents can obtain a non-medical exemption if they watch an online training module or talk to a provider and have them sign a certificate.

Cieslak said the measles vaccine is particularly effective: One dose is 93% effective at preventing an infection and two doses are 97% effective.

The measles virus does not mutate significantly the way other viruses like COVID do, Cieslak said.

In 2000, the World Health Organization said it was eradicated in the U.S. But with foreign travel and unvaccinated people, it’s re-emerged. This is the highest number of cases in Oregon for several years. There was only one case last year and none the previous three years, state data shows.

Oregon has traditionally had among the highest unvaccinated rates in the country. In May the health authority said that nearly 9% of the state’s kindergartners had a nonmedical exemption this year, forgoing at least one required shot. That compares with about 8% in 2023 and almost 7% in 2022, marking the second consecutive yearly increase in the unvaccinated rate.

Besides Oregon, there are nearly 170 measles cases in other states, according to the federal Centers for Disease Control and Prevention.

The outbreak emerged last month. The Oregon Health Authority reported that an adult in Clackamas County developed a rash on June 11 and that a child subsequently got sick as well.

More cases appeared among unvaccinated children who apparently had not been in contact, health officials said. To date, there are eight cases in Clackamas County, 13 people in Marion County and two in Multnomah County, with 10 younger than 10 years, eight teens and five adults.

The disease is highly infectious. It spreads in the air when someone coughs or sneezes and the viral particles can linger in the air for two hours. Symptoms can begin up to three weeks after exposure and can include flu-like symptoms and a rash that appears on the face and spreads to the rest of the body. Patients can develop ear infections, lung infections and diarrhea. The disease can also cause swelling of the brain and be fatal. One of two of every 1,000 cases are fatal.

Two of the people infected in Oregon have been hospitalized. The health authority did not provide any more information about who they were or how severe their symptoms were or whether they’ve been discharged. Nearly 50% of people with measles across the country have been hospitalized this year, sometimes to prevent them from spreading the virus, the CDC said. Eighty-five percent were not vaccinated.

People who are pregnant and not vaccinated, infants younger than 1 and those with weakened immune systems face the greatest health risk from measles and whooping cough.

Whooping cough is more prevalent than measles, with 10,000 cases reported nationwide before COVID hit. During the pandemic, cases dropped as people tried to avoid respiratory infections. But they’re now on the rise, approaching pre-pandemic levels, the CDC said.

In Oregon, Lane County has had the most cases this year – 123 – followed by 77 in Multnomah County and 57 in Clackamas. Cases peaked this year in May, with 115 reported. That dropped to 92 in June.

https://oregoncapitalchronicle.com/2024/08/02/measles-outbreak-in-oregon-continues-to-spread/

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