Idaho health officials confirm third measles case in unvaccinated child, suggesting higher spread

BOISE (Idaho Capital Sun) — Idaho reported the state’s third measles case in the last two weeks, after not reporting any infections this year during a national surge. 

Health officials say they don’t know of a link between the new measles case in Bonner County reported Wednesday and a separate case reported last week in Kootenai County, which are both in North Idaho. That means measles is likely spreading more, said Dr. Christine Hahn, Idaho’s state epidemiologist.

“Without any link between these two confirmed cases in north Idaho or travel outside of their communities, it’s reasonable to suspect that there is more measles circulating,” Hahn said in a statement. “As we’ve seen with other states around the nation, cases can begin to multiply quickly.” 

Idaho’s three measles cases are all in unvaccinated children. Vaccination is the best way to prevent measles, which is highly contagious and usually leads to hospitalization for one in five children younger than 5 years old who are infected. 

Last week, eastern Idaho health officials confirmed a measles case in Bonneville County.

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But officials said they didn’t think the public was exposed. 

In both regions of Idaho that have seen measles cases this year, the infections are the first reported in more than three decades and came shortly after early signs of the virus locally. Idaho hasn’t reported local measles cases since 2023, when an outbreak in southwest Idaho led to 10 infections.

The U.S. is experiencing the worst outbreak of measles in decades. This year, health officials have confirmed 1,375 measles cases across 41 states by Tuesday, according to the Centers for Disease Control, or CDC. About 13% of measles cases in the U.S. this year led to hospitalizations, the CDC reports. 

Officials encourage people to verify vaccination records

Measles is highly contagious but rare. Up to 90% of non-immune people in contact with an infected person can become infected. The virus can live in the air up to two hours after someone infected leaves.

Symptoms typically appear seven to 14 days after exposure and include high fever, cough, runny nose, red eyes, and a distinctive rash, the CDC says. While many recover without problems, measles can lead to serious complications, especially in very young children and people with weakened immune systems.

Health officials encourage people to verify their family’s vaccination records with their primary care provider or through the Docket App. A person is considered immune if they were born before Jan. 1, 1957, have a documented history of laboratory-confirmed measles or have documentation that they received both doses of the MMR vaccine. 

Idaho has a spotty record for measles vaccinations, the Idaho Capital Sun previously reported. 

The virus’s serious complications can include pneumonia, encephalitis (an inflammation of the brain) and, in rare cases, death.

People with measles symptoms should not enter health care settings without calling ahead, and they should contact their health care providers. People exposed to measles should monitor for symptoms for 21 days after exposure.

There is no antiviral treatment for measles, according to the CDC.