GREAT FALLS — On Tuesday, July 15, 2025, the City-County Health Department (CCHD) in Great Falls was notified of Cascade County’s first measles case.
According to a news release from CCHD, the individual resides in Cascade County and is a reported vaccinated adult. Their vaccination status has not been confirmed at this time, and the source of exposure remains unknown. The individual is currently isolating at home.
The CCHD is continuing to assess any potential exposures while the individual was contagious and may be contacting people known to be exposed.
The agency has determined that there are points of exposure to the general public. Potential exposures to the public can be found on the Cascade County website and will be updated as more information becomes available.
The spread of measles can occur before people know they have the disease and before any rash appears. The times listed on the website include the period when the exposure occurred and two hours after, which is how long the measles virus can remain airborne.
Growing concerns over measles exposure in Great Falls:
People who are immune to measles through vaccination, laboratory evidence of immunity, laboratory confirmation of disease, or were born before 1957 are not considered at risk for infection.
Individuals without prior measles infection or vaccination have a 90% likelihood of contracting the disease if exposed.
Measles is a highly infectious airborne disease that typically begins with a fever, cough, runny nose, red eyes, white spots in the mouth, and a red rash that appears about 14 days after exposure. The rash usually starts on the face and spreads downward to the rest of the body. It is particularly dangerous for infants for whom vaccination is generally not recommended until 12 months of age. Maintaining a high level of vaccination in the community helps protect infants who are too young to be vaccinated, as well as individuals who cannot be vaccinated for medical reasons.
Measles continues to be prevalent in many regions worldwide, resulting in an estimated 300 deaths every day. This month, the federal Centers for Disease Control & Prevention (CDC) reported the highest number of measles cases in the United States since the disease was declared eliminated in 2000. As of July 8, 2025, there were 1,288 reported measles cases in 39 states. Montana has had a total of 26 cases of measles reported in four other counties in addition to Cascade County.
The best way to protect against measles is vaccination. No changes have been made to the existing measles, mumps, and rubella (MMR) vaccine recommendations in the United States. Two doses of MMR, a measles-containing vaccine that protects against measles, mumps and rubella, are 97 to 99 percent effective in preventing measles. Measles vaccines have been available in the U.S. since 1963, and two doses have been recommended for children since 1989.
If you are not sure of your vaccination status, here are a few places you can review:
- Call your old high school, college, or university and ask if they have vaccination records.
- Contact your doctor’s office, urgent care, or pediatrician. Even if you have not been there in years, they may still have your records.
- Contact the health department where you grew up.
- Check your home state immunization registries.
If you need the MMR vaccine, call your primary care physician as soon as possible. CCHD does have MMR vaccine available. Please call 406-454-6950 to make an appointment.
For more information about measles and the measles vaccine, visit the state health department’s website. Additional information can also be found on the CDC’s website.
If you develop symptoms, you should continue to stay home except for testing or urgent/emergency treatment. Please call your healthcare provider or urgent care to arrange for testing. It is extremely important that you do not enter a clinic building without calling ahead to the clinic so that precautions can be taken to avoid exposing others.
CCHD has a measles phone line at 406-791-9242. Please call this number for:
- Healthcare provider reports of measles cases or suspected cases
- Immunization questions, record checks, or appointments
- Testing information
- Questions about exposure or quarantine
- Any other measles questions or concerns
This phone line is operated during business hours – if you call outside normal business hours and leave a message, we will contact you the following business day.
