Increase in Measles Cases in North Dakota

BISMARCK, N.D. – North Dakota Health and Human Services (HHS) has reported five new cases of measles in Williams County, which raises the state’s total to nine cases for the year 2025. It’s worth noting that all the newly confirmed cases involve individuals who were not vaccinated and had no recognized contact with previously diagnosed patients. These people are currently following isolation guidelines at home to help prevent further transmission.

Previous Coverage: UPDATE: Three more measles cases confirmed in North Dakota

People who were at a specific location in Williston during the dates listed below may have been exposed. It is recommended that they monitor for symptoms and to reach out to a healthcare provider if any develop.

Exposure location:

• Williston Walmart on April 29 between 2 p.m. and 5 p.m.

Four of the diagnosed individuals were present at Williston schools while being infectious. Following North Dakota Century Code 23-07-17, unvaccinated students must stay out of school for 21 days after potential exposure. Additionally, staff without documentation of MMR (measles, mumps, rubella) vaccination, or those born after 1957, should also be excluded. All unvaccinated staff and children in these schools should stay home and monitor for symptoms. Below is the list of affected schools and their exclusion dates.

Affected schools and exclusion dates:

• Missouri Ridge Elementary: May 7 – May 23
• Williston Middle School: May 7 – May 21
• Williston High School: May 7 – May 21

HHS is collaborating with the Upper Missouri District Health Unit to inform families, provide education, and offer advice.

“Due to the current measles outbreak, please isolate at home if you experience symptoms such as a runny nose, fever, cough, and rash,” advised Dr. Beverly Tong, deputy director of the Upper Missouri District Health Unit. “Isolation should continue until at least four days after a rash starts. The time from exposure to the onset of a rash is usually between seven to 21 days, and measles can be contagious up to four days before the rash appears. If you need to be tested, please contact your healthcare provider for instructions on minimizing risk to others.”

As some new cases don’t seem to be linked to earlier exposures, there’s rising concern about potential community transmission. HHS advises all residents and visitors to Williams County to ensure they are vaccinated against measles. This includes considering early MMR vaccination for infants aged 6 to 11 months, although infants under 6 months aren’t eligible for the vaccine.

For older children visiting or living in Williams County, early MMR vaccination is also recommended. Kids aged 12 months and older should get their first dose of MMR if they haven’t, followed by a second one at least 28 days later. Those who have already received two doses past age 12 months are fully vaccinated.

Adults born before 1957 are generally considered immune due to natural exposure. Those born in 1957 or later should confirm they have received two documented MMR doses if living in or visiting Williams County. Anyone uncertain about their vaccination status is encouraged to check with their healthcare provider.

Immunization records can be reviewed at hhs.nd.gov/IRR or by contacting a provider. Vaccines are available at most clinics, and the federally funded Vaccines for Children (VFC) Program helps support local providers for families in need.

The Upper Missouri District Health Unit is offering vaccination clinics at 110 W. Broadway in Williston on the following dates and times:

Location: 110 W Broadway in Williston

Hours:

• Thursday, May 8 from 1 to 7 p.m.
• Friday, May 9 from 8:30 a.m. to 6 p.m.

*HHS strongly advises anyone with measles-like symptoms, or who has been in close contact with infected individuals, to avoid the clinic and reach out to their healthcare provider. Please call ahead before visiting any clinic or emergency room to prevent exposing others.

If you need information about measles, vaccination, or local clinic availability, you can contact the HHS Immunization Unit at 701-328-2378 or 711 (TTY), or visit hhs.nd.gov/measles.