North Dakota Health and Human Services (HHS) is reporting five additional measles cases in Williams County, bringing the state’s total to nine cases in 2025. All newly confirmed individuals were unvaccinated and had no reported contact with previously identified cases. These individuals are currently isolating at home as recommended to help limit further spread.
Members of the public who were present at the following Williston location during the dates and times below may have been exposed. Those individuals are encouraged to monitor for symptoms and contact a health care provider if symptoms develop. Exposure location:
- Williston Walmart on April 29 between 2 p.m. and 5 p.m.
Four individuals diagnosed with measles were in Williston schools while infectious. In accordance with North Dakota Century Code 23-07-17, unvaccinated students should be excluded from school for 21 days following exposure. Staff without documentation of MMR (measles, mumps, rubella) vaccination or who were not born before 1957 should also be excluded. In addition to being excluded from school, all unvaccinated staff and children in these schools should remain at home and monitor for symptoms. Below is a list of affected schools and dates of exclusion.
Schools affected and dates of exclusion are as follows:
- Missouri Ridge Elementary: May 7 - May 23
- Williston Middle School: May 7 - May 21
- Williston High School: May 7 - May 21
HHS, in coordination with Upper Missouri District Health Unit, is working closely with the schools to notify families, provide education, and offer guidance.
"Due to the current measle outbreak, please isolate at home if you have symptoms of runny nose, fever, cough and rash,” said Dr. Beverly Tong, Upper Missouri District Health Unit deputy director. “Isolation should continue until at least four full days after the onset of a rash. Time from exposure to onset of rash is generally around seven to 21 days and you can spread measle up to four days prior to the time the rash appears. Please contact your health care provider's office if you wish to be tested, they will instruct you on when and where to arrive at their clinic to minimize risk to others."
Because some of the new cases are not linked to earlier known exposures, there is concern about potential community transmission. As a precaution, HHS recommends that all residents and travelers to Williams County ensure they are vaccinated against measles. This includes consideration of early MMR vaccination for infants aged 6 through 11 months. (Note: Infants under 6 months are not eligible for the vaccine.)
Early MMR vaccination is recommended for older children visiting or residing in Williams County as well. Children ages 12 months and older should receive their first dose of MMR if they have not already, followed by a second dose at least 28 days later. Children who have already received two post-12-month doses of MMR are considered fully vaccinated.
Adults born before 1957 are generally presumed immune due to natural exposure. Those born in 1957 or later living or visiting Williams County should ensure they have received two documented doses of MMR. Individuals unsure of their vaccination status are encouraged to consult their health care provider.
Immunization records can be reviewed at hhs.nd.gov/IRR or by contacting a provider. Vaccines are available through most clinics, and for families in need, the federally funded Vaccines for Children (VFC) Program offers support through local providers.
The Upper Missouri District Health Unit is holding vaccination clinics onsite at 110 W. Broadway in Williston on these dates at these times:
Location: at 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 urges anyone with measles-like symptoms, or who has been in close contact with infected individuals, should not arrive on site at the clinic and should reach out to their health care provider. Please call ahead before visiting a clinic or hospital emergency room to avoid exposing others.
For information about measles, vaccination, or local clinic availability, contact the HHS Immunization Unit at 701-328-2378 or 711 (TTY), or visit hhs.nd.gov/measles.