BOZEMAN — Two more cases of measles were confirmed in Gallatin County on Thursday, June 19.
This brings the total number of cases reported by Gallatin-City County Health to 14. A previous case, reported on June 14th, was a person visiting from out of state and is no longer being counted in Gallatin County's count. The health department says this case will be attributed to the individual's home state numbers.
The two cases, both affecting children under the age of 17, confirmed Thursday, were reportedly household exposures from a previous case. Presently, 9 children and 5 adults in Gallatin County have made up the total cases.
According to DPHHS, on June 11, 2025, the Gallatin City-County Health Department issued an accelerated administration schedule consideration for Measles, Mumps, and Rubella (MMR) vaccine for all residents and visitors due to recent confirmed cases of measles in the Gallatin community. The considerations include early and accelerated vaccination for children and an additional MMR dose for adults who have received one dose. More information can be found by visiting the Gallatin City-County Health Department measles page.
Measles is highly contagious, spreading rapidly among those without immunity. According to the Montana Department of Health & Human Services (DPHHS), “If somebody with measles walks into a room, 90% of people who have no immunity to it will get infected.”
Vaccination remains the most effective defense. One dose of the measles vaccine is about 93% effective, while two doses reach approximately 97% efficacy. Health officials warn that a recent decline in vaccination rates is largely responsible for the current outbreak.
