Lewis and Clark County has confirmed a positive case of measles, the first in several decades, according to a Monday press release from public health officials.
According to the press release, the infected individual is a minor who had received one dose of the MMR vaccine. The release noted that the parents reported the person’s vaccine status, but it has not yet been confirmed by health records.
Health officials said that no local day cares or summer youth programs are connected to the case and that the individual’s last “infectious day” was Aug. 12. The individual was not in the county for most of their contagious period, public health officials reported.
“The great news for us, in the Helena area, is that most of our population is fully immunized against measles,” LCPH nurse Angelique Turner said in the release. “So all that said, while we must stay informed and prepared, there is no reason for panic.”
One person in the infected individual’s household is not immunized and is quarantined at home, with no reported symptoms.
LCPH is working with other affected jurisdictions on contact tracing, though officials did not clarify which locations that work included.
Health officials continue to ask county residents to check their measles vaccination records and get vaccinated if they are not or can’t find proof of being vaccinated. Residents can request the status of their immunizations on the Lewis and Clark Public Health website. The public can also find updated reports of measles public exposure locations through an online LCPH Data Portal.
LCPH officials encouraged the public to contact their primary health care providers if they have further questions or concerns about measles exposure.
There have been 30 measles cases in Montana since the start of the most recent outbreaks, according to the state health department. Two of those cases have resulted in hospitalizations. The state has recorded no deaths caused by measles in the recent outbreaks.
According to the most recent information available from the Centers for Disease Control and Prevention, as of Aug. 5, the country had confirmed a total of 1,356 measles cases in 41 states. In 2020 the United States declared measles eliminated, but low vaccination rates have led to recent outbreaks.
A person who has been exposed to measles can spread the virus four days before they develop a rash — one of the first physical signs of infection — and can remain contagious for several weeks. Symptoms may not appear for up to 21 days after exposure, giving a person’s transmissibility a long tail.
Health experts in Montana and elsewhere in the U.S. have stressed that the best protection against the measles virus for adults and children is the MMR vaccine, a long-lasting immunization that is typically recommended for infants between 12 and 15 months of age. In some circumstances of community transmission, health officials in Montana have recommended an earlier vaccination schedule for young infants.
Montana is the only state in the nation that does not publicly share data about county-by-county vaccination levels, particularly among young children who are most at risk for adverse effects from measles. An existing data collection program was scrapped after the state legislators passed a law striking that language from code in 2021.
A recent federal survey of 127 Montana children born in 2021 put the state’s estimated measles vaccination rate among toddlers at 85.5%, one of the lowest figures in the country.
Reporter Mara Silvers contributed to this story.
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