Public health warns of measles exposures; Clay County monitoring two susceptible contacts

Clay County public health officials on Tuesday briefed the Board of Commissioners on an ongoing national measles outbreak, local vaccination coverage, and steps the county plans to take to expand vaccine access and monitor exposures.

Isaac Trebould, West Central District Epidemiologist with the Minnesota Department of Health, gave the update and described measles as "an acute systemic respiratory illness caused by a virus" that is highly contagious and can cause serious complications. He said measles transmits easily via airborne particles and noted a 90 percent attack rate in susceptible close contacts.

Trebuold summarized the recent national picture and regional clusters: more than 1,000 U.S. cases in 2025 at the time of his presentation, including an outbreak in Texas with several hundred cases and cases in neighboring North Dakota. He told the board that the Minnesota Department of Health was monitoring two susceptible people with local exposures and that public-health staff were following up to determine immunity and need for post-exposure action.

On vaccination coverage, Trebould reported that among Clay County children previously vaccinated before the pandemic, 91.4 percent had received at least one MMR dose by 24 months, compared with a Minnesota average of 89 percent. But for younger cohorts (children roughly 8 months to 1 year, 8 months behind schedule), Clay County’s 1-dose coverage fell to 67.3 percent versus a Minnesota average of 79.7 percent. Trebould warned those gaps increase the risk of local transmission if an exposure occurs.

He explained the timeline public health uses for exposures: about 10–12 days after exposure symptoms can begin; a rash typically starts 4–7 days after prodromal symptoms; and people are infectious from about four days before the rash until four days after. Trebould described options for post-exposure prophylaxis: "we can give vaccines to those, you know, exposures within 3 days, and that should prevent illness. Or we can give what's called immunoglobulin ... and that can be given within 6 days of the exposure." He noted the logistical challenge that public health is sometimes notified after the prophylaxis windows have closed.

Kathy (Clay County public health) said the county has ordered additional MMR vaccine through the Minnesota Vaccine for Children Program and will announce clinic appointments once doses arrive ("usually it takes about 7 to 10 days"). Cheryl (public-health clinic nurse) told the board that pharmacies provide MMR vaccine for people 19 and older but not for children, and reminded attendees that the county’s immunization registry (Minnesota Immunization Information Connection, MIIC) sends reminders and postcards when children are due for vaccines.

Commissioners asked about case identification timelines, school and childcare exclusion policies, and local clinic capacity. Trebould and county public-health staff said they were coordinating with regional health partners and school nurses; they noted that in other outbreaks local public health has at times excluded large numbers of unvaccinated students from schools for up to three weeks after exposure.

There was no board action required; the presentation was informational. County public health said it will publicize vaccine clinic appointments when additional MMR doses arrive and will continue case monitoring and contact follow up for the two locally monitored exposures.