Polk County health officials report low MMR coverage, outline school exclusion rules amid measles watch

Crystal King, Polk County public health nurse, told the committee that the department's 40-day school immunization report shows locally low MMR coverage and described how the health department and schools coordinate when vaccine-preventable diseases appear.

King told the committee the county has 6,251 students enrolled; 5,420 (86.7%) meet the minimum state immunization requirements and 831 (13.3%) do not. The health department recorded 14 medical waivers, 77 religious waivers and 573 personal-conviction waivers (664 waivers total), plus 167 students who are behind schedule or without a waiver on file. King said the department supports schools by sharing state guidance, supplying vaccine clinics for eligible students and sending reminders to families who appear behind in the Wisconsin Immunization Registry (WIR).

King said Polk County's MMR (measles, mumps, rubella) rates for 2024 were 77.9% for 24-month-olds (one dose) and 78.6% for 5- to 18-year-olds (two doses). She contrasted those figures with statewide rates she quoted as 81.4% and 83.2%, and noted those levels are well under the 95% commonly cited as needed for herd immunity.

The department reviewed the state's school exclusion rules for a measles exposure. King summarized: if an unvaccinated student receives an MMR within 72 hours of exposure they may return to school and be monitored; students who do not receive vaccination after exposure may be excluded for 21 days from the onset date of the last identified case. She added that a single confirmed case is treated as an outbreak for exclusion purposes and that officials will restrict attendance by building or campus depending on facility layout.

On hospitalizations and other respiratory illnesses, public health staff reported that during the current respiratory season (October to the present) Polk County recorded 43 influenza hospitalizations, six RSV hospitalizations and 11 COVID-19 hospitalizations. For February alone staff reported 15 influenza hospitalizations, one COVID hospitalization and three RSV hospitalizations. Since November 2024 the county has recorded 18 pertussis (whooping cough) cases, predominantly in school-aged children.

Dr. Lagasse (identified in the meeting as 'Doctor') added clinical context about measles and airborne spread, emphasizing that measles virus can remain infectious in an exam room for hours and that exposure tracing and room sanitation must be handled carefully. He also noted that severe cases and neurologic injury can occur, particularly in young children.

Committee members asked whether schools receive school-level breakdowns. King said individual school-level aggregates are available because each school reports separately, but that the health department receives only counts (not student-identifying data) unless a FERPA-defined health emergency applies and the school provides additional information.

King noted practical steps the department is taking: flu clinics in schools, reminder campaigns using WIR pulls (the department selects Polk County residents by birth-date ranges and vaccine type), collaboration with the St. Croix Tribe, and RISE-3 grant-funded outreach. She said the department is preparing family-facing materials summarizing exclusion rules and next steps to distribute digitally to schools and as part of registration packets.

Direct quotes from meeting participants: "We have 6,251 students enrolled, and of those, 5,420 students or 86.7% are meeting the minimum state requirements," Crystal King said. On vaccination timelines, King said, "If they receive immunization within 72 hours of exposure, they may then return to school, but then they would be monitored for signs and symptoms." Dr. Lagasse warned that measles is highly infectious: "If a person with measles rash comes into an exam room, that examining room is basically contaminated for several hours," he said.

The department recommended parents who are unsure about adult immunity consult a clinician about titer testing or an additional MMR dose, and reminded pregnant patients to discuss RSV vaccination with their provider.

Why this matters: county immunization rates reported to the committee are below the thresholds public-health officials associate with herd immunity; the meeting record includes operational guidance (72-hour window, 21-day exclusion) that affects families, schools and employers during an exposure.

Committee next steps: King said she will provide digital handouts the schools can share and offered to supply school-level breakdowns to the committee upon request.

Ending: The committee thanked staff for the update and indicated public messaging (social media infographics, registration-packet inserts) would be pursued to make the exclusion and vaccination consequences clearer to parents and guardians.