Wisconsin Vaccine Preventable Disease Updates: January 2025

Wisconsin Department of Health Services sent this bulletin at 01/09/2025 10:00 AM CST
Wisconsin Department of Health Services

Immunization Program
WI VPD updates light

This message is being sent to Tribal health directors, local health officers, local health department staff, local health department nurses, Vaccines for Children providers, Vaccines for Adults providers, and key DHS staff.

January 2025

Wisconsin Vaccine Preventable Updates provides statewide data on select vaccine preventable diseases from the previous month. 

Pertussis

As of December 31, 2024, Wisconsin has 2,419 confirmed cases statewide. Seventy-one counties have had at least one case since January 1, 2024. While cases range in age from 1 month to 90 years, about half (49%) of the cases are in adolescents aged 11–18 years. Ninety-seven infants have been identified with pertussis and 13 have been hospitalized. No deaths have been reported.

The most recent weekly pertussis case count data can be found on the DHS website. Please note the data are preliminary and subject to change.

Pertussis resources 

The Communicable Disease Case Reporting and Investigation Protocol: Pertussis  has been updated. It contains up-to-date information on laboratory testing, clinical presentation, and treatment for Pertussis. 

The educational flier Seasonal Influenza (Flu): Is it the Flu, a Cold, or Whooping Cough? | Wisconsin Department of Health Services is a valuable source of information as influenza begins to circulate. 

Varicella

As of December 31, 2024, Wisconsin has 212 confirmed and probable cases statewide. Fifty-five counties have had at least one case since January 1, 2024. About half (51%) of the cases had a positive laboratory test. While cases range in age from 3 weeks to 61 years, the median age of the cases is 9 years. Five individuals have been hospitalized.

The majority of cases continue to occur among unvaccinated individuals where about three-quarters (71%) of cases were not vaccinated or had an unknown vaccine history. No deaths have been reported.

Varicella resources

DHS chickenpox webpage

CDC chickenpox webpage

CDC laboratory testing information 

Measles: No additional cases in Wisconsin

Wisconsin had one case of Measles in early 2024 and has had no secondary or new cases as of December 31, 2024.

Wisconsin vaccination rate data

The immunization program has vaccination rate dashboards for influenza, COVID-19, and RSV. These dashboards display vaccination data by location, age group, and demographics. The influenza dashboard also highlights how the CDC’s Social Vulnerability Index (SVI) aligns with influenza vaccination coverage.