Outbreaks, Recalls, and Investigations in Wisconsin
Below is a list of selected outbreaks, recalls, and investigations with wide impact in Wisconsin.
The Wisconsin Department of Health Services (DHS), along with the Wisconsin Department of Agriculture, Trade, and Consumer Protection (DATCP), local health departments, and federal partners, are working to investigate a confirmed human case of High Pathogenic Avian Influenza A or HPAI A(H5N1), also known as bird flu.
- On December 12, 2024, DATCP confirmed a case of High Pathogenic Avian Influenza A or HPAI A(H5N1) in a commercial poultry flock in Barron
County , Wisconsin. - On December 18, 2024, DHS received report of a presumptive positive case of HPAI A(H5N1) in a farm worker of Barron County, Wisconsin. DHS is actively coordinating with Barron County Health and Human Services, Wisconsin State Laboratory of Hygiene (WSLH), and DATCP to identify and monitor those who may have been exposed.
- On December 20, 2024, DHS received test results from the CDC (Centers for Disease Control and Prevention) on specimens collected from the presumptive positive human case of HPAI A(H5). Results of the test confirm HPAI A(H5), and the case will now be reported to the CDC as a confirmed human case of HPAI A(H5).
- According to the CDC, the current HPAI A(H5N1) situation continues to pose a low risk to general community members. HPAI viruses do not pose a food safety risk. Properly cooking meat and eggs to the recommended internal temperature of 165˚F kills HPAI viruses, as does pasteurizing milk.
About HPAI A(H5N1) in animals
Wild birds, especially waterfowl, can become infected with HPAI and may show no signs of infection. When the wild birds migrate, they have the potential to spread HPAI to other birds and animals. To prevent the spread of HPAI and other diseases to people and domestic animals, Wisconsinites and their pets should avoid touching sick or injured wild birds or mammals. It is important to avoid any wild animal that is behaving abnormally. Abnormal behavior includes:
- Pacing or walking in circles,
- Unbalanced posture, or
- Head and body tremors.
DATCP continues to urge all livestock owners to implement strong biosecurity measures to protect their flocks and herds from the disease. This includes:
- Washing hands
- Disinfecting equipment
- Restricting access to animals
- Separating new additions to the flock or herd for at least 30 days.
Poultry owners are asked, when possible, to keep their birds indoors.
To report increased mortality or signs of illness among domestic birds, dairy cattle, or other animals, contact DATCP at 608- 224-4872 during business hours or 800-943-0003 after hours and weekends.
For updates on how the virus is affecting domestic birds in Wisconsin, and to find resources on protecting Wisconsin poultry, visit DATCP’s HPAI in
About HPAI in people
HPAI viruses are a form of influenza that primarily affects birds. In rare circumstances, HPAI viruses can infect humans when prolonged close contact with infected birds or other animals occurs. No widespread person-to-person transmission of HPAI viruses has occurred. The sporadic HPAI cases that have occurred have ranged in severity from no symptoms to mild illness to severe disease that resulted in death.
Recommendations to the public
Viruses that spread from animals to
- Everyone 6 months and older should get the flu vaccine every year to protect themselves against seasonal flu.
- As a general precaution, people should avoid close contact with sick animals. People who have had contact with infected or sick
animals should monitor for flu-like symptoms, seek medical care if they feel sick, and tell their health care provider that they had contact with infected animals. - Anyone involved in poultry or livestock production, even those with small operations, should evaluate their biosecurity
measures to assure the health of their animals and their workers. - Whenever possible, people should avoid direct contact with wild birds and other wildlife and observe them only from a distance. People should also avoid touching any wild animals showing signs of
HPAI and not touch dead birds or wildlife with their bare hands. If touching dead animals is necessary, wear gloves or use a plastic bag to put it in the garbage. People should wash their hands with soap and water and throw away any gloves after disposing of dead birds or wildlife. Contact theDNR to report any sick or dead wildlife.
Additional resources
The Wisconsin Department of Health Services (DHS) is reporting a significant increase in cases of pertussis, also known as whooping cough, across Wisconsin. Data in the state, and nationally, shows that cases are now similar to pre-pandemic levels. To prevent the spread and protect against severe symptoms or hospitalization, DHS urges Wisconsinites to make sure they and their children are up to date on their pertussis vaccine, and to take other steps to stay healthy.
As of January 10, 2025, DHS has received reports of 2,527 confirmed cases of pertussis. Seventy-one counties have had at least one case since January 1, 2024. While the age of people diagnosed with pertussis ranges from 1 month to 90 years, approximately half (49%) of the cases are in individuals aged 11 to 18 years. One hundred infants have been identified with pertussis and 14 have been hospitalized. No deaths have been reported.
What are the symptoms of pertussis?
At first, a person with whooping cough may seem like they have a cold. Early symptoms include:
- Low‐grade fever.
- Slight cough.
After about a week, the cough gets worse. The cough causes other symptoms, such as:
- Difficulty breathing.
- Needing to take a deep breath that makes a “whoop” sound.
- Vomiting.
Babies may not have a cough. Instead, they may stop breathing for several seconds, called apnea. Or they may look like they are gasping for air. Babies are at greatest risk for getting pertussis and then having serious complications from it, including death. That’s why it’s important that pregnant people and everyone around the baby are up to date with their pertussis vaccines.
What to do if you think you have pertussis
It is very important to treat whooping cough early. If you or someone you know experiences symptoms of pertussis, stay home and call your health care provider and follow their instructions. Severe symptoms, such as difficulty breathing, need immediate medical care.
How to stay protected against pertussis
The best way to prevent pertussis, or reduce the severity of symptoms, is to stay up to date on the recommended pertussis vaccination. People of all ages need the pertussis vaccine. The CDC (Centers for Disease Control and Prevention) recommends different vaccines against pertussis for different age groups.
- Children should receive five doses of the DTap vaccine from age 2 months to 6 years.
- Adolescents from 11–12 years old should receive one dose of Tdap vaccine.
- Adults who have never had a pertussis vaccine should receive one dose of the Tdap vaccine.
- Pregnant people should receive Tdap between 27 to 36 weeks during each pregnancy to protect the newborn before they are old enough to get the DTap vaccine.
Wisconsin residents can find their immunization records using the Wisconsin Immunization Registry
For Wisconsin residents who do not have health insurance, or whose insurance may not cover vaccines, the Vaccines for Children and Vaccines for Adults programs may be able to help.
Taking the following daily actions can also help stop the spread of germs:
- Wash your hands often with soap and water for 20 seconds.
- Avoid touching your nose, eyes, and mouth.
- Stay home and away from others if you feel sick.
- Avoid being around others who are sick.
- Cover your nose and mouth when you cough or sneeze and encourage children to do the same.
Visit the DHS Pertussis webpage for more information.
To view previous outbreaks and investigations, visit our Past Outbreaks in Wisconsin page.