Outbreaks in Wisconsin
Below is a list of selected outbreaks, recalls, and investigations with wide impact in Wisconsin.
The Wisconsin Department of Health Service (DHS) is working with state and federal partners to investigate a multistate outbreak of Listeria monocytogenes infections linked to a yet unknown food source.
- According to the CDC (Centers for Disease Control and Prevention), 18 people in 15 states have been infected with the outbreak strain of Listeria. Seventeen people have been hospitalized and zero deaths have been reported.
- Wisconsin has two laboratory-confirmed cases and zero deaths linked to this outbreak.
Recall information: None currently.
Advice to consumers
DHS and CDC urge people to take the following steps:
- Call a healthcare provider if you have symptoms of Listeria.
- Pregnant people usually experience only fever, fatigue, and muscle aches. However, Listeria can cause pregnancy loss or premature birth. It can also cause serious illness or death in newborns.
- People who are not pregnant may experience headache, stiff neck, confusion, loss of balance, and convulsions, in addition to fever and muscle aches.
- Provide information to help identify the source of the outbreak.
- If you are diagnosed with Listeria, someone from your local or tribal health department or DHS may contact you to find out what you ate in the month before you became sick. You may also be asked for copies of receipts, shopper card numbers, or leftover food for testing.
- Share the latest outbreak information with your friends and family who are at higher risk of getting sick from Listeria (aged 65 and older, are pregnant, or have a weakened immune system)
See the Food and Drug Administration (FDA) and CDC for more information on this investigation, and to stay up to date on other food-borne outbreaks and recalls.
Since May 14, 2022, the CDC (Centers for Disease Control and Prevention) has been monitoring new clusters of mpox in non-endemic countries throughout Europe, North America, and Australia. On June 30, 2022, the Wisconsin Department of Health Services (DHS) identified the first case of confirmed orthopoxvirus, presumed to be mpox, associated with this outbreak in a Wisconsin resident. DHS is working with the CDC and other state and local partners to enact measures to prevent the spread of mpox.
For more information on this outbreak, visit our Mpox Data webpage.
The risk of widespread transmission of mpox to the public is relatively low. People most at risk for mpox include:
- People who had close physical contact with a person who has mpox (such as household members or intimate partners).
- People who had close physical contact with a person who had a rash that looks like mpox.
- People who attended events or venues where mpox transmission has occurred.
- Gay, bisexual, or other men who have sex with men who had multiple sexual partners in the past 14 days.
DHS and CDC urge all Wisconsinites to take the following steps:
- Know the symptoms and risk factors of mpox.
- Avoid skin-to-skin contact with individuals who are showing a rash or skin sores. Don’t touch the rash or scabs, and don’t kiss, hug, cuddle, have sex, or share items, such as eating utensils or bedding with someone with mpox.
- In areas where mpox is spreading, participating in activities with close, personal, skin-to-skin contact may pose a higher risk of exposure.
- If you were recently exposed to the virus, contact a doctor or nurse to talk about whether you need a vaccine to prevent disease. Monitor your health for fever, chills, swollen lymph nodes and new, unexplained rashes and contact a health care provider if one occurs. If you become ill, avoid contact with others until you receive health care.
- If you are sick with mpox, isolate at home until the rash has fully resolved, the scabs have fallen off, and a fresh layer of skin has formed.
- CDC HAN: Mpox Virus Infection in the United States and Other Non-endemic Countries
- CDC U.S. Mpox
- World Health Organization: Mpox
- Wisconsin DHS Health Alert #44: Mpox: Recommendations for Detection and Reporting
- Wisconsin DHS Health Alert #46: Mpox Detected in Wisconsin Resident
Wisconsin DHS Health Alert #47: Expanded Mpox Testing Capacity
The U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspective Service (APHIS) continues to detect highly pathogenic avian influenza (HPAI) A (H5N1) in U.S wild birds and commercial poultry farms (domestic birds). HPAI is a serious disease that is highly contagious and often fatal to domestic birds including chickens, ducks, and turkeys. It can be spread by contact with infected birds or the premise where the birds are housed, equipment used on the premise with infected birds, and clothing worn by people working with poultry. HPAI can spread from birds to people and cause serious illness and even death. People who have gotten sick with HPAI have been in direct contact with infected birds or their premise.
As of September 15, 2022, 43 states have confirmed cases of HPAI in wild birds and 39 states have detected HPAI in poultry farms as a result of this outbreak. The most recent case in Wisconsin was detected on August 31, 2022, in a backyard flock in Washington County. This is the first case of HPAI detected in Wisconsin in domestic poultry since May 2022. Federal, state, and local agencies are working together to help stop the spread of HPAI by quarantining affected premises.
As of September 20, 2022, only one case of human infection with the current H5N1 virus has been detected in the United States. The case occurred in Colorado in a person who had direct exposure to poultry and was involved in the depopulation of poultry with presumptive H5N1 avian influenza. According to the Centers for Disease Control and Prevention (CDC), the current HPAI outbreak continues to pose a low risk to general community members. HPAI viruses also do not pose a food safety risk. Properly cooking poultry and eggs to the recommended internal temperature of 165˚F kills HPAI viruses.
Wild birds 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. On May 13, 2022, The Wisconsin Department of Natural Resources (DNR) confirmed that wild red fox kits in Wisconsin tested positive for a strain of HPAI. Additional cases have also been confirmed in other wild mammals including bobcats, skunks, bears, and seals. 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.
If you or your pet had direct or close contact with a sick or wild animal, contact your local public health department or health care provider (or your pet’s veterinarian). Even with the detection HPAI in Wisconsin mammals, DHS and the CDC still consider the human risk assessment for the public as low.
About HPAI in people
HPAI viruses are a form of avian influenza that primarily affects birds. In rare circumstances, HPAI viruses can infect humans when prolonged close contact with infected birds occurs. No widespread person-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 for the public
Viruses that spread from animals to people have the potential to mutate or combine with human influenza viruses to become more infectious variants. This is why public health measures to prevent the spread of HPAI to people are so important.
- 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 wild and domestic birds (poultry). People who have had contact with infected or sick birds 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 birds.
- Anyone involved in poultry production, even those with small backyard flocks, should evaluate their biosecurity measures to assure the health of their flock.
- Whenever possible, people should avoid direct contact with wild birds and observe them only from a distance. People should also avoid touching any wild birds showing signs of HPAI and not touch dead birds or wildlife with their bare hands. If touching a dead bird 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 the DNR to report any sick or dead wildlife.
- Avian Influenza A (H5N1) Virus | Wisconsin Department of Health Services
- Department of Agriculture, Trade and Consumer Protection (DATCP) Home Avian Influenza (wi.gov)
- Information on Bird Flu | Avian Influenza (Flu) (cdc.gov)
- Bird Flu Current Situation Summary | Avian Influenza (Flu) (cdc.gov)
- Highly Pathogenic Asian Avian Influenza A(H5N1) Virus | Avian Influenza (Flu) (cdc.gov)
- March 7, 2022 Update: H5N1 Bird Flu Poses Low Risk to the Public | Avian Influenza (Flu) (cdc.gov)
- USDA APHIS | 2022 Detections of Highly Pathogenic Avian Influenza
The Wisconsin Department of Health Services (DHS) is working with the Department of Agriculture, Trade and Consumer Protection (DATCP), and local health departments to investigate cases of Salmonella associated with shelled peas produced by Green Barn Farm Market. The shelled (loose) peas were sold at Green Barn Farm Market farm stands and farmers markets in Ripon, Green Bay, Madison, and Fond du Lac, and Green Valley Acres Farm farm stands in Neenah.
- As of July 29, 2022, six people have been infected with the same strain of Salmonella.
- To date, three of the six patients identified have required hospitalization.
Anyone who bought shelled (loose) peas from Green Barn Farm Market or Green Valley Acres Farm since July 1, 2022, is advised not to eat them and to throw them away, even if they are frozen. People who consumed the peas who are experiencing signs or symptoms of salmonellosis are encouraged to contact a doctor right away to let them know they may have been exposed to Salmonella. Signs and symptoms of salmonellosis include:
- Abdominal pain,
- Fever, and
- Vomiting that lasts for several days.
At this time, DHS and local health departments are re-interviewing case-patients to gather information about their farmers market exposures. DATCP is working with the vendor to identify the source of contamination on the farm.
- DHS Salmonellosis Fact Sheet, P-42088 (Multiple Languages): A fact sheet with general information on salmonellosis, including symptoms, treatment, and prevention.
- Salmonella Information for Health Professionals: The CDC webpage covering clinical features of a Salmonella infection, diagnosis, treatment, and more.
- For free, confidential support finding a doctor or other health care provider near you, dial 211 or 877-947-2211, or text your ZIP code to 898-211. Find resources online at 211Wisconsin.org.
The Wisconsin Department of Health Services (DHS) is working with local, state, and federal partners to investigate multiple outbreaks of Salmonella infections linked to contact with live backyard poultry.
- As of September 22, 2022, the Centers for Disease Control and Prevention (CDC) reports that 1,191 people, in all 50 states, the District of Columbia, and Puerto Rico have been infected with one of the outbreak strains of Salmonella.
- Illnesses linked to these outbreaks started on February 3, 2022.
- To date, 211 hospitalizations have been reported nationally, as well as two deaths.
- Children younger than 5 years have accounted for 21% of the illnesses nationally.
- In Wisconsin since March 2022, 49 people have been infected with one of the outbreak strains of Salmonella.
- Among Wisconsinites with infections linked to the national outbreak:
- Case patients reside in 38 counties across the state.
- Seven infections have resulted in hospitalization. No deaths have been reported.
- Infections occurred in people ranging from under 1 to 71 years of age, with an average age of 36 years. Children less than 5 years of age have accounted for less than 10% of infections.
Salmonella and backyard poultry
Outbreaks of Salmonella infections linked to contact with backyard poultry occur every year in the U.S., including in Wisconsin residents. Many of these infections are preventable.
- Poultry, including healthy and clean backyard poultry, can have Salmonella germs in their poop and on their bodies (feathers, feet, and beaks). The germs can easily spread to their cages, coops, eggs, and equipment used to care for them. People can get sick from Salmonella if they touch the birds or anything in their environment and then touch their mouth or food before washing their hands.
- Children younger than 5 years are more likely to get sick with Salmonella because their immune systems are still developing. They also are more likely to put their fingers or other items with germs into their mouths.
Reduce your risk
People who own or have contact with poultry can take these steps to reduce the risk of becoming ill with salmonellosis:
- Always wash your hands after touching backyard poultry, their eggs, or anything within the areas in which they live or roam.
- Don’t kiss or snuggle backyard poultry, and don’t eat or drink around them.
- Supervise kids around flocks and don’t let children younger than 5 years touch chicks, ducklings, or other backyard poultry.
- Handle eggs safely.
- Call your health care provider right away if you have any of these severe symptoms:
- Diarrhea and a fever higher than 102°F
- Diarrhea for more than three days that is not improving
- Bloody stools
- Prolonged vomiting that prevents you from keeping liquids down
- Signs of dehydration, such as:
- Making very little urine
- Dry mouth and throat
- Dizziness when standing up
For more information about how to reduce your risk of getting sick:
- Please see our Backyard Poultry flyer, P-01788, (PDF) for more information about how to prevent these infections.
- Please view CDC’s video Got a backyard flock? Here’s how to prevent Salmonella.
- Information about backyard poultry can also be found at the DHS backyard poultry webpage.
See the CDC webpage for more information on this investigation, and to stay up to date on other foodborne outbreaks and recalls: CDC: Salmonella Outbreaks Linked to Backyard Poultry
The CDC (Centers for Disease Control and Prevention) is working with state and local health departments to identify children with hepatitis (inflammation of the liver) of unknown cause. From November 2021 to February 2022, health care providers at a large children’s hospital in Alabama identified nine children experiencing significant liver injury, including three with acute liver failure. All nine children tested positive for adenovirus and those subtyped identified Adenovirus 41. All nine children were previously healthy and had no risk factors for hepatitis. The children were from different parts of the state and had no known contact with each other or common exposures prior to infection.
Since being notified of the cluster of cases in Alabama by the CDC, the Wisconsin Department of Health Services (DHS) is now investigating several past cases of hepatitis of unknown cause in Wisconsin children. Cases of hepatitis in children without known cause have also been detected in other parts of the United States and throughout the United Kingdom and Europe. According to a CDC update on May 6, 2022, at least 109 children in 25 states have been identified in the Unites States as part of the cluster of cases. Overall, at least 228 probable cases in 20 countries have been identified, according to the World Health Organization
As of May 12, 2022, the cause of this cluster of hepatitis cases is still unknown. However, it is important to note the virus that causes COVID-19 and the COVID-19 vaccines have been ruled out as possible causes. The median age of children with hepatitis of unknown cause in the U.S. is two years and children under five years are not yet eligible for COVID-19 vaccination. It is also unclear whether the number of children being diagnosed with hepatitis is increasing or if these cases can be attributed to improvements in hepatitis surveillance.
Hepatitis is inflammation of the liver that can be caused by viral infections, alcohol use, toxins, medications, and certain other medical conditions. The most common causes of viral hepatitis in the United States, the hepatitis A, hepatitis B, and hepatitis C viruses, have all been ruled out as a likely cause. Signs and symptoms of hepatitis include:
- Loss of appetite
- Abdominal pain
- Dark Urine
- Light-colored stools
- Join pain
About Adenovirus 41
Adenovirus type 41 is a common cause of diarrhea, vomiting, and fever in children. In some cases, it can also cause respiratory symptoms. There have been reports of hepatitis in children with weakened immune systems who have been infected with adenovirus type 41. However, adenovirus type 41 is not known to cause hepatitis in healthy children. While adenovirus type 41 has been detected in some children with unknown hepatitis, it has not been determined to be the cause of this cluster of cases at this time.
Contact your child’s health care provider if you have questions about your child’s health. DHS recommends parents with children who are concerned about hepatitis to:
- Be aware of symptoms of liver inflammation
- Keep children up to date on all recommended vaccinations
- Take everyday steps to keep your child healthy:
- Encourage hand washing
- Avoid sick people
- Cover coughs and sneezes, and
- Avoid touching the eyes, nose, or mouth.
- Overview: Children with Hepatitis of Unknown Cause | CDC
- HAN Archive - 00465 | Health Alert Network (HAN) (cdc.gov)
- Wisconsin DHS Health Alert #42: Recommendations for Adenovirus Testing and Reporting of Children with Acute Hepatitis of Unknown Etiology (govdelivery.com)
- Viral Hepatitis Infection | Wisconsin Department of Health Services
- Adenovirus | Wisconsin Department of Health Services
- Multi-Country – Acute, severe hepatitis of unknown origin in children (who.int)
The Wisconsin Department of Health Services (DHS) and the Monroe County Health Department are working with federal partners at Fort McCoy to investigate an outbreak of measles among people who recently traveled from Afghanistan during the United States government’s emergency evacuation efforts. To date, all cases have been identified among people currently based at Fort McCoy. At the time of this update, there is no evidence of community spread in Wisconsin beyond Fort McCoy.
- As of October 14, 2021, a total of 22 cases of measles has been confirmed.
- People diagnosed with measles at Fort McCoy have ranged in age from 4 months to 26 years old and 14 (64%) have required treatment at area hospitals.
- This information will be updated every Thursday at 2 p.m.
Most Wisconsinites are vaccinated against measles as children, which provides lifetime immunity. The risk of measles transmission in the surrounding communities is considered to be low at this time. However, people who have never been vaccinated and are exposed to a person with measles can spread the virus to others in the community, leading to outbreaks. The best way to prevent measles is to get vaccinated with the Measles, Mumps, Rubella (MMR) vaccine. Two doses of MMR vaccine are about 97% effective at preventing measles; one dose is about 93% effective. Wisconsin residents can check their vaccination status in the Wisconsin Immunization Registry (WIR).
Local health departments can provide MMR vaccine to uninsured adults through the Vaccines for Adults program, based on vaccine ability and capacity. The Wisconsin Vaccines for Children Program covers the cost of vaccines for eligible children.
In order to prevent further spread to Fort McCoy and surrounding communities, federal agencies coordinating the response offered vaccination against measles and other communicable disease to all Afghan evacuees in mid-September. Staff or visitors who have been to Fort McCoy and had contact with evacuees or the living areas of evacuees may be at increased risk for measles. DHS and the Monroe County Health Department are working closely with federal partners on base to offer vaccination to these higher risk groups in order to prevent spread.
Measles is a highly contagious, serious disease caused by a virus. The virus can be spread through the air and through direct contact with persons who are infected. Unvaccinated young children and other non-immune adults are at highest risk of serious disease from measles. Symptoms of measles generally start 10-12 days after exposure to the virus and include:
- Runny nose
- High fever (may be greater than 104 F)
- Red, watery eyes, or conjunctivitis (“pink eye”)
- A red rash with raised bumps that starts at the hairline and moves to the arms and legs three to five days after symptoms begin
For a full description of measles, see the DHS measles fact sheet and the CDC measles webpage.
In general, people born before 1957 are considered immune. All other adults without laboratory evidence of immunity should have at least one dose of measles-containing vaccine, and children should have two doses. See the DHS measles webpage for more information about measles and recommended vaccination schedules.
Wisconsin Investigation Details
We plan to update our data daily by 2 p.m.
We are closely monitoring COVID-19 with officials at local, state, and federal levels.
COVID-19 continues to be very contagious. We should continue to limit our interactions with others as much as possible to protect ourselves, our communities, and the capacity of our health care system.
- Get vaccinated against COVID-19.
- Practice physical distancing of 6 feet.
- Wear a mask.
- Wash your hands frequently, and avoid touching your face.
- If you have symptoms or have been exposed to COVID-19, get tested.
- Contact your doctor and ask to be tested.
- Complete an online health screening assessment, and a licensed health practitioner will contact you.
- See if a community testing site is available near you.
You are not alone. We are in this together. Do not hesitate to ask for help.
Latest news from Gov. Evers:
Media briefings, scheduled as needed:
- Upcoming briefings will be announced on Facebook.
- Watch past media briefings.
COVID-19: Wisconsin data
Wisconsin Case Counts
As of January 11, 2021
More information about the e-cigarette or vaping associated lung injury can be found on the Vaping and Lung Injury Investigation webpage.
Media requests should go to the DHS media or 608-266-1683.
|Case Status||Number of Cases|
|Confirmed and Probable Cases*||119|
*Reporting the number of confirmed and probable cases of EVALI in Wisconsin during July 2019-current date.
To view previous outbreaks and investigations, please visit our Past Outbreaks in Wisconsin page.