Avian Influenza A Virus
Highly pathogenic avian influenza A (H5N1) virus infection reported in humans in the U.S.
The CDC (Centers for Disease Control and Prevention) confirmed that humans in the U.S. have tested positive for highly pathogenic avian influenza A (H5N1), also known as bird flu. The CDC says risk to the general public remains low. For more information on the current H5N1 bird flu situation, visit the CDC Avian Influenza H5 Bird Flu Current Situation Summary.
Wisconsin actively monitors for human cases of avian influenza and has plans in place to respond, if necessary. Currently, there is no imminent threat to Wisconsin since there is little evidence of sustained human-to-human spread of the bird flu in other parts of the world. It is difficult to predict if a bird flu virus will become a pandemic, but Wisconsin has plans in place to respond to that possibility, regardless of the source. You may also visit the Influenza (Flu) homepage for more information on how to protect yourself against the flu.
What is avian influenza?
Avian influenza occurs naturally among birds and is caused by influenza viruses. It can also spread to other animals. Animals carry the viruses in their intestines but usually do not get sick from them. However, avian influenza is very contagious among birds and other infected animals and can make some domesticated birds, including chickens, ducks and turkeys, very sick and can kill them.
PPE availability for farms and facilities
While farms and other facilities are encouraged to purchase and provide their own PPE, DHS is able to make some PPE available free of charge while supplies last. Eligible requesters include dairy farms, poultry farms, dairy processing plants, slaughterhouses (meat processing plants), or agencies supporting farm or slaughterhouse (meat processing) workers. Request free PPE.
Infected animals act as hosts to influenza viruses by carrying the virus in their intestines and shedding it in bodily fluids, such as saliva, nasal secretions and feces. Other animals become infected when they come in contact with these fluids.
Humans can become infected through contact with infected animals, animal products, or contaminated fluids. Avian flu can spread from birds to people and cause serious illness and even death.
Avian influenza has not mutated to a point where it could easily spread from person-to-person. It's difficult to predict if – or when – that might happen, or if it will result in an influenza pandemic.
People who have gotten sick with avian influenza have been in direct contact with infected animals.
Symptoms of avian influenza in humans range from typical influenza-like symptoms (fever, cough, sore throat, muscle aches) to eye infections, pneumonia, acute respiratory distress, viral pneumonia and other severe and life-threatening complications.
Health care providers will tell patients how to treat their illness, depending on the severity of their symptoms. Treatment may include hospitalization, supportive care and/or the use of antivirals.
Studies have shown that one antiviral drug called Tamiflu (oseltamivir) may possibly protect against the H5N1 strain of influenza.
Yes, it is safe to eat animal products that have been fully cooked. It is not safe to drink unpasteurized (raw) milk. General precautions should always be taken when handling any raw meat, including raw eggs, to avoid possibly spreading germs. These measures include:
- Washing hands and surfaces before and after food preparation.
- Avoiding using the same utensils on raw meat as on other foods, even cooked meat.
- Cooking raw meat thoroughly.
Note: The U.S. bans imports of animal products from areas where birds are infected with the H5N1 virus.
Wastewater monitoring for avian influenza
Wastewater (sewage) can be tested to detect traces of infectious diseases circulating in a community, which has become a valuable new tool for monitoring disease levels in communities. The amount of viral material found in the sewage can help determine how many people might be infected in a community, even if they don’t have symptoms, and can serve as an early warning sign for outbreaks or increasing levels.
The Wisconsin Wastewater Monitoring Program works with wastewater treatment plants across the state to regularly test samples for a variety of diseases including COVID-19 and the flu (influenza). In order to be vigilant for avian influenza, the program recently began testing samples for influenza A (H5), the virus that causes highly pathogenic avian influenza. Samples from selected sites (22 in Wisconsin) are tested twice weekly for this virus. Results are sent to CDC and are displayed on CDC’s National Wastewater Surveillance System Avian Influenza A (H5) dashboard (updated weekly on Fridays). The Wisconsin Wastewater Surveillance Program will make further announcements when plans are in place to display influenza A (H5) data on a state-run dashboard.
Wastewater data alone cannot determine the source of avian influenza A(H5) viruses. They could come from a human or from an animal (like a bird) or an animal product (like milk from an infected cow), and detections of avian influenza A(H5) virus in wastewater do not necessarily indicate human cases. DHS will work closely with the Department Agriculture, Trade, and Consumer Protection (DATCP), local health departments, and utilities after a detection to assist with investigating and responding to possible signs of bird flu in Wisconsin.
- CDC Travelers' Health website for important information before traveling.
- Wisconsin Department of Agriculture tracks the spread of avian flu in Wisconsin.
- USDA homepage for HPAI in Livestock, including a map of detections, requirements for farms, and guidance for worker safety.
- CDC – avian influenza
- U.S. government official website for information on pandemic flu and avian influenza
- Migrant Clinicians Network for information on Avian Flu on Dairy Farms: What Clinicians and Dairy Worker Patients Need to Know
- Department of Agriculture, Trade and Consumer Protection press release
- Resources for workers and employers is available on the DHS Farm Worker Health and Safety webpage
- What Employers Should Know About Highly Pathogenic Avian Influenza (HPAI), P-03308 Department of Health Services (DHS) fact sheet (multiple languages)
- What Workers Should Know About Highly Pathogenic Avian Influenza (HPAI), P-03308a DHS fact sheet (multiple languages)
Thomas Haupt, Influenza Surveillance Coordinator
Thomas.Haupt@dhs.wisconsin.gov
DHS Division of Public Health
Bureau of Communicable Diseases
Phone 608-266-5326
Fax 608-261-4976
Wisconsin Local Health Departments - Regional offices – Tribal agencies