DELAWARE HEALTH ADVISORY #526: BACKYARD POULTRY FLOCK TESTS PRESUMPTIVE POSITIVE FOR AVIAN INFLUENZA

The Delaware Division of Public Health (DPH) is sending this health advisory to alert clinicians and health care partners about human exposure to a mixed species poultry flock with H5 avian influenza.

Summary
DPH is sending this health advisory to alert clinicians and health care partners that a backyard poultry flock tested presumptive positive for H5 highly pathogenic avian influenza (HPAI A(H5N1)) in Kent County. DPH has identified and contacted all known individuals with potential exposure to the affected flock. DPH is recommending that clinicians and health care providers should consider the possibility of avian influenza infection in persons showing signs or symptoms of acute respiratory illness or conjunctivitis who have relevant exposure history including but not limited to contact with potentially infected sick or dead birds, consumption of unpasteurized milk, or direct contact with water or surfaces contaminated with infected feces.

Background
Highly pathogenic avian influenza (HPAI) A(H5N1) virus primarily affects birds and is highly contagious among avian species. Since March 2024, the Centers for Disease Control and Prevention (CDC) has reported detections of HPAI A(H5N1) in dairy cattle, poultry, and several other animal species across the United States. In 2025, the CDC has confirmed 70 human cases of HPAI infection, the majority occurring among farm workers with known exposure to infected animals. A small number of cases, however, have been reported without any known contact with infected poultry or livestock.

Reported symptoms in infected individuals include fever, cough, sore throat, runny or stuffy nose, muscle or body aches, headache, fatigue, conjunctivitis, and, in some cases, shortness of breath or difficulty breathing. At this time, human-to-human transmission of HPAI A(H5N1) remains highly unlikely, and there have been no confirmed cases of person-to-person spread.

On November 7, 2025, the Delaware Department of Agriculture announced an HPAI detection among a mixed species poultry flock in Kent County. DPH has identified and contacted all known individuals with potential exposure to the affected flock.

Reporting
Delaware physicians, laboratories, and other health care providers are required by regulation to report patients with influenza A to the Office of Infectious Disease Epidemiology (OIDE). Reporting enables appropriate public health follow-up for patients, helps identify outbreaks, and provides a better understanding of disease trends in Delaware. Cases can be reported to DPH OIDE by calling 302-744-4990 (normal business hours) or 1-888-295-5156 (outside of normal business hours). You may also complete a Notifiable Disease Report PDF Form and fax the form to DPH at 302-622-4149 or email reportdisease@delaware.gov. The form can be found online at https://dhss.delaware.gov/wp-content/uploads/sites/12/dph/pdf/morbiditycardfillable.pdf.

In addition, if health care providers suspect individuals who have received a positive influenza A test result and possible exposure to poultry, birds, or dairy cattle, they should call OIDE immediately at 302-744-4990 (normal business hours) or 1-888-295-5156 (outside of normal business hours)) and send the samples to the Delaware Public Health Laboratory (DPHL) for Influenza A subtyping.

Recommendations
Clinicians should consider the possibility of HPAI A(H5N1) virus infection in people showing signs or symptoms of acute respiratory illness or conjunctivitis and/or who have relevant exposure history. 

Examples of symptoms include but are not limited to: 
• Mild illness: cough, sore throat, eye redness or eye discharge such as conjunctivitis, fever or feeling feverish, rhinorrhea, fatigue, myalgia, arthralgia, and headache.

• Moderate to severe illness: shortness of breath or difficulty breathing, altered mental status, and seizures.

• Complications: pneumonia, respiratory failure, acute respiratory distress syndrome, multi-organ failure (respiratory and kidney failure), sepsis, and meningoencephalitis.

If signs and symptoms compatible with avian influenza A(H5N1) virus infection are present: 
• Encourage patients who do not need urgent medical care to isolate at home, away from their household members and not go to work or school until it is determined they do not have avian influenza A(H5N1) virus infection.

• For patients seeking health care, isolate patients and follow infection control recommendations, including using proper personal protective equipment.

• Initiate empiric antiviral treatment as soon as possible. Do not delay treatment while awaiting laboratory results.

• Notify OIDE to arrange testing for influenza A(H5N1) virus at 302-744-4990 (normal business hours) or 1-888-295-5156 (outside of normal business hours).

• Collect respiratory specimens from the patient to test for influenza A(H5N1) virus at DPHL. If the exposed person has conjunctivitis, with or without respiratory symptoms, both a conjunctival swab and a nasopharyngeal swab should be collected for testing.

• DPH strongly recommends seasonal influenza vaccinations to reduce the prevalence and severity of seasonal influenza as well as its impact during this period of heightened concern for avian influenza.