Current Situation in US
Highly Pathogenic Avian Influenza (HPAI) A(H5N1) is widespread in wild birds worldwide and is causing outbreaks in poultry and US dairy cows with several cases in US dairy workers. While the current public health risk is low, CDC is watching the situation carefully and working with states to monitor people with animal exposures.
- People: 67 cases | 1 death associated with H5N1 bird flu infection in the United States
- Person-to-person spread: None
- Current public health risk: Low
- Dairy Cows: Ongoing multi-state outbreak
- Wild Birds: Widespread
- Poultry Flocks: Sporadic outbreaks
- Mammals: Sporadic infections
Pediatric Information
On November 22, 2024, the CDC confirmed a human infection with HPAI H5N1 in a child in California. This is the first reported avian influenza H5 virus infection in a child in the United States. Consistent with previously identified human cases in the United States, the child reportedly experienced mild symptoms and received flu antivirals. The child is recovering from their illness. An investigation by the California Department of Public Health (CDPH) into the child's possible H5N1 exposure source is ongoing. Contact tracing continues, but there is currently no evidence of person-to-person spread of H5N1 bird flu from this child to others. To date, there has been no person-to-person spread identified associated with any of the H5N1 bird flu cases reported in the United States. However, children, particularly those with exposure to dairy cows, raw milk, poultry flocks, or wild birds, may be at risk of HPAI H5N1 infection.
The commercial milk and formula supply is considered safe. In late April 2024, the US Food and Drug Administration reported that HPAI viral fragments were found in 1 of 5 retail milk samples tested by polymerase chain reaction testing. Additional testing did not detect any live, infectious virus, indicating the effectiveness of pasteurization at inactivating the virus. Limited sampling of retail powdered infant formula and powdered milk products marketed as toddler formula revealed no viral fragments or viable virus.
AAP News | December 18, 2024: First severe case of bird flu in U.S. confirmed by CDC
AAP Policy Statement: Consumption of Raw or Unpasteurized Milk and Milk Products by Pregnant Women and Children
CDC: Raw Milk and HPAI: Advice for Healthcare Providers
Additional Information on US Cases
- 2022 Case: https://www.cdc.gov/media/releases/2022/s0428-avian-flu.html
- 2024 Case 1: Uyeki TM, et al. Highly Pathogenic Avian Influenza A(H5N1) Virus Infection in a Dairy Farm Worker. N Engl J Med. 2024 May 3. doi: 10.1056/NEJMc2405371. PMID: 38700506.
- 2024 Cases 1 and 2: Garg S, et al. Outbreak of Highly Pathogenic Avian Influenza A(H5N1) Viruses in U.S. Dairy Cattle and Detection of Two Human Cases - United States, 2024. MMWR Morb Mortal Wkly Rep. 2024 May 30;73(21):501-505. PMID: 38814843.
- 2024 Case 3: https://www.cdc.gov/media/releases/2024/p0530-h5-human-case-michigan.html
- 2024 Case 4: https://www.cdc.gov/media/releases/2024/p-0703-4th-human-case-h5.html
- 2024 4 Cases Among Colorado Poultry Workers: https://www.cdc.gov/media/releases/2024/p-0715-confirm-h5.html
Recommendations
Following is a brief summary adapted from CDC of important clinical information and recommendations related to avian influenza A viruses of public health concern.
Clinicians should consider the possibility of HPAI A(H5N1) virus infection in persons showing signs or symptoms of acute respiratory illness who have relevant exposure history. The CDC recommends the following actions for patients considered to have recent exposure to avian influenza A viruses.
If signs/symptoms compatible with avian influenza A virus infection are present:
- Isolate patient and follow infection control recommendations below.
- Initiate empiric antiviral treatment as soon as possible.
- Notify state/local health department.
- Collect respiratory specimens from the patient to test for avian influenza A viruses at the state health department.
If signs/symptoms compatible with avian influenza A virus infection are not present:
- Follow standard health care facility infection control practices/protocols.
- Investigate other potential causes of the patient’s signs and symptoms.
- Contact state/local health department with any questions or concerns.
Signs/Symptoms of avian influenza A virus infection in humans: Signs/symptoms may include uncomplicated upper respiratory tract signs and symptoms also referred to as influenza-like illness (ILI) [fever ≥100°F plus cough or sore throat], fever (temperature of 100ºF [37.8ºC] or greater) or feeling feverish, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches, fatigue, eye redness (or conjunctivitis), shortness of breath or difficulty breathing. Less common signs and symptoms are diarrhea, nausea, vomiting, or seizures. It is important to remember that infection with influenza viruses, including avian influenza A viruses, does not always cause fever. Fever may not occur in infected persons of any age, particularly in persons aged 65 years and older or people with immunosuppression. The absence of fever should not supersede clinical judgment when evaluating a patient for illness compatible with avian influenza A virus infection.
Infection prevention and control recommendations: Standard Precautions, plus Contact and Airborne Precautions, including the use of eye protection, are recommended when evaluating patients for infection with avian influenza A viruses. If an airborne infection isolation room (AIIR) is not available, isolate the patient in a private room. Health care personnel should wear recommended personal protective equipment (PPE) when providing patient care. These recommendations are consistent with existing infection control guidance for care of patients who might be infected with a novel influenza A virus associated with severe disease. For more information on recommended infection prevention and control measures, please visit Infection Control Within Healthcare Settings for Patients with Novel Influenza A Viruses.
Laboratory testing recommendations: If signs or symptoms consistent with infection with avian influenza A virus are present in a patient with recent exposure to infected birds or contaminated environments, respiratory specimens should be collected for molecular testing (RT-PCR) for influenza viruses, including avian influenza A viruses. For outpatients, upper respiratory tract specimens should be collected. If conjunctivitis is present, conjunctival swabs should be collected. Patients who are severely ill should have both upper and lower respiratory tract specimens collected for influenza testing. For information on specimen collection, infection prevention and control recommendations when collecting specimens, and influenza diagnostic testing, please visit Specimen Collection and Testing for Patients with Novel Influenza A Viruses with Potential to Cause Severe Disease in Humans. Rapid influenza diagnostic tests are not a reliable indicator of avian influenza A virus infection, and the results should not be used to guide infection control or antiviral treatment decisions. Both commercially available rapid influenza diagnostic tests and most influenza molecular assays do not distinguish between infection with seasonal influenza A viruses and avian influenza A viruses. Testing for avian influenza A viruses must be performed at state health department laboratories, and CDC. Testing for other potential causes of acute respiratory illness should also be considered depending upon the local epidemiology of circulating respiratory viruses, including SARS-CoV-2.
Treatment recommendations: Initiation of antiviral treatment with a neuraminidase inhibitor is recommended as soon as possible for any patient with suspected or confirmed infection with an avian influenza A virus. This includes patients who are confirmed cases, probable cases, or cases under investigation, even if more than 48 hours has elapsed since illness onset and regardless of illness severity (outpatients or hospitalized patients). Treatment with oral or enterically administered oseltamivir (twice daily x 5 days) is recommended regardless of time since onset of symptoms. If the patient has been sick for 2 days or less, oral baloxavir treatment is an option. Antiviral treatment should not be delayed while waiting for laboratory test results. If molecular testing is negative for novel avian influenza A virus infection and other influenza viruses, but influenza virus infection is still suspected in a patient who is severely ill, antiviral treatment should be continued and additional respiratory specimens should be collected for repeat influenza testing. For patients who are not hospitalized, if molecular testing is negative for avian influenza A virus and other influenza viruses, antiviral treatment can be discontinued. For more information on treatment recommendations, please visit Use of Antiviral Medications for Treatment of Human Infections with Novel Influenza A Viruses. For pediatric-specific antiviral dosing recommendations, see Red Book, Table 4.10. Non-HIV Antiviral Drugs.
Resources
- AAP: Red Book Influenza Chapter; Table 4.10. Non-HIV Antiviral Drugs
- CDC: Avian Flu
Pediatric Practice Tools and Information Pediatric Pandemic Network: Clinical Guidance for Highly Pathogenic Avian Influenza (HPAI) A(H5N1) CDC: Interim Guidance on Testing and Specimen Collection for Patients with Suspected Infection |
Public Health Resources CDC: Key Public Health Prevention Recommendations for HPAI A (H5N1) CDC: Interim Recommendations for Prevention, Monitoring and Public Health Investigations |
Infection Prevention and Control Resources AAP: Project Firstline CDC: Interim Guidance for Infection Control Within Healthcare Settings |
Information for Patients and Caregivers AAP HealthyChildren.org: Bird Flu: Facts for Families | Available in Spanish |