Key Points:
- H5N5 Bird Flu Strain prompts heightened global surveillance after new detections in wild bird populations.
- Health authorities assess transmission risks as cases emerge across multiple regions.
- Researchers intensify monitoring to prevent potential spread to poultry and reduce economic impact.
A Washington man has died from a rareH5N5 Bird Flu Strain Strain, marking what health officials believe is the first known human fatality linked to the H5N5 virus. State authorities confirmed the death on Nov. 23 and said they are monitoring individuals who had close contact with the man.
State Confirms First Known Human Case
The Washington State Department of Health said the man, an older adult from Grays Harbor County, tested positive for H5N5 while receiving treatment for severe respiratory illness. The county is about 125 kilometers southwest of Seattle. Officials said he had pre-existing health conditions and kept a backyard flock of domestic poultry.
According to the department, investigators suspect the birds may have been exposed to wild birds carrying the virus. “The risk to the public remains low,” state health officials said. “No other people involved have tested positive for avian influenza.”
Monitoring of Close Contacts Continues
Health authorities said they are tracking anyone who interacted closely with the man. At this time, officials reported “no evidence of transmission of this virus between people.” Earlier in November, the Centers for Disease Control and Prevention issued a statement noting that available information did not indicate an increased risk to public health.
H5N5 Bird Flu Strain is considered less concerning for humans than H5N1, the strain associated with a wave of infections among dairy and poultry workers in 2024 and 2025. The United States recorded 70 human H5N1 cases during that period, most of them mild. Scientists said H5N5 differs from H5N1 due to a protein that helps the virus release itself from infected cells and spread to surrounding tissue.
Background on Symptoms and Transmission
Health agencies continue to outline how H5N5 Bird Flu Strain affects humans. According to national health guidance, symptoms can appear quickly and include high fever, muscle aches, headache, and respiratory difficulties such as coughing or shortness of breath. Early symptoms may also involve diarrhoea, vomiting, stomach pain, chest pain, nose and gum bleeding, or conjunctivitis. In most cases, symptoms develop three to five days after infection.
Severe complications may emerge within days, including pneumonia and acute respiratory distress syndrome. Human-to-human transmission has not been documented in Europe or the UK but has occurred in limited cases elsewhere.
H5N5 Bird Flu Strain typically spreads through direct contact with infected birds, either dead or alive. This includes touching birds, handling droppings or bedding, and killing or preparing infected poultry for cooking. Health officials often emphasize that individuals who work closely with birds—such as farm workers, poultry handlers, and people maintaining backyard flocks—face higher exposure risks.
Broader Context and Ongoing Response
Washington authorities said surveillance efforts will continue as laboratories analyze viral samples. They added that veterinarians are assessing the man’s poultry to determine how the virus entered the flock spreading H5N5 Bird Flu Strain.
Federal officials have urged states to remain alert for unusual respiratory illnesses in people who work with birds. In guidance issued this year, the Centers for Disease Control and Prevention recommended that clinicians consider avian influenza testing for patients with compatible symptoms and recent bird exposure.
Scientists tracking avian influenza said the identification of an H5N5 Bird Flu Strain in a human underscores the importance of monitoring virus evolution. While H5 strains circulate widely among wild birds, only a few subtypes have infected humans. Most cases occur when the virus spreads from birds to people during close contact.
Public health teams in Washington said they will provide updates as testing and monitoring continue. For now, officials maintain that the fatal H5N5 Bird Flu Strain case does not indicate broader transmission risk.
