H5N1 avian influenza: what to know

H5N1 is a subtype of influenza A that circulates mainly among birds and other animals. Human infection is uncommon but can follow close contact with infected animals, contaminated environments, or materials. Illness may involve fever, chills, cough, headache, fatigue, and feeling generally unwell. Eye irritation or breathing symptoms can occur. Symptoms alone cannot establish H5N1, so exposure history and clinical testing are important. Pneumonia is a serious lung complication that needs urgent assessment.

Do not touch sick or dead birds or animals, and avoid contact with animal droppings or contaminated surfaces. If contact has occurred, wash hands and follow local public-health or clinical advice. If you develop fever, cough, eye symptoms, or unusual tiredness after possible exposure, contact a healthcare service promptly and mention the exposure before attending in person. Follow instructions about testing, isolation, and treatment.

Seek emergency help for difficulty breathing, severe chest pain, confusion, collapse, or blue or grey lips. Prompt assessment is needed for worsening cough, persistent fever, dehydration, or rapidly increasing weakness after a possible animal exposure. Do not wait for symptoms to become severe before reporting a relevant exposure to a clinician or public-health service.

Tell the clinician what animal or environment was involved, when contact happened, and whether protective equipment was used. Ask whether testing, monitoring, treatment, or precautions for household contacts are needed, and which symptoms should prompt emergency care.