Influenza, H5N1

Contact Precautions

Droplet Precautions

Airborne Precautions

Influenza H5N1, also known as avian influenza (flu), mainly infects birds but is also of concern to humans, who have no immunity against it. The virus that causes this infection in birds can mutate and easily infect humans and potentially start a deadly worldwide epidemic. The first avian flu virus to infect humans directly occurred in Hong Kong in 1997 and has since spread across Asia. Prognosis depends on the severity of infection as well as the type of avian flu virus that caused it.

Causes

Highly infective avian flu viruses, such as H5N1, have been shown to survive in the environment for long periods of time, with infection being spread simply by touching contaminated surfaces. Birds who recover from flu can continue to shed the virus in their feces and saliva for as long as 10 days.

Those at risk include farmers, agricultural workers, travelers visiting affected countries, people who eat raw or undercooked poultry, immunocompromised individuals, and health care workers and others who come in contact with patients who have avian flu.

Complications

Complications from avian influenza include conjunctivitis, pneumonia, acute respiratory distress, viral pneumonia, sepsis, organ failure, and death.

Assessment Findings

Symptoms of avian flu infection in humans depend on the particular strain of virus present. With the H5N1 virus, infection causes more classic flu-like symptoms, which might include headache, malaise, dry or productive cough, sore throat, fever above 100.4° F (38° C), runny nose, difficulty breathing, diarrhea, and muscle aches. The patient may also exhibit signs of upper respiratory tract infection, including coryza, pharyngitis and, less commonly, conjunctivitis.

Diagnostic Tests