Pandemic Versus Seasonal Outbreak of Avian Flu
Scientists are worried that avian flu could become an influenza pandemic. An pandemic is different from a seasonal outbreak, or "epidemic," of influenza. Seasonal outbreaks are caused by subtypes of influenza viruses that already circulate among people, whereas influenza pandemic outbreaks are caused by:
- New subtypes
- Subtypes that have never circulated among people
- Subtypes that have not circulated among people for a long time.
Past influenza pandemics have led to high levels of illness, death, social disruption, and economic loss.
The reported symptoms of avian flu in humans have ranged from typical influenza-like symptoms (fever, cough, sore throat, and muscle aches) to eye infections (conjunctivitis), acute respiratory distress, viral pneumonia, and other severe, life-threatening complications.
Prevention and Treatment of Avian Flu
Vaccines to protect humans against H5N1 avian flu are currently under development. In addition, research is underway on methods to make large quantities of vaccine more quickly. So far, research suggests that two antiviral medicines, oseltamivir (Tamiflu®) and zanamivir (Relenza®), may be useful treatments for H5N1. However, these viruses are generally resistant to two other available antiviral medications, amantadine and rimantadine, which cannot be used to treat avian flu.