PANDEMIC FLU FAQs

How do pandemic flu viruses develop?

New flu viruses develop when a biological process called antigenic shift—which causes a sudden and major change in influenza A viruses—occurs.

Antigenic shift can occur when proteins on the surface of the virus change in new ways due to:

• mutation
• exchange of genetic material between multiple influenza viruses

If antigenic shift creates a new flu virus that causes severe disease in humans and spreads easily from person-to-person, a pandemic flu can occur.[13]

 
Important Safety Information About RELENZA

• Serious cases of bronchospasm, including fatalities, have been reported during treatment with RELENZA in patients with and without underlying airway disease. Many of these cases were reported during postmarketing, and causality was difficult to assess
  
• RELENZA SHOULD BE DISCONTINUED IN ANY PATIENT WHO DEVELOPS BRONCHOSPASM OR DECLINE IN RESPIRATORY FUNCTION; immediate treatment and hospitalization may be required
  
• Safety and efficacy have not been demonstrated in patients with high-risk underlying medical conditions
  
• Patients should be instructed in the use of the delivery system. Instructions should include a demonstration whenever possible
  
• If treatment with RELENZA is considered for a patient with underlying airway disease, the potential risks and benefits should be carefully weighed. If a decision is made to prescribe RELENZA for such a patient, this should be done only under conditions of careful monitoring of respiratory function, close observation, and appropriate supportive care including availability of fast-acting bronchodilators
  
• Common adverse events in treatment and prophylaxis studies with RELENZA were nausea, diarrhea, sinusitis, viral respiratory infections, headaches, nasal signs and symptoms. The incidence of these adverse events was similar in both groups for RELENZA and placebo-treated groups
  
• Please see complete Prescribing Information for RELENZA