Influenza Diagnosis and Treatment : Impact of New Antivirals on Perceived Treatment Behaviours during Recent Influenza Outbreaks

In the past patients and doctors have often underestimated the serious nature and impact of influenza outbreaks. Our aim was to determine current perceptions and behaviours among the general public and physicians regarding influenza illness and its treatment in the US, Japan and Europe during two influenza seasons (1999/2000 [99/00] and 2000/2001 [00/01]). A survey was conducted among patients (n = 7583 in 99/00 and n = 7790 in 00/01) and physicians (n = 609 in 99/00 and n = 808 in 00/01). Patients recognise influenza as a severe illness, identifying it by signs and symptoms of high fever, chills and feverishness, muscle aches/pains and cough. Similarly, physicians use these signs and symptoms to clinically diagnose influenza. Physicians report that most consulting patients (53-93%) would present within 2 days of the onset of symptoms, i.e. within the time needed to receive maximum treatment benefit from the newer antivirals. However, most prescriptions or recommendations for influenza treatment in Europe were for antibiotics (30%) and analgesics or antipyretics (100%). Antivirals were recommended by only 10% of European doctors, compared with 45% of US physicians. In the past two influenza seasons the percentage of doctors using antivirals appropriately has increased from 47 to 62%. Antibiotic use in the US during the two seasons fell from 25 to 11%. Specific antiviral treatments are not yet widely used in Europe, but our survey in the US suggests that with the high and early consultation rates and prompt outbreak information they may be used effectively to reduce the influenza burden.