Pandemic Influenza

Typical Seasonal Flu

Comes from a novel virus to which no one, or few people, have any immunity

Circulating viruses slightly mutate year to year

Attack rate may be as high as 30% of population

Patients are sicker for a longer period time

Illness usually lasts 1 to 2 weeks

Limited vaccine availability

Vaccine available prior to illness in population

May be resistant to some antivirals

Several antiviral medications are available

Excess mortality (3 to 7 times normal rate)

Normal flu mortality – 36,000/year in U.S.

Patients may present with primary viral pneumonia

Pneumonia is usually a later complication

May be severe in all ages

Severe in the very old and the very young

Can occur at any time of the year

Seasonal – occurs in the winter

May have more than one wave of illness

Usually just one wave of illness

Spreads rapidly throughout the world