1. Outbreaks Epidemics Pandemics
Microbiology
Outbreaks
Epidemics
Pandemics

2. Outbreaks Definition – A sudden rise in the incidence of a disease.
Rate of infection – A disease outbreak happens when a disease occurs in greater numbers than expected in a community or region or during a season.
An outbreak may occur in one community or even extend to several countries. It can last from days to years.
Examples –
E. Coli outbreak at NC State Fair – 2011
Potato Blight in NC

3. Epidemic
Definition - A widespread occurrence of an infectious disease in a community at a particular time.
Rate of infection - An epidemic occurs when an infectious disease spreads rapidly to many people.
Examples –
Polio Epidemic 1944

4. Pandemic Definition - A pandemic is a global disease outbreak.
Rate of Infection – When a disease can reach all parts of the world in 6 to 9 months.
Examples –
Spanish influenza killed million people in 1918.
Hong Kong influenza killed 1 million people in 1968
HIV/AIDS – killed over 39 million people