Simulation of a pandemic flu outbreak in the continental United
States, initially introduced by the arrival of 10 infected individuals
in Los Angeles.
The spatiotemporal dynamics of the prevalence (number of symptomatic
cases at any point in time), is shown on a logarithmic color scale,
from 1 or fewer (blue) to 100 or more (red) cases per 1,000 persons.
Without mitigation strategies, the entire nation becomes infected
within a few months.
Depending on the reproductive number R0, effective intervention
strategies can be successful without resorting to economically
damaging measures like school closure, quarantine, and work or
This large-scale agent-based simulation involves 280 million people,
and uses demographic and worker flow data at the Census tract
level, as well as long-range travel statistics, to describe the
geographic movement of people. In this simulation, long-range
travel is assumed to occur at a lower-than-normal rate (10 percent)
due to travel advisories, but with no other mitigation strategies
the pandemic quickly spreads nationwide, peaking about 90 days
after the initial introduction.
Blue: Few or none of the population is showing symptoms,
more precisely 1 or fewer per 1000 persons.