1 New York (JFK) JFK has over 1,000 daily flights, connecting some 200 airports in more than 60 countries. The number of international connections allows passengers here to come in contact with individuals from many points of origin, dramatically increasing the risk that infected travelers could pass disease to uninfected populations worldwide.
2 Los Angeles (LAX) Los Angeles International has lots of traffic,
supporting more than 1,400 flights a day
and connecting some
3 Honolulu (HNL) Honolulu International gets only two-fifths of JFK’s traffic, yet it poses a major risk because it has a high proportion of long-distance flights, links to well-connected airports, and a geographic location that encourages an equal diffusion of travelers
going east and west.
4 San Francisco (SFO)
5 Newark, NJ (EWR)
6 Chicago (ORD)
7 Washington, D.C., Dulles (IAD)
8 Atlanta (ATL) While Hartsfield-Jackson Atlanta International ranks first in the world for traffic (roughly 2,600 flights a day), most of these flights are regional, leaving the airport relatively unconnected to far-off locations that would boost its ability to spread infection.
The highlighted route shows two trips, one from San Francisco to New Orleans and back, the other following the same route with a layover in Chicago. This is a typical itinerary: The traveler moves to and from a home base in a major city, either through direct flights or incorporating stopovers. Passengers remain at a destination an average of four days—a crucial data point, since a disease’s transmission rate depends on the duration of exposure.