2017 provisional data for the United States

Chikungunya virus disease became a nationally notifiable condition in 2015. Cases are reported to CDC by state and local health departments using standard case definitions.
As of October 17, 2017, a total of 63 chikungunya virus disease cases with illness onset in 2017 have been reported to ArboNET from 22 U.S. states (Table & Map). All reported cases occurred in travelers returning from affected areas. No locally-transmitted cases have been reported from U.S. states.
A total of 32 chikungunya virus disease cases with illness onset in 2017 have been reported to ArboNET from U.S. territories (Table). To date, 32 locally acquired cases have been reported from Puerto Rico.

States reporting chikungunya virus disease cases – United States, 2017 (as of October 17, 2017)

	Travel-associated cases No. (%)	Locally-transmitted cases No. (%)
State	(N=63)	(N=0)
Alaska	1 (2)	0 (0)
California	9 (14)	0 (0)
Colorado	1 (2)	0 (0)
Georgia	1 (2)	0 (0)
Hawaii	2 (3)	0 (0)
Illinois	3 (5)	0 (0)
Iowa	1 (2)	0 (0)
Kansas	1 (2)	0 (0)
Louisiana	1 (2)	0 (0)
Maine	1 (2)	0 (0)
Maryland	1 (2)	0 (0)
Massachusetts	3 (5)	0 (0)
Michigan	2 (3)	0 (0)
Nebraska	2 (3)	0 (0)
New Jersey	6 (10)	0 (0)
New York	9 (14)	0 (0)
Ohio	3 (5)	0 (0)
Pennsylvania	1 (2)	0 (0)
Texas	8 (13)	0 (0)
Virginia	3 (5)	0 (0)
Washington	1 (2)	0 (0)
Wisconsin	3 (5)	0 (0)

Territories	(N=0)	(N=32)
Puerto Rico	0 (0)	32 (100)