Mosquito-Borne Disease Surveillance

West Nile Virus Statistics

Category	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019*
Positive Dead Birds	1	0	0	2	0	0	0	0	0	1	0
Positive Horses	0	0	3	0	0	3	1	0	0	2	1
Positive Mosquito Samples	51	186	9	168	139	218	97	95	228	138	411

Statistics provided by Environmental Services.
*Maricopa County Environmental Services Department's PCR testing results, as of August 20, 2019.

Category	2015	2016	2017	2018	2019*
Positive Mosquito Samples	60	0	160	106	193

Statistics provided by Environmental Services.
* MCESD's PCR testing results, as of August 20, 2019.