Table 2. WNV surveillance plan (sampling and testing) in 2015.

	Lower-risk districts												High-risk districts
Testing of sentinel horses for WNV IgM antibodies (ELISA)
Sentinel horses	- up to 30 horses - minimum of 7 localities per district - testing on four occasions (one per month in June, July, August and September)												- up to 50 horses - minimum of 10 localities per district - testing on four occasions (one per month in June, July, August and September)
Real-time RT-PCR detection of WNV in natural reservoirs and vectors
Wild birds	- up to 50 dead wild birds found during the period of May—October												- all found dead throughout the year, or - up to 100 samples of purposely shot or live-trapped susceptible bird species during the period of May—October
Mosquitoes (Culex pipiens)	- collection at monthly intervals - 5 localities per district - 5 samplings from June to September (2 samplings in July)												- collection at 2-week intervals - 10 localities per district - 7 samplings from June to September
Sampling strategy
Sampling distribution	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Horses
Mosquitoes
Wild birds