West Nile virus (WNV) has been detected in Delaware for the first time in 2021 in sentinel chickens, DNREC announced this week. The first finding occurred in northern New Castle County, at a sentinel chicken station sampled by DNRECâs Mosquito Control section on July 19. While there have been no reported WNV cases in humans this year in the state, Delawareans are being reminded that the possibility of contracting mosquito-transmitted diseases, including WNV and Eastern equine encephalitis (EEE), will continue until colder autumn temperatures in mid-October or later. Blood samples are collected by the Mosquito Control section each week from early July into October from the stateâs outdoor-caged sentinel chickens that are humanely housed and handled at 20 monitoring stations statewide, officials noted. The blood samples are tested for WNV and EEE antibodies by the Delaware Public Health Laboratory.