Mosquito pool samples collected Aug. 5 from two Northfield locations have tested positive for West Nile virus, the Atlantic County Division of Public Health said.The samples were collected from the 100 block of Northwood Court and the 1200 block of Zion Road.West Nile was previously confirmed this year in samples collected from Linwood, Pleasantville and Ventnor as well as the Zion Road site in Northfield.