Timeliness of enteric disease surveillance in 6 US states. - Hedberg CW; Greenblatt JF; Matyas BT; Lemmings J; Sharp DJ; Skibicki RT; Liang AP; Enteric Disease Investigation Timeline Study Work Group; Hedberg, Craig W; Greenblatt, Jesse F; Matyas, Bela T; Lemmings, Jennifer; et al. (Emerging Infectious Diseases, 2008)