Experimental infection of chickens as candidate sentinels for West Nile virus

We evaluated the susceptibility, duration and intensity of viremia, and ser ologic responses of chickens to West Nile (WN) virus (WNV-NY99) infection b y needle, mosquito, or oral inoculation. None of 21 infected chickens devel oped clinical disease, and all these developed neutralizing antibodies. Alt hough viremias were detectable in all but one chicken, the magnitude (mean peak viremia < 10(4) PFU/mL) was deemed insufficient to infect vector mosqu itoes. WNV-NY99 was detected in cloacal and/or throat swabs from 13 of thes e chickens, and direct transmission of WNV-NY99 between chickens occurred o nce (in 16 trials), from a needle-inoculated bird. Nine chickens that inges ted WNV-NY99 failed to become infected. The domestic chickens in this study were susceptible to WN virus infection, developed detectable antibodies, s urvived infection, and with one exception failed to infect cage mates. Thes e are all considered positive attributes of a sentinel species for WN virus surveillance programs.