RHIPICEPHALUS-ZAMBEZIENSIS UNLIKELY TO TRANSMIT FOOT-AND-MOUTH-DISEASE VIRUS

The potential of the ixodid tick, Rhipicephalus zambeziensis, was inve stigated as a vector in the transstadial transmission of the foot-and- mouth disease virus by feeding nymphae on viraemic (log 1,0-4,0 TCID50 /ml) cattle. Suspensions were prepared, at various intervals after det achment, from pools of engorged nymphae-some of which were allowed to moult first. Suspensions were inoculated into sucking mice, cell cultu res and, in some cases, cattle to detect the FMD virus. Newly moulted adult ticks, derived from nymphae which had fed on viraemic cattle, we re also allowed to feed on susceptible cattle. The pattern of virus de tection indicated that the FMD virus was capable of surviving at least 3 d in engorged nymphae, but less than 7 d following repletion. It wa s concluded that R. zambeziensis is unlikely to transmit the FMD virus .