Amitraz Effects on Foot-and-Mouth Disease Virus in Mammalian Cellsin Vitro

The toxicity of the acaricide amitraz and its effect on foot-and-mouth disease virus multiplication were evaluated in IB-RS-2 cellsin vitro.A reduction of cell growth rate that was dependent on the dose and the length of treatment was observed in cells exposed to amitraz concentrations ranging from 20 to 50 μg/ml. Foot-and-mouth disease virus infectivity remained essentially unchanged in cells exposed to amitraz (20 μg/ml) 24 hr prior to virus infection or after the adsorption period. Viral RNA synthesis evaluated through [3H]uridine incorporation in cells treated for 24 hr prior to infection was not affected by amitraz.