Effect of Disodium Phosphonoacetate and Iododeoxyuridine on the Multiplication of African Swine Fever Virus <i>in vitro</i>

Disodium phosphonoacetate (PAA) was found to inhibit the replication of African swine fever virus (ASFV). The action of this compound has been compared with the inhibitory capacity of iododeoxyuridine (IDU) upon ASFV growing in Vero cells. The study was done by the immunofluorescence technique in order to detect formations of cytoplasmic virus antigens and inclusion bodies; both were found to be inhibited by IDU and PAA. At 100 microgram/ml, IDU blocked completely the multiplication of ASFV and with PAA, a few scattered cells showed positive fluorescence. The infectivity of the virus was reduced 1--5 log depending upon drug concentrations and time of exposure to the drugs. Inhibition of ASFV replication by PAA suggests that this virus, like other herpesviruses, involves a virus-specific DNA polymerase in its replication mechanism.