INFLUENCE OF DOSE AND ROUTE ON TRANSMISSION OF ENCEPHALOMYOCARDITIS VIRUS TO SWINE

The susceptibility of swine to infection with encephalomyocarditis vir us (EMCV) was assessed. Transmission of EMCV in a single exposure by g avage or intranasal routes was highly dose dependent. In a direct comp arison, animals were exposed to EMCV by gavage, intranasal, intramuscu lar, intratracheal, or transdermal routes. A higher proportion of anim als exposed by transdermal (5/5), intratracheal (5/5), or intramuscula r (5/5) routes than those exposed by intranasal (2/5) or gavage (3/5) routes became infected. The large quantity of virus required to infect animals intranasally or orally suggests that transmission by these ro utes may not occur routinely in the field. Transmission of EMCV by wou nd contamination (transdermally) has not been reported previously. Alt hough EMCV was recovered from rectal, external genitalia, and pharynge al swabs, there was no evidence of pig-to-pig transmission of EMCV fro m experimentally infected animals to comingled sentinels.