Incompetence of Domestic Pigs as Amplifying Hosts of Vesicular Stomatitis Virus for Lutzomyia shannoni (Diptera: Psychodidae)

Seven domestic pigs, Sus scrofa L., were infected by intradermal inoculation at 3 different sites with the New Jersey serotype of vesicular stomatitis (VSNJ) virus. Laboratory-reared Lutzomyia shannoni Dyar sand flies, a suspected biological vector of VSNJ virus, were allowed to feed on pigs at the lower abdomen or at sites of their own selection on days 1-7 and on day 10 postinfection. Blood samples were taken from infected swine concomitant with most feeding trials and tested for the presence of virus. Sand flies were held for up to 5 d following ingestion of blood and tested for VSNJ virus infection. Virus was not recovered from the blood of infected pigs or from any of the flies that fed on these pigs. The findings suggest that domestic pigs do not fulfill the traditional concept of amplifying hosts of VSNJ virus.