Vesicular stomatitis virus (Indiana serotype): transovarial transmission by phlebotomine sandlies

Transovarial transmission of vesicular stomatitis virus (Indiana serotype) by experimentally infected Lutzomyia trapidoi and Lutzomyia ylephiletrix to their progeny was demonstrated. Virus was recovered from all developmental stages; mean virus titers from egg to first generation adult showed a four-log increase, indicating that virus multiplication occurred during development of the sandflies. Virus titers in first generation adult females were comparable to those found in their parents. These infected female sandflies transmitted vesicular stomatitus virus Indiana by bite to susceptible animals and transmitted the virus transovarially to their offspring (second generation). Results demonstrate a possible mechanism for transmission and maintenance of this virus in nature without a vertebrate (heat) host reservoir.