A simple technique for demonstrating transmission of dengue virus by mosquitoes without the use of vertebrate hosts.

Aedes albopictus mosquitoes infected with dengue type 2 virus transmitted virus to measured small amounts of fluid which could be titrated readily for virus content. It was found that the percentage of mosquitoes transmitting was related to the extent of salivary gland infection. It was not uncommon for mosquitoes to transmit as much as 10(4) mosquito infectious doses50 of virus and transmission of significant amounts of virus was observed even though an insect only probed the test suspension without feeding to repletion. Transmission of virus was demonstrated as early as 10 days after oral infection when mosquitoes were held at 32 degrees C.