The rate at which a disease agent may be spread by its vector (the vectorial capacity) is mainly a function of the following variables:

• the vector density in relation to its host
• the vector's life expectancy
• the frequency with which the vector bites the host
• the duration from the infection of the vector to its infectivity (i.e. the latent period of the disease agent in the vector)

Dengue mosquitoes are able to transmit dengue even if they occur only in very low densities. (Picture from Goeldi, 1905.)

In field tests in Cairns, Australia and Belo Horizonte, Brazil, the BG-Sentinel trap collected up to 29 female Aedes aegypti per day per premise under real life conditions in urban areas (Kröckel et al. in press 2006, Williams et al. in press).

With catching rates like this, the BG-Sentinel should have a substantial impact on the vectorial capacity, thus leading to a significant reduction of the risk of transmission.