RNAi modulates DENV replication at different infection stages since knock-down of the siRNA machinery factors dcr-2, r2d2 and ago-2 in Ae. aegypti mosquitoes prior to an infectious blood meal affects infection prevalence, dissemination of the virus from the midgut to the salivary glands, viral titer and viral transmission via the saliva (Sánchez-Vargas et al., 2009). This evidence concerns the gene AGO2 and infection.