AGO2 and infection: Ago2 is known to be critical for the antiviral activity of the exo-siRNA pathway in vitro, moreover mosquitoes without Ago2, or where Ago2 has been experimentally silenced, are more susceptible to arbovirus infection and infection of mosquitoes lacking Ago2 resulting in increased mortality of the arthropod (7, 10, 27, 32, 35).