Dengue virus can interfere with RNA interference (RNAi) pathways via two distinct mechanisms. Dengue virus infection results in production of a subgenomic flavivirus RNA (sfRNA) from the 3'-untranslated region of the genome that can inhibit cleavage of double-stranded RNA (dsRNA) by the dicer enzyme.66 Dengue virus infection is also able to suppress the RNAi pathway by expression of NS4B