Map showing the An. minimus s.l ., An. epiroticus , An. dirus s.s . and An. subpictus populations analysed in this study. All An. minimus s.l., An. epiroticus and An. subpictus populations, except the VHBA, VHBB and VSLB An. minimus populations, were resistant or possible resistant to DDT and/or pyrethroids. Although, the An. dirus s.s. populations were DDT and pyrethroid susceptible, these populations showed high levels of variation in mean knockdown time (KDT50) (ranged from 8 till 31 minutes for DDT and from 8 till 24 minutes for pyrethroids). Mosquitoes of the Anopheles populations indicated on the map were further analysed for the presence of kdr mutations. The pyrethroid and DDT resistant An. minimus s.l., An. epiroticus and An. subpictus populations of Vietnam were additionally subjected to biochemical assays.