Monitoring malaria cases in Kwa-Zulu Natal, South Africa, picked up the failure of pyrethroids in the IRS programme in the 1990s due to P450 mediated pyrethroid-resistance selection in An. funestus, resulting in DDT being successfully reintroduced [46], The resulting decline in malaria was reinforced by a change in drug treatment policy [47]. Here, CYP2B6 is linked to malaria.