Effectiveness and cost-effectiveness against malaria of three types of dual-active-ingredient long-lasting insecticidal nets (LLINs) compared with pyrethroid-only LLINs in Tanzania: a four-arm, cluster-randomised trial thelancet.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from thelancet.com Daily Mail and Mail on Sunday newspapers.