Research in context
malaria, malaria infection
MALARIA, SECONDARY, MALARIA

Insecticide resistance in malaria vectors is widespread in many endemic settings, thus presenting a serious threat to the efficacy of vector-control tools, mainly long-lasting insecticidal nets (LLINs) and indoor residual spraying. To sustain the progress made against malaria and to improve vector-control tools, WHO recommends the development of new insecticidal products with different modes of action against resistant vectors. Piperonyl butoxide LLINs received interim WHO recommendation as a novel malaria vector-control tool after showing better protection than standard pyrethroid LLINs against malaria infection and transmission in two cluster randomised controlled trials (cRCTs) in Tanzania and Uganda. The current study is a follow-up of the recently published large-scale cRCT assessing the effectiveness and cost-effectiveness against malaria of three types of dual active-ingredient LLINs, compared with pyrethroid-only LLINs in Tanzania. We searched for published papers in English in PubMed on Feb 10, 2022, without restrictions on the date, using the terms “mosquito” or “vectors” and “
This is to our knowledge one of the few large-scale community trials looking at the effectiveness of next-generation dual active-ingredient LLINs on the density of different vector species. Malaria in sub-Saharan Africa is highly heterogeneous due to ecological and climatic variations. Currently, the three main vectors are 
Previous randomised controlled field trials supported by small-scale experimental hut trials have demonstrated the improved effectiveness of dual active-ingredient LLINs compared with standard pyrethroid LLINs on entomological indices. In hut trials, chlorfenapyr pyrethroid LLINs were found effective against several vector species, including A Cochrane review reported that piperonyl-butoxide pyrethroid LLINs had a greater effect on malaria prevalence and mosquito population density than pyrethroid-only LLINs, in areas with high pyrethroid resistance.In this Article, we detailed a secondary analysis from a large cRCT in Tanzania. The primary outcomes reporting the effectiveness of the dual active-ingredient LLINs on malaria indicators and overall vector density over 2 years follow-up have already been published.