Tiono AB, et al. - Researchers performed a cluster-randomised controlled trial to evaluate the efficacy of bednets containing permethrin, a pyrethroid, and pyriproxyfen, an insect growth regulator, vs permethrin-only (standard) long-lasting insecticidal nets (LLINs) against clinical malaria in children younger than 5 years in Banfora, Burkina Faso. Results of this study suggested that permethrin plus pyriproxyfen (PPF) -treated LLINs give more protection against clinical malaria than do standard LLINs and could be utilized as an alternative to standard LLINs in areas with intense transmission of Plasmodium falciparum malaria and highly pyrethroid-resistant vectors.

Methods

• It was a two-group, step-wedge, cluster-randomised, controlled, superiority trial.
• For this trial, standard LLINs were incrementally replaced with LLINs treated with PPF in 40 rural clusters in Burkina Faso.  
• Fifty children (aged 6 months to 5 years) were followed up by passive case detection for clinical malaria in each cluster.
• At the start and the end of the transmission seasons in 2014 and 2015, cross-sectional surveys were done.
• Monthly collections from indoor light traps was performed to estimate vector densities.
• The incidence of clinical malaria, measured by passive case detection, and the entomological inoculation rate were the primary endpoints.
• Analyses were adjusted for clustering and for month and health centre.

Results

• According to the findings obtained, 1980 children were enlisted in the cohort in 2014 and 2157 in 2015.
• More than 99% of children slept under a bednet at the end of the study.
• It was observed that the incidence of clinical malaria was 2·0 episodes per child-year in the standard LLIN group.
• In addition, the incidence of clinical malaria was 1·5 episodes per child-year in the PPF-treated LLIN group (incidence rate ratio 0·88 [95% CI 0·77–0·99; p=0·04]).
• They found that the entomological inoculation rate was 85 (95% CI 63–108) infective bites per transmission season in the standard LLIN group compared to 42 (32–52) infective bites per transmission season in the PPF-treated LLIN group (rate ratio 0·49, 95% CI 0·32–0·66; p < 0·0001).