Permethrin-Treated Baby Wraps for the Prevention of Malaria

Malaria remains a major cause of childhood death in sub-Saharan Africa. We leveraged the traditional practice of mothers carrying children on their backs in cloth wraps to assess whether treating the wraps with an insect repellent might provide a layer of protection against malaria.

In a double-blind, randomized, placebo-controlled trial conducted in Uganda, we enrolled adult women with a child who was 6 to 18 months of age. The mother-child pairs were randomly assigned in a 1:1 ratio to use permethrin-treated wraps (intervention group) or sham-treated wraps (control group). The wraps underwent retreatment every 4 weeks. All the participants received a new, pyrethroid-only long-lasting insecticide-treated bed net. The participants visited the trial clinics every 2 weeks for 24 weeks and made unscheduled visits in the case of febrile illness in the children. The primary outcome was clinical malaria in the children, as defined by fever and a positive malaria rapid diagnostic test.

From June 2022 through April 2024, a total of 419 mother-child pairs were screened, and 400 underwent randomization; 200 pairs were assigned to the intervention group and 200 to the control group. Clinic attendance was high (5194 of 5200 planned visits [99.9%] were attended), and no participants were lost to follow-up. The incidence rate of clinical malaria was 0.73 cases per 100 person-weeks (95% confidence interval [CI], 0.51 to 1.02) in the intervention group and 2.14 cases per 100 person-weeks (95% CI, 1.73 to 2.62) in the control group (incidence rate ratio, 0.34; 95% CI, 0.23 to 0.51; P<0.001). Rash was reported more often in the intervention group than in the control group (8.5% vs. 6.0% of participants).

Among mother-child pairs who had access to bed nets, maternal use of permethrin-treated baby wraps significantly reduced the incidence of clinical malaria in the children. (Funded by the Doris Duke Foundation and others; ClinicalTrials.gov number, NCT05391230.).