Abstract:
BACKGROUND : Concerted effort to control malaria has had a substantial impact on the transmission of the disease in
the past two decades. In areas where reduced malaria transmission is being sustained through insecticide-based vector
control interventions, primarily long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS), non-insecticidal
complementary tools will likely be needed to push towards malaria elimination. Once interruption in local disease
transmission is achieved, insecticide-based measures can be scaled down gradually and eventually phased out, saving
on costs of sustaining control programs and mitigating any unintended negative health and environmental impacts
posed by insecticides. These non-insecticidal methods could eventually replace insecticidal methods of vector control.
House screening, a non-insecticidal method, has a long history in malaria control, but is still not widely adopted in subSaharan Africa. This study aims to add to the evidence base for this intervention in low transmission settings by assessing
the efficacy, impact, and feasibility of house screening in areas where LLINs are conventionally used for malaria control.
METHODS : A two-armed, household randomized clinical trial will be conducted in Mozambique, Zambia, and
Zimbabwe to evaluate whether combined the use of house screens and LLINs affords better protection against clinical
malaria in children between 6 months and 13 years compared to the sole use of LLINs. Eight hundred households will
be enrolled in each study area, where 400 households will be randomly assigned the intervention, house screening,
and LLINs while the control households will be provided with LLINs only. Clinical malaria incidence will be estimated
by actively following up one child from each household for 6 months over the malaria transmission season. Crosssectional parasite prevalence will be estimated by testing all participating children for malaria parasites at the
beginning and end of each transmission season using rapid diagnostic tests.
CDC light traps and pyrethrum spray catches (PSC) will be used to sample adult mosquitoes and evaluate the impact
of house screening on indoor mosquito density, species distribution, and sporozoite rates.
