Interventions against Aedes/dengue at the household level: a systematic review and meta-analysis

Abstract

Background: Because the evidence for the role of structural housing and combinations of interventions (domestic or peri-domestic) against Aedes mosquitoes or dengue is still lacking, this systematic review and meta-analysis aimed to analyse and synthesize research focusing on the household as the unit of allocation.

Methods: We searched MEDLINE, LILACS, and Web of Science databases until February 2023 using three general keyword categories: (1) "Aedes" or "dengue"; (2) structural housing interventions including "house", "water", or "drainage"; and (3) vector control interventions of potential relevance and their combinations. We performed a qualitative content analysis and a meta-analysis for 13 entries on dengue seroconversion data.

Findings: 14,272 articles were screened by titles, 615 by abstracts, 79 by full-text. 61 were selected. Satisfactory data quality allowed for detailed content analysis. Interventions at the household level against the immature mosquito stages (21 studies, 34%) showed positive or mixed results in entomological and epidemiological outcomes (86% and 75% respectively). Combined interventions against immature and adult stages (11 studies, 18%) performed similarly (91% and 67%) while those against the adult mosquitoes (29 studies, 48%) performed less well (79%, 22%). A meta-analysis on seroconversion outcomes showed a not-statistically significant reduction for interventions (log odds-ratio: -0.18 [-0.51, 0.14 95% CI]).

Interpretation: No basic research on housing structure or modification was eligible for this systematic review but many interventions with clear impact on vector indices and, to a lesser extent, on dengue were described. The small and not-statistically significant effect size of the meta-analysis highlights the difficulty of proving effectiveness against this highly-clustered disease and of overcoming practical implementation obstacles (e.g. efficacy loss, compliance). The long-term success of interventions depends on suitability, community commitment and official support and promotion. The choice of a specific vector control package needs to take all these context-specific aspects into consideration.

Funding: This work was funded by a grant from the World Health Organization (2021/1121668-0, PO 202678425, NTD/VVE).

Keywords: Aedes; Aedes-borne diseases; Dengue; Housing; Meta-analysis; Systematic review; Vector control.

Fig. 1

PRISMA flow diagram for study selection, adapted from Page et al., 2020; numbers include original search done + update of searches done from January to February 2023.

Fig. 2

Geographical locations of selected studies, with number of studies per country.

Fig. 3

Timeline of studies with number and type of interventions indicated. A study may include more than one intervention.

Fig. 4

Overview of the characteristics of the included studies. ∗Venezuela, Mexico, Peru, Kenya, Thailand, Myanmar, Vietnam, Philippines. Colours are visual aids with no additional significance; ^a RCT = randomized control trial, Iv.C = intervention vs control, B&A = before and after intervention, Q-ex = quasi-experimental; ^bAedes: 1 = aegypti, 2 = albopictus, 3 = both, 4 = not specified; ^c Rural/urban: 1 = rural, 2 = semi-rural, 3 = urban, 4 = urban-high rises; ^d Intervention type: 1 = immature stages (eggs, larvae, pupae), 2 = adult mosquito. 3 = both; ^e Results (reductions are expected): 0 = no statistical differences between intervention and control, −1 and 1 = statistical differences, respectively with worse or better outcome in intervention group, 0&1 = mixed results depending on indicator or geographical area, NDt = not detected; ^fSustainability: 0 = effect no longer observed, 1 = effect still observed; X = measured but not applicable because treatment was ineffective; Other categories: 1 = “yes” or in the study. The total indicates the number of occurrences in a column regardless of values and the percentage is computed for N = 61.

Fig. 5

Forest plot with 13 entries from 11 studies sorted by ascending values of dengue incidence in the control arm (indicated in parenthesis).