Table 2. Vector control tools for Aedes mosquito control.
Strength of evidence is based only on recent systematic reviews and meta-analysis studies carried out in the last 5 years. We used scores to rank the ‘strength of evidence’ based on study designs used for assessing the efficacy of vector control interventions as proposed by Wilson and colleagues (2015) for epidemiological trials (1, 2a, 2b). We created 2 new ‘levels of evidence’ (3a and 3b) to distinguish randomised versus nonrandomised (observational) ‘entomology’ trials.
| Stage/scenario | Methodology | Type of intervention/product | Strength of evidence* | Constraints/advantages | Specifications | References |
|---|---|---|---|---|---|---|
|
Adult control in emergency S2, S3, S4, and S5 |
Insecticide spraying | Space spraying (indoors, outdoors) | Epidemiological evidence for ISS based on observational studies (level 2b). Several entomological studies (level 3a and 3b) for ISS and OSS. | Insecticide resistance Low acceptability and limited sense of security in the community Poor persistence Regulatory and environmental constraints Needs skilled, experienced staff |
Thermal fogging or cold fogging (ULV spray) using WHO-recommended insecticides Indoor house-to-house application using portable sprayer. Outdoor applications (i.e., vehicle-mounted fogger) if mosquitoes are exophilic and exophagic. Applications should be carried out at the right time, in the right place and according to prescribed instructions. |
[13, 29, 31, 32, 34, 48, 58, 59] |
| Residual spraying (indoors or outdoors) | Epidemiological evidence of IRS (level 2a). Entomological evidence (level 3b) for IRS for A. aegypti and ORS for A. albopictus (level 3b). | Insecticide resistance Costly and time-consuming Requires high coverage Needs skilled, experienced staff |
TIRS for indoor resting A. aegypti ORS on the vegetation against A. albopictus Application by portable compression sprayers |
[29, 31, 34, 35, 59, 60, 61] |
||
| Adult control for routine and emergency S4 and S5 | Mass trapping | Gravid traps (AGO or GAT) | Epidemiological evidence based on observational studies (level 2b). Entomological evidence (level 3b) for A. aegypti. | Low cost Possible to combine with community participation Sustainable, able to be reused for several seasons |
Need for a coverage of greater than 80% Use large autocidal gravid traps, as AGO or GAT, to maximise visual and olfactory attraction using grass or hay infusion |
[36, 62, 63] |
| Adult control for routine and emergency S4 and S5 | Personal protection | Topical repellents (applied directly onto the skin) | Absence of epidemiological and entomological evidence as a part of control campaigns. | Individual-based action (requires high degree of compliance) No residual activity |
DEET, the longest-lasting; IR3535 or picaridin, medium-long lasting protection; plant-derived oils (eucalyptus, citronella, or geranium), short-term (frequency of applications according to national legislation and/or manufacturer’s recommendations) | [29, 64] |
| Insecticide-treated materials (clothes, curtains, house screens, water container covers, etc.) | Epidemiological evidence for house screening (level 2b). Entomological evidence for ITCs, house screening, and water container covers (level 3a and 3b). No evidence for bed nets. | Individual- and community-based action Residual activity with long-lasting technology Insecticide resistance Low protection against UV Degradation of insecticide |
Clothes, curtains, and bed nets treated with WHO-recommended insecticides. Most evidence supports house screening for preventing dengue transmission |
[29, 65, 66] | ||
|
Larval control for routine S2, S3, S4, and S5 |
Environmental management | Source reduction and educational outreach visits (door-to-door) | Epidemiological evidence (level 1) of community based campaigns. Entomological evidence (level 3a and 3b). | Labour intensive. Larval development habitats need to be accurately identified. Must be done diligently and conscientiously and with access to a high number of dwellings |
Requires a high level of education and community participation. Difficult to sustain over time. Need to characterise larval development habitats, including urban cryptic habitats. Essential to reduce mosquito larval development habitats in the long-term in private and public domains |
[29, 40, 41, 43, 48, 58, 67] |
| Larviciding | Organophosphates (Temephos, Chlorpyrifos, Pirimephos methyl, Fenthion) | Entomological evidence for Temephos (level 3b). | Affordable Not acceptable for treating drinking water containers and sources (except Temephos) Temephos resistance in several areas Regulatory constraints (e.g., OPs are not notified in the EU for mosquito control) |
Cholinesterase inhibitors Different formulations (EC, GR) and application methods (manual or with hand sprayers) |
[41, 68] | |
| Insect growth regulators (pyryproxifen, diflubenzuron, novaluron) | Epidemiological evidence for pyryproxifen as part of community base (level 2b). Entomological evidence (level 3b). | More expensive Late acting effect (pupae) on juvenoids Acceptable for treating drinking water sources and containers Constraints for the treatment of cryptic breeding sites |
Disruption of endocrine system for juvenoids (pyriproxyfen) and chitin synthesis inhibitor for ecdysoids (novaluron and diflubenzuron) Different formulations (WG, GR, DT) and application methods (manual or with hand sprayers) |
[29, 39] | ||
| Bti | Entomological evidence (level 3a and 3b) for Bti. | No resistance Selective and safe Acceptable for treating drinking water sources and containers Low residual action in polluted habitats |
Bacterial toxins targeting midgut epithelium cells Different formulations (WG, GR) and application methods (manual or with hand sprayers and fogging). |
[34, 69] |
||
| Biological control | Fish (Gambusia, etc.) | Limited entomological evidence (level 3b) for fish. | Well accepted in several countries, needs a delivery mechanism and maintenance. Adequate for treating large and/or permanent mosquito habitats, not generally accepted for drinking water storage containers. | Predators of mosquito larvae (kill all stages). Controversial, harmful impacts of nonnative species, such as Gambusia. | [34, 41, 70, 71, 72, 73, 74] | |
| Copepods (Mesocyclops) | Limited epidemiological (level 2b) and entomological evidence (level 3b) for copepods depending on settings. | Predators of mosquito larvae (kill young instar larvae). |
*Details are available in S2 Table.
Abbreviations: AGO, autocidal gravid oviposition traps; Bti, Bacillus thuriengensis serotype israliensis; DEET, N,N-diethyl-3-methylbenzamide; DT, Tablet; EC, Emulsifiable concentration; EU, European Union; GAT, gravid Aedes trap; GR, Granules; IRS, indoor residual spraying; IR3535, Ethyl butylacetylaminopropionate; ISS, indoor space sprays; ITC, insecticide-treated curtain; OP, Operational procedures; ORS, outdoor residual sprays; OSS, outdoor space spray; S, scenario; TIRS, targeted indoor residual spraying; ULV, ultra-low volume; UV, Ultraviolet; WG, Water dispersible granule; WHO, World Health Organisation.