Study summary
Electronic mosquito repellents for preventing mosquito bites and malaria infection
Enayati AA, Hemingway J, Garner P
Read the original paper- Study type
- Meta Analysis
- Year
- 2007
- Published in
- Cochrane Database of Systematic Reviews (2007), Issue 2, Art. No. CD005434
- Evidence strength
- Definitive evidence
Summary
This is the most authoritative look at electronic mosquito repellers, the plug-in and battery devices that emit a high-frequency sound meant to keep mosquitoes away. Rather than run a single experiment, the Cochrane reviewers gathered every field study they could find that measured whether these ultrasonic devices actually stop mosquitoes from landing on and biting people, and pooled what those studies showed. The category rests on the idea that a sound can drive off biting mosquitoes, and this review set out to test that idea against the accumulated field evidence.
Key findings
Across ten field studies, electronic mosquito repellents had no effect on the number of mosquitoes that landed on the volunteers being tested. The reviewers found no basis for the claim that these devices keep mosquitoes away, and concluded plainly that they have no place in mosquito-bite or malaria prevention and that further studies of the current devices are not warranted. In practical terms, for someone deciding whether an ultrasonic plug-in or wearable is worth buying, this is the clearest possible answer from the research: the sound does not reduce your bites.
Limitations
The review covers the ultrasonic and electronic devices available at the time and the field studies conducted on them, so it is a judgment on that technology rather than proof that no sound could ever affect any insect. The underlying studies varied in setting and in which mosquito species were present, which is normal for field work. None of that changes the bottom line, since the pooled result across all ten studies pointed the same way: no measurable protection.