April 23 (HealthDay News) -- Electronic mosquito repellants -- handheld devices that emit a high-frequency buzz to repel the blood suckers -- don't stop bites and don't prevent malaria, says a review of 10 studies conducted in North America, Russia and Africa.

"EMRs should not be manufactured, advertised or used for mosquito bite and malaria prevention, as they do not do so," lead author A. Ali Enayati, a lecturer in medical entomology at the Mazandaran University School of Medical Sciences in Iran, said in a prepared statement.

All the studies he reviewed were field-based research -- they took place in natural settings instead of in laboratories. The studies all "found that there was no difference in the number of mosquitoes that landed on the bare body parts of the human subjects with or without an EMR," Enayati said.

EMRs are purported to provide users with a mosquito-free radius of about 2.5 meters (8 feet). The devices pose a health risk, because people may use them to prevent malaria, which is transmitted to humans by mosquitoes, and not use proven mosquito repellants or protection such as bed nets, Enayati said.

The review is published in the latest issue of the The Cochrane Library journal.

"I agree with the Cochrane report. There is no evidence that electronic devices prevent malaria, and many other available options should be used," Dr. Joel Breman, a senior scientific advisor at the Fogarty International Center of the U.S. National Institutes of Health, said in a prepared statement.