GENEVA - U.N. agencies say early next year, several countries will begin testing a nuclear technique that sterilizes male mosquitoes to control the spread of dengue, Zika and chikungunya to humans. Guidance for testing countries has been developed by the Special Program for Research and Training in Tropical Diseases, the International Atomic Energy Agency, the Food and Agriculture Organization and the World Health Organization.

The World Health Organization says diseases transmitted by mosquitoes account for 17 percent of all infectious diseases globally. It says every year, more than 700,000 people die from diseases such as malaria, dengue, Zika, chikungunya and yellow fever.

Health Officials: More Birth Defects in US Areas With Zika The mosquito-born Zika virus may be responsible for an increase in birth defects in U.S. states and territories even in women who had no lab evidence of Zika exposure during pregnancy, U.S. health officials said on Thursday. Areas in which the mosquito-borne virus has been circulating, including Puerto Rico, southern Florida and part of south Texas, saw a 21 percent rise in birth defects strongly linked with Zika in the last half of 2016 compared with the first half of that year, the U.S.

The WHO says dengue has increased dramatically in recent years due to factors such as environmental changes, urban sprawl, and transportation and travel, putting half the world's population at risk of catching the diseases.

Jeremy Bouver is a medical entomologist at the joint Food and Agriculture Organization and International Atomic Energy Agency. He says a novel technique that uses radiation to sterilize male mosquitoes offers new opportunities for controlling disease. He describes the Sterile Insect Technique as a form of insect birth control.

"You release sterile males that will out compete the wild males in the field and they will induce sterility in the females so that their eggs will not hatch," Bouver said. "And, so, you will control the next generation. And, if you do that for a long time enough, you will be able to reduce and even, in some cases, eliminate the target population."

Why Mosquitos Bite Some But Not Others British researchers may have unlocked the secret of why mosquitos find some people attractive, and leave others alone. "What we found is that mosquitos have a keen sense of smell and when they find a smell they like, they attack," says James Logan at the Centre for Sustainable Pest and Disease Management in Harpenden, England.Only a handful of the nearly 400 chemical excreted by the body attract the pests.

The technique was developed in the late 1950s by the U.S. Department of Agriculture and has been successfully used to control insect pests from attacking crops and livestock, such as the Mediterranean fruit fly.

A pilot program that will start early next year will be the first time the Sterile Insect Technique will be tested targeting human diseases. The countries where the trials will take place will be announced next year, although a few likely candidates reportedly include the United States, France and Brazil.