SA¹ú¼Ê´«Ä± has partnered with PolitiFact to fact-check Florida politicians. The Pulitzer Prize-winning team seeks to present the true facts, unaffected by agenda or biases.
Even if you’re not typically averse to bugs, the idea of raising and then releasing thousands of insects into the wild might give you the heebie-jeebies.
But if it helps you rest easier, the mass release of sterile male insects is a long-standing means of insect population control, and it’s now being used to slow the spread of vector-borne diseases, including those carried by mosquitoes.
Screwworm — a harmful parasite once largely eradicated with the help of a successful sterile insect program — is . Multiple reported U.S. have drawn news coverage, as has a request from researchers with project to release millions of mosquitoes in Florida and California.
The concept raises questions: How does it work? Is it typically successful? Is it ecologically safe? Here’s what scientists want you to know.
How the sterile insect technique works
Let’s take the New World screwworm and the Aedes aegypti mosquito — two insect populations in the news.
Screwworm infestations are most common among livestock, but they can occur in humans and pets. The lay eggs in warm-blooded animals’ open wounds or orifices, including the eyes, noses and mouths. After hatching, screwworm larvae burrow into skin and eat live flesh for about five to seven days, before falling off their host and burrowing underground to mature into adult flies. Left untreated, infestations can be deadly.
Aedes aegypti mosquitoes spread infectious diseases dengue, chikungunya, yellow fever and Zika. Google’s Debug project, launched to slow mosquito-borne disease spread, 40% of people on Earth are at risk of contracting a disease spread by this species of mosquito, which is invasive . That’s in line with figures from the U.S. and the , which also hopes to reduce infectious disease spread by introducing wolbachia bacteria to weaken local mosquitoes’ ability to transmit diseases.
To thwart screwworm infestations, researchers typically raise a large group of screwworm flies and then expose the males to enough radiation to render them infertile, but not so much that it kills or hinders their ability to mate. These sterilized flies are into an area with a screwworm infestation. When wild female screwworm flies mate with the sterilized males, the resulting eggs will .
Meanwhile, Google it is testing ways to raise sterile male mosquitoes. One method includes using mosquitoes infected with wolbachia, a bacteria that prevents them from successfully breeding with wild mosquitoes. It’s different from the typical radiation sterilization, but the result is the same: Mosquitoes that can’t produce viable offspring. The result is the same as : Mosquitoes that can’t produce viable offspring. Google wants to then release millions of sterilized males so that when wild females mate with them, their eggs — just like the screwworms. The is to reduce each successive generation’s size as more sterilized males are released.
It can be difficult to raise mosquitoes in the massive quantities needed to actually decrease overall populations. They’re fragile, but Google it is developing new technology to make that easier.
READ MORE: Texas officials race to prevent spread of New World screwworm
Is this an effective way to manage harmful pests or disease-spreading insects?
History and research show that it can be.
We’ve successfully agriculture pests such as screwworm for decades using sterile insects, said Greg Simmons, a retired entomologist in the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service.
The technique , and North America is among six continents that have successfully used radiation-induced sterile insects for more than 60 years. Scientists began studying the method in the 1930s and it was first against screwworms in the late 1950s.
Sterile insects are also used to fight , a method "so significant that it is now considered the cornerstone of fruit fly suppression programs," said one published in the entomology journal Insect Science.
It has successfully helped combat disease, too. used it to suppress tsetse fly populations, which can transmit , which can kill livestock.
When it comes to mosquitoes, wolbachia-infected mosquitoes have also shown . A , for example, found that repeated releases of wolbachia-infected sterile male mosquitoes in Singapore reduced wild mosquito populations and ultimately reduced dengue risk.
Sterile mosquitoes have also been used to drive down populations in China, Singapore and Mexico, said Eric Caragata, a professor at the at the University of Florida. In the United States, the technique has been used in some , and Google is hoping to build on that.
What are the limitations of this approach?
The technique is not highly useful against all insect populations, experts said.
Researchers need to be able to rear insects at a large scale and, in some cases, separate males from females. The larger an overall insect population is, the more sterilized males will be needed to drive down the population, Caragata said.
That can be expensive, and some insects don’t thrive if they’re reared in bug factories on artificial diets or if their biology isn’t well suited to certain methods of sterilization such as being exposed to radiation.
A sterile insect release program is also unlikely to be a one-and-done solution. The insect population can recover over time, like we’re seeing now with screwworms.
If researchers are releasing more adult insects, they also don’t want to risk increasing the spread of the problem or pathogen. In that way, mosquitoes are good candidates because male mosquitoes blood feed or bite humans, which is what . Similarly, it’s the larval screwworms, not the adult flies, that pose the problem to livestock and other animals.
Screwworm and mosquito , meaning a targeted release of sterile males can have a greater impact than it might with other insects.
Releasing sterilized insects works only as part of a multi-pronged approach, Simmons said. When industry and government officials in the U.S. and Mexico were working to stop occasional screwworm infestation outbreaks in the 1970s, they used sterilized releases alongside other tactics.
Simmons described "armies" of workers educating everyone from big ranchers to people in small villages about how the screwworm could impact their cattle herd or their family’s cow.
"They would teach people about screwworm, they would treat animals with wound treatments," he said. "It wasn’t just sterile insects."
Are there ecological ramifications?
Aedes aegypti mosquitoes are invasive to Florida and California, where Google has its millions of Wolbachia mosquitoes.
"There is no clear evidence of any ecological impacts," Caragata said.
As invasive species, the aedes mosquitoes "are not naturally part of the food chain," and there’s also no evidence that any natural predators that eat mosquitoes rely on them as an exclusive food source, he said.
PolitiFact Researcher Caryn Baird contributed to this report.
Our Sources
- Interview with Greg Simmons, a retired entomologist in the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service and visiting scientist at the university of california riverside, June 8, 2026
- Email interview with Eric Caragata, an assistant professor at the University of Florida/Institute of Food and Agricultural Sciences’ Florida Medical Entomology Laboratory, June 8, 2026
- Email interview with Edwin Burgess, an assistant professor of veterinary entomology at the University of Florida/Institute of Food and Agricultural Sciences’ Department of Entomology and Nematology, June 8, 2026
- Emailed statement from Bruno Col, communications director for the World Mosquito Program, June 9, 2026
- International Atomic Energy Agency, , accessed June 5, 2026
- International Atomic Energy Agency, , published 2005
- Infectious Diseases of Poverty, , Sept. 26, 2024
- Journal of Economic Entomology, ,
- Reuters, , June 5, 2026
- The Rockefeller University, , Oct. 28, 2025
- Jackson County Vector Control District, , accessed June 8, 2026
- World Health Organization, , Sept. 26, 2024
- Iowa State’s Center for Food Security and Public Health, , January 2025
- County of Santa Clara, , accessed June 8, 2026
- Healthbeat, , Jan. 5, 2026
- The Associated Press, , June 8, 2026
- The Associated Press, , June 5, 2026
- Reuters, , June 5, 2026
- University of Missouri Extension, , accessed June 9, 2026
- PennState Extension, , Oct. 24, 2025
- Oxford, ,
- The Rockefeller University, , Feb. 19, 2021
- International Atomic Energy Agency, , 1975
- ScienceDirect, , April 2026
- International Atomic Energy Agency, , June 21, 2017
- Asian Pacific Journal of Tropical Medicine, , May 2025
- Texas A&M University, , June 11, 2025
- New England Journal of Medicine, , Feb. 11, 2026
- What Diseases Do Mosquitoes Carry? 3 Serious Illnesses to Know
- Insect Science, , Sept. 29, 2025
- The Atlantic, , June 29, 2016
- Debug, , accessed June 8, 2026
- Arizona Cotton Research and Protection Council, , accessed June 9, 2026
- U.S. Centers for Disease Control and Prevention, , accessed June 9, 2026
- World Mosquito Program, , June 9, 2026
- MIT Technology Review, , June 10, 2026
- Debug, , Oct. 6, 2016