What’s the best strategy to tackle disease-carrying mosquitoes? More mosquitoes, apparently! That’s the idea from scientists involved in Google’s Debug project. They’re planning to release 16 million mosquitoes in Florida and California as a starting point, with intentions to do it again next year.
At first glance, increasing the mosquito population seems counterintuitive. However, if you dig into the specifics, it becomes clearer what the researchers aim to achieve: they want to introduce “good” mosquitoes to combat the “bad” ones.
Google’s mosquito initiative
The plan involves raising sterile male mosquitoes and releasing them into the wild. According to the Debug website, when a wild female pairs with a sterile male, her eggs won’t hatch. This approach could gradually reduce the population over generations.
These male mosquitoes will be infected with a bacteria called Wolbachia, rendering them sterile. The idea is twofold: the next generation should diminish, as the females’ eggs won’t be fertilized, and since male mosquitoes don’t bite, there’ll be fewer instances of bites to humans.
“Mosquitoes typically mate only once in their lives,” noted Robert Hancock, an expert in mosquito behavior at the Metropolitan State University of Denver. This single mating event is central to the success of the project.
If a female mosquito chooses to mate with one of Google’s Wolbachia-infused males, any eggs she lays won’t hatch. One female can produce over 100 eggs, so the method could prevent substantial numbers of mosquitoes from being born.
Approval needed from US authorities
Separating male and female mosquitoes is quite the challenge. Thus, Debug researchers are developing technologies that utilize sensors and algorithms to effectively distinguish between males and females.
And, of course, releasing millions of mosquitoes isn’t as simple as it sounds. Debug has applied for a permit from the US Environmental Protection Agency, with a verdict still pending.
Targeting the Aedes aegypti mosquito
The Debug initiative specifically targets the Aedes aegypti mosquito, an invasive species that has its roots in Africa. This mosquito is notorious for transmitting diseases like dengue, yellow fever, Zika, and chikungunya, which is characterized by severe joint pain lasting, in some cases, for years.
Debug claims that around 40% of the global population is at risk from diseases carried by this mosquito, which has spread to various regions around the world due to changing climates.
Florida presents a suitable testing ground for such programs. “In Florida, we have some of the longest-established populations of Aedes aegypti,” explained Matthew DeGennaro from Florida International University. “There’s also a level of insecticide resistance here.”
Insects can build resistance to insecticides, similar to how bacteria in humans can become resistant to antibiotics when overprescribed.
Aedes aegypti: a problematic species
Aedes aegypti is often termed “a very bad mosquito,” according to Nathan Burkett-Cadena, an associate professor at the University of Florida’s Medical Entomology Laboratory. Being non-native to Florida, this mosquito lacks natural predators in the area.
Burkett-Cadena added that if Google were to target native species, there could be unwelcome environmental repercussions. But since Aedes aegypti isn’t native, that concern may not apply.
World Mosquito Program
The World Mosquito Program, run by Australia’s Monash University, is another initiative fighting disease-spreading mosquitoes globally. They also release mosquitoes infected with the Wolbachia bacteria across 15 countries in Asia, Oceania, and the Americas.
The program’s studies indicate that Wolbachia is passed down through generations, effectively reducing disease-carrying mosquito populations over time. Crucially, in areas with significant levels of Wolbachia, no dengue outbreaks have occurred.
So, there does appear to be a feasible way to shrink Aedes aegypti numbers. But it raises ethical questions. Do we, as humans, have the right to interfere with nature in such a drastic manner? Should we diminish populations, even of pests, simply because we have the ability to do so? Some entomologists argue in favor.
“I ‘love’ mosquitoes,” Burkett-Cadena stated. “Most species pose no threat to humans and can be quite beautiful. However, invasive species threaten human life, necessitating action from those responsible for public health.”
Biologist DeGennaro concurs. “Aedes aegypti is a species we’ve helped spread,” he said. “They follow humans around the globe, like the cockroaches or rats of the mosquito world. If the conditions are right and humans are present, you’ll find them. We have a duty to manage their populations.”
