You wouldn't think of calling a mosquito "man's best friend." But that's the nickname that biologist Denise Valle uses for Aedes aegypti, the species that's been spreading the Zika virus in Brazil and many other countries in Latin America.
I think "man's best enemy" might be better.
The thing is, this mosquito likes to live near humans.
Aedes aegypti breeds in shaded wet places — so cities are an ideal habitat — and feeds on us. It's the female that bites us and uses our blood to produce eggs. And the mosquito is not just a carrier for Zika virus. It also carries dengue fever and chikungunya,
The big question: How does Brazil control its mosquito population?
Aedes aegypti is one of the most difficult mosquitoes to eradicate in Brazil, Valle says. It's very inventive about finding wet spots to lay its eggs — open barrels, buckets, holes in the ground. And the mother mosquito is a brilliant strategist.
"The Aedes aegypti likes to lay its eggs in several places, giving its offspring a better chance to survive, and those eggs can stay viable for an incredible 450 days, in a kind of suspended animation," Valle says. "And they hatch in minutes once the rains come."
Which brings us, she says to Brazil's failure so far to control the mosquito. Yes, it's hard, she says, but both the authorities and Brazilians are to blame for the situation. She says in the rainy season — roughly December through February — everyone is combating the mosquito and talking about it. Come the dry months, and everyone forgets about it. But that's the best time to get rid of the breeding grounds.
She says the mosquito needs to be constantly battled.
But the average Brazilian, in my experience, isn't out there fighting mosquito wars.
Many people don't use repellent, they don't have screens on their doors they don't have screens on their windows. I ask Valle, "Why is that?"
She tells me that's part of the culture that needs to change. She believes that the government's anti-mosquito patrols have made people passive. They think it's the responsibility of health inspectors who do home visits to 'save' them from infestations.
I ask about reports I've read in the newspaper that the government might try to kill the mosquito with nuclear radiation.
Valle shrugs. They come up with something new every summer, she says. Some people have talked about using lasers to zap mosquitoes in midflight; others talk about using genetically modified mosquitoes.
She doesn't think any of the ideas are cost effective and practical for Brazil's megacities. Her advice is simple. Think like a mosquito — and hunt it in the places where it likes to live.
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