We started to become a nation of insiders between the world wars, when public health authorities urged us to live behind screens as they sought to eliminate malaria. And then air conditioning served to draw us inside even more.
But before the advent of the Asian tiger mosquito, our main periods of summer retreat were at dawn and dusk, when native mosquitoes tend to bite. Now, the day-feeding Asian species has sort of sealed the lid. We might think of ourselves as masters of the universe, but in the human-bug equation, we are the ones in the glass jar.
As entomologists continue to seek ways to fight the Asian tiger mosquito, they warn that there is no magic bullet to make it go away. Instead we can reduce its nuisance value if we collectively adopt an approach called integrated pest management. It sounds fancy, but many of its principles are basic, such as removing flowerpots that trap water and clearing your gutters, especially in spring at the start of the breeding season.
How it got here
Like so many invasive exotics, the Asian tiger came to us by way of globalization: It was discovered in Texas in 1985 and traced to a shipment of used tires from Japan, according to a scientific paper in the Journal of Medical Entomology.
Unchecked, the species soon got a foothold in the Houston area and spread north and east, and is established today in at least 30 states and the District. It reached Northern Virginia in 1997, was found earlier in Baltimore, and now extends to the southern fringes of New York.
It is called the tiger mosquito for its stripes: white markings on its legs and body that also give it its scientific species name, Aedes albopictus. It is so unlike other mosquitoes that standard strategies to beat it back have been ineffective.
Mosquitoes lay eggs near water, and the larvae develop aquatically, pupate and fly off as adults. Many species do this in broad marshes and swamps, but the tiger mosquito evolved to grow in little pockets of rainwater trapped in tree trunks and leaf joints.
When it made its switch from the forest to the city, it found its human victims had given it an unbelievable array of breeding locations: birdbaths, empty soda cans, tires, creases in tarpaulins, plastic toys, wheelbarrows, anything that could trap water, if only for a week or two. It needs so little water to breed, it can reproduce in upturned bottle caps and the little depressions in black corrugated drainage pipes. Scientists call all these various reservoirs containers and the pest a container-mosquito.