Of all the crises triggered by America's property crash, the economists never predicted a plague of blood-sucking mosquitoes — spawned in the stagnant swimming pools of unsold or abandoned luxury homes.

The phenomenon is threatening to turn into a disaster for cities such as Las Vegas, where land values in some areas tripled every year during the boom, prompting developers to build thousands of million-dollar mansions, complete with lavishly proportioned swimming pools and outdoor Jacuzzis.

Unsurprisingly, no one gave much thought to what would happen if most of the sparkling desert oases were left to stagnate in the desert heat — a result of owners either defaulting on their superjumbo mortgages, or developers being unable to get rid of their inventory amid the global credit crunch that has brought America's lending industry almost to a halt.

Now, the very developments where upwardly-mobile homeowners once splashed around under clear blue skies are quickly turning into the world's unlikeliest swampland — and an ideal place for mosquitoes to lay their eggs.

In the comfort of a solar-heated swimming pool, mosquito eggs can hatch into larvae (known as wrigglers) in about 48 hours, and become adults — able to travel as far as 20 miles from their breeding site — within a fortnight.

The phenomenon has been reported not only in Nevada, where one in every 146 homes is facing foreclosure (when a bank seizes a property to help to settle an unpaid loan), but also in Arizona and California.

Tim Gormady, a resident of Mountain Shadows Estates in Las Vegas, is one of thousands of homeowners who have suddenly found themselves living in America's post-crunch swampland, with the pool in his neighbour's abandoned house turning from blue to green.

“I truly believe that in a couple of weeks this city is going to be full of mosquitoes,” he told the Las Vegas Review Journal, adding that when one property became infested, entire neighbourhoods could be lost: “For the people who are left here, it's a bummer.”

Public health officials are already on high alert. Through their bites, mosquitoes can transmit malaria and West Nile virus - along with yellow fever and the parasitic filariasis worm, which causes the disfiguring condition elephantiasis.

Although fewer than 200 deaths are caused each year in the United States by mosquito-carried diseases, officials fear that this summer could bring a dramatic rise in the numbers unless emergency measures are taken.

Every stagnant swimming pool can spawn as many as 30,000 wrigglers. In Las Vegas, emergency crews from the city's neighbourhood response division are touring foreclosure-hit housing developments and throwing mosquito-eating fish — such as the common goldfish — into abandoned pools and Jacuzzis.

They are also using an oil-based larvicide that stops the wrigglers from being able to suck oxygen from the surface of the water.

In extreme cases, they simply pump the pools dry. “We've had crews out pumping pools every day this week,” said Devin Smith, the manager of the neighbourhood response division. “Two years ago we may have pumped six pools in a season. We're probably pumping that a week.”

But in a city that is struggling to cope with the severe economic slowdown, it is not clear who will pay for the clean-up. The city is putting liens on mosquitoinfested homes, but many of the properties are already subject to foreclosure — so only a fraction of the cost can be recovered.

Property bugs

— The Mandarin Oriental hotel in Knightsbridge, London, faced a multimillion-dollar compensation claim in 2007 after an American lawyer and his wife were bitten hundreds of times by bed bugs during a five-night stay

— Luxury mansions in Gauteng, Johannesburg, were infested by three varieties of rat in 2006

— Residents in a luxury apartment complex in Jersey City, US, were plagued by cockroaches living in an empty apartment this month

— The Upper East Side of New York suffered a bed-bug infestation in 2007. A council official wanted to ban sales of reconditioned mattresses

(Sources: www.upi.com; Times Archives)

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