Guard your home against the Zika mosquito

The Aedes aegypti mosquito is the worthless roommate you wish you could kill.

It never goes away. It just hangs around, mooching off you, soaking in the pool, dozing off in the corner, sucking your blood, infecting you with debilitating prospects.

The container-breeding mosquito expected to arrive here this summer carries the Zika virus, a threat to pregnant women in particular but also to the population in general: It does not cause only brain defects, researchers say. It has a range of afflictions.

And it is not the only tropical disease reaching the United States. Dengue and chikungunya are coming, too.

The Aedes aegypti mosquito is the primary vector, except in cases of Zika sexual transmission. But it is aggressive, efficient and adapted to preying on humans.

Its eggs need no more water than a plastic bottle cap, so imagine what it can do after a hard rain with all the piles of trash strewn here in the city, the discarded paper and plastic cups, bowls and to-go boxes.

Then consider what water stands outside your home, because the insect rarely roams far from where it hatched, only about 100 yards, a football field.

“They don’t go very far at all,” said Pam Kirkland of Georgia’s West Central Health District, which serves Columbus.

Other mosquitoes find furrier mammals for blood feedings, but not Aedes aegypti. It prefers humans, and it doesn’t bite just once and buzz off to lay eggs. It bites repeatedly.

One way to disrupt its life cycle is to remove any standing water around your house. But that’s easy to say, hard to do, to kill a mosquito that can breed in a thimble.

It can use any puddle, but the pregnant blood-sucking female typically lays eggs – up to a 100 or so – on the side of a bucket or flower pot or whatever has water, and though the eggs can stick there for months, surviving droughts, they typically hatch larvae into the water in a week.

The larvae develop into pupae in about five days, and in two or three days the pupae shed their skin and adult mosquitoes fly away. The males seek flower nectar. The females feed on blood.

After feeding, they may retire to a dark, quiet corner, possibly a cabinet or closet if they’re in your house, before they emerge to lay their eggs. They do not lay a single batch of eggs on just one container; they spread them around to boost the odds of hatching.

The more often they bite, the more robustly they reproduce, researchers say.

They have spread across the Southeast: Georgia, Alabama, Florida, South Carolina, Mississippi, Louisiana and Texas. Besides Zika, dengue and chikungunya, they can transmit yellow fever.

Yellow fever’s no longer a risk here, where a vaccine’s readily available, but it still plagues Africa and South America, and carries a high risk of mortality, ranging 20 to 50 percent.

Anyone who has toured a historic Southern port city cemetery knows how yellow fever once ravaged Americans who did not understand how the disease was transmitted. In the 1800s, outbreaks struck New Orleans, Mobile, Savannah and Charleston. The epidemics killed more than 100,000.

Now that Southerners understand how the disease vector works, they must be diligent to stop or at least impede its spread.

Using the catch-phrase “Tip n’ Toss,” the local health department and the Atlanta Centers for Disease Control are urging residents to inspect their homes and yards for standing water, and eliminate it.

If water must be available for pets or other animals, it should be changed once a week. Another option is to submerge a “Mosquito Dunk” in it, a disc that gradually dissolves, releasing a bacteria that kills mosquito larvae for up to 30 days, but poses no threat to fish or to animals drinking the water. Dunks are available at most home and garden stores.

Other places where water collects are obvious, such as birdbaths and wading pools. Some are not, such as tree hollows and plastic children’s toys typically left outside – the miniature cars and tricycles with depressions that collect rain.

Tarps atop firewood or other supplies will hold water, too, and should be tented so rain drains off them.

As usual during mosquito season, people are advised to wear long sleeves and long pants or insect repellent when they’re outside, and to keep their window screens and screened porches in good repair.

In the past they’ve been advised to shield themselves at dusk and dawn, when other mosquitoes feed, but the Aedes aegypti bites all day long.

More information about the mosquito, its diseases and their symptoms can be found online at these sites:

The National Centers for Disease Control, www.cdc.gov/zika.

The National Institute of Allergy and Infectious Disease, www.niaid.nih.gov.

The Georgia Department of Public Health, www.columbushealth.com.

This story was originally published April 20, 2016 at 5:04 PM with the headline "Guard your home against the Zika mosquito."