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West Nile virus

Good luck avoiding mosquitoes

You can’t stop them, you can only hope to contain them.

Living in an area with so many mosquitoes means local officials can’t just ignore them, right? Harris County tries to lower the number of bugs both by spraying and introducing natural predators. The county can’t eradicate them entirely, but it can try to control bugs that have tested positive for diseases like the West Nile virus.

In Harris County, the mosquito problem peaks during the late summer months.

“It spikes up August and September, when it’s high time for hurricane weather that may trigger mosquito breeding to occur,” said Eddie Miranda, a Harris County Public Health spokesman.

Public health trucks rumble through the streets, spraying low-dose pesticides like pyrethrin and malathion to poison mosquitoes. It doesn’t hurt humans to the same degree, although people sensitive to pesticides should go indoors when crews come around. Crews spray one or twice a week in some parts of Midtown, downtown and the Northside.

The county has an app (iOSAndroid) that lets residents enter a ZIP code and find out where spraying is planned. It also includes a digital form to request mosquito breeding site inspection.

There are also other new, natural strategies from county teams to eliminate the pests, such as introducing carnivorous plants and predator bugs to chew them up. Which is good, considering a recent study found a species of mosquitoes found in the South are laying eggs that are better able to survive winter months.

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The New York Times’s Wirecutter has good options for mosquito repellants that aren’t meant to be applied to flesh. Top among their recommendations are Thermacell products, which release a scent-free vapor into the air and rids the immediate vicinity of mosquitoes.

You can spray and kill clouds of mosquitoes in your yard with pyrethrins spray, which targets the nervous system, but it won’t do much for repelling bugs. Citronella candles are also bunk — researchers have disproven the myth that the smell turns mosquitoes off.

Eliminate any still water that’s been outside your home for more than two days. Harris County Public Health recommends replacing the water in your pet’s bowls and birdbaths frequently to avoid mosquito larvae. Check flower pots, open barrels and toys as well.

Bugs need a cozy hiding place such as leaves clogging storm drains. The county recommends sweeping up the first signs of autumn to keep larvae from having a place to feed.

The story has more info about staying skeeter-free – wear long sleeves and long pants, always a delightful prospect in the Houston summer, and slather yourself with DEET – but do mind thosen prevention steps. The big guns around here include high tech traps, dragonflies and damselflies, and mutant mosquitoes. We’re playing the long game, y’all.

The mosquitopocalypse is coming

It just keeps getting better and better.

Harvey’s rain may have left Houston behind, but there’s another storm headed our way. It’s a cloud of mosquitoes, which breed in standing water and soon will be hatching by the millions.

“It’s going to be horrible in two or three weeks,” said Cory Barcomb, operations manager for Mosquito Squad, a Houston mosquito control service. He’s bracing for the onslaught, bringing in heavy-duty insecticide sprayers from Austin that can cover a whole neighborhood in a couple of hours.

You know all that standing water we have right now? Mosquitoes are laying eggs in it right now – as many as 500 eggs at a time. In a week or two, all those eggs will start to hatch. And before long, we’ll see a mosquito boom that will have us swatting and scratching for weeks.

“There’s no way around them,” said Dr. Mustapha Debboun, director of Harris County Public Health’s mosquito and vector control division. “Once they find water, they’re going to lay eggs.”

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Our local mosquitoes could be carrying five different viruses, according to Debboun: West Nile, St. Louis encephalitis, dengue, chikungunya and Zika.

That’s why Harris County Public Health will be studying the mosquito population to figure out where they’re the most concentrated, then strategically spraying insecticide to get rid of them.

Mosquito Control staffers will head out across Harris County soon after this new round of mosquitoes has hatched, Debboun said. They’ll do what’s called a “landing count,” which involves a brave Mosquito Control technician standing still for one minute and counting the number of mosquitoes that land on him. If it’s five to 10, there’s not a problem. If it’s 100 or more, Debboun said, “that’s a situation.”

Oh my God, there is no amount of money you could pay me to do that job. Those people are damn heroes. There will be insecticide sprayed from trucks and possibly planes to combat the buzzing menace, and we didn’t all scratch ourselves to death following other large flood events, so maybe we’ll survive this time, too. Cover yourself in DEET and empty any standing water you have on your property in the meantime. God help us all.

Let’s use mutant mosquitoes to fight Zika

What could possibly go wrong?

The Bayou City’s teeming mosquito population spawns in dark, wet nooks and carries a slew of deadly tropical diseases that could ravage the region.

So Houston is pondering a sneak attack, something akin to a Trojan Horse. Harris County officials are negotiating with a British biotech company, Oxitec, to create and release mutant mosquitoes genetically engineered so that after they’re set loose in the wild, offspring die, and the mosquito population dwindles.

Deric Nimmo, principal scientist at Oxitec, said it is a paradigm shift – “the release of mosquitoes to control mosquitoes.”

If an agreement is finalized, Harris County could become one of the first locations in the United States to use the mosquitoes, going far beyond the chemicals and public-awareness campaigns the county has long relied upon.

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Oxitec spun off from Oxford University 15 years ago to commercialize proprietary strains of insects, namely mosquitoes. The hope is that they can help reduce populations of Aedes aegypti mosquitoes, which carry the Zika virus, dengue fever and chikungunya, among other deadly illnesses. The mosquitoes are common in the Houston region.

Oxitec inserts a “self-limiting gene” into a male mosquito and releases several into the environment. Those mosquitoes then mate with females – Oxitec claims their special males out-compete normal males – and the resulting offspring die before they become adults. Over time, the overall population of the Aedes mosquito declines.

Male mosquitoes do not bite and can’t spread disease.

The company has conducted field trials in Brazil, Panama and the Cayman Islands and says it has reduced the Aedes mosquito populations by up to 90 percent in each location.

“It looks like we’re going to do or plan to do some sort of trial initially to test out the system,” Nimmo said.

Oxitec has yet to try out its technology in the U.S.

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According to the FDA, if Oxitec wanted to conduct a field trial in Harris County, the company would have to submit an environmental assessment to the agency.

Another complication: Regulatory authority over Oxitec’s mosquitoes would then likely shift to the Environmental Protection Agency.

Mustapha Debboun, director of the Harris County Mosquito Control Division, said working with Oxitec could provide another tool in the fight against Zika and other mosquito-borne illnesses.

“We’re not abandoning the tried-and-true” approaches, said Harris County Precinct 4 Commissioner Jack Cagle, who has been leading the efforts. “We’re willing to see – What can we add to the tried-and-true that can make this better, especially considering that the tried-and-true has some flaws?”

Unseasonably warm weather has prompted the division to boost staff during winter months. It has seven investigators now, compared to four, and two additional public education staffers, Debboun said.

In August, officials nearly doubled the number of Aedes mosquito traps across the county to 134. Harris County also continues to partner with Microsoft to develop high-tech traps that will sense and nab only certain species of mosquitoes, like those that carry Zika or dengue, and eventually hopes to utilize drones to find and target hot spots.

After receiving a federal grant, the county hopes by May to start research on whether mosquitoes in the region that could carry Zika are developing resistance to certain pesticides. The county also will use that money to test more mosquitoes for Zika, Debboun said.

“The crucial part of all this is to find out if the mosquito has the virus in it,” he said.

Yes, remember the Microsoft Mosquito Drone story? Nice to hear about it again, even if there isn’t much to report yet. As far as Oxitec goes, their approach is one I’ve heard about as a possible way to limit the growth of the A. aegypti population and the many diseases it helps propagate. Maybe it will work without serious unanticipated side effects, but we would be the US pioneers for such a test. I’m not sure how I feel about that, but as the consequences of doing too little are West Nile and Zika, I’m not sure how wishy washy one can be about this. What do you think?

It’s what comes after the rain that’ll get you

All that rain we got was great and badly needed to finally kill off last year’s drought. But we know what comes next.

Culex skeeter, West Nile carrier

In the last three weeks, Harris County has confirmed three cases of this potentially deadly disease in humans. Meanwhile, officials are finding the virus in more and more birds, and infected mosquitoes are spreading quickly, despite preventive spraying. The number of Harris County ZIP codes where mosquitoes tested positive for West Nile skyrocketed from six in early June to 71 as of Tuesday.

While the number of cases of West Nile in humans is just average so far this year, Harris County’s mosquito control director Dr. Rudy Bueno is concerned by an unusual spike in bird deaths from the same virus. The birds had been strategically placed in storm sewers around the county.

“We’re finding more dead birds, in particular blue jays,” he said. “They’re the sentinels. Once they start to die, it’s a red flag. That means the virus activity is pretty high.”

Bird deaths recently were recorded in six Harris County ZIP codes: 77040, 77055, 77065, 77345, 77449 and 77493.

When this virus, which originated in the West Nile valley of Uganda, was introduced into this area about 10 years ago, it killed many birds that had not yet built up immunities. But since then, Bueno said, bird deaths have been declining.

“Yet this year, the numbers are increasing again,” Bueno said. West Nile initially infects birds, which then are bitten by mosquitoes that in turn infect humans.

You can go to http://hcphes.org/mc to see where mosquitoes with West Nile virus have been found. No matter how much the county sprays, remember that the varmints you see most likely came from your own back yard. Look around for any standing water and take whatever action you can to drain it. Every little bit helps.

There are also bigger concerns.

One resident recently encountered a 5-foot, 6-inch alligator in her garage, across from Woodland Park near White Oak Bayou.

Fred Ruiz, Harris County captain for Texas Parks and Wildlife, said the alligators have been spotted more frequently this year in residential neighborhoods because of the rain.

He said the Seabrook area – where a dog was killed by an alligator estimated at 12 feet in late June – has experienced a lot of gator activity.

“They end up in the craziest places,” Ruiz said.

“Especially when it rains, the bayou becomes like a highway for gators,” he said. “They will wander into garages, anywhere that is cool.”

Game wardens trapped the Heights gator last Wednesday and released it into its natural habitat.

One presumes that was someplace other than the Heights. Keep your eyes open, that’s all I’m saying.