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Oxitec

Mutant mosquito update

Keeping you informed on the news you can really use.

Four years ago, the Zika virus became an issue. More than 300 people were infected in Texas. Zika can cause birth defects and fetal neurodevelopmental abnormalities in pregnant women.

The vector is Aedes (rhymes with ladies) aegypti and Aedes albopictus mosquitoes. The Aedes mosquitoes transmit Zika, chikungunya, dengue and yellow fever, which prompted state and county health officials to discuss actionable solutions to control the mosquito.

Talks about releasing genetically modified mosquitoes in Houston began in 2018 between Harris County and Oxitec, a United Kingdom-based company that produces sustainable technologies or transgenic methodologies to stem the impact of disease-spreading insects. Talk also began about a similar action in Monroe County, Fla.

However, ecological concerns have been raised about the use of these mosquitoes.

“We had stakeholders there who wanted to use it,” said Kevin Gorman, head of field operations at Oxitec. “We had vector control authorities who were keen to try the technology.”

The Environmental Protection Agency stated in a May 2020 press release that it approved an experimental use permit to Oxitec to field-test its genetically engineered mosquito in the United States.

The genetically modified Aedes aegypti mosquitoes are males that mate with wild female Aedes aegypti, essentially causing the offspring to die before they can reproduce due to a genetic variation.

Oxitec had two successful years of controlling the Aedes aegypti in Brazil with its current generation of mosquito and had several years of efficacy in Brazil with its first-generation, Gorman said.

[…]

A release in Florida seems imminent, but not in Texas. Despite an established relationship and much communication, it looks like the Florida Keys will be going solo.

“Although we really enjoyed a sort of really great relationship with Houston at the moment we’re in a holding pattern with Houston,” Gorman said. “And we’re unlikely to be releasing there, and there certainly aren’t firm plans to do so in the next year.”

He cited uncertainty due to personnel changes in the county government as the reason for the decision.

A statement sent to Reform Austin by Sam Bissett, a communications specialist with Harris County Public Health, said the choice to not move forward with the release was made last year by both parties.

“At this time, there are no agreements or approval in place for Harris County to work with Oxitec in 2021. While we have had discussions with Oxitec previously about a potential partnership with Harris County Public Health, those discussions were paused last year between both sides.”

See here for my previous post on Oxitec and mutant mosquitoes, from 2017. There’s a lot more to the story and it’s hard to just capture the essence of it, so go read the whole thing. Apparently, the Aedes aegypti mosquito is more abundant in the Rio Grnade Valley than in Harris County, so maybe we’re not the best place to test this out in the US. Harris County also employs mosquito traps and dragonfly armies to control the local skeeter population. Which all seems a whole lot more quaint these days, but Zike and its ilk haven’t gone away just because we’re mostly inside these days. We will be spending more time outside again, and when we do we’d like to not be at significant risk from some other emergent deadly disease, thank you very much. Maybe next time we’ll be able to work something out.

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.

[…]

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.

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.

[…]

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.

[…]

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?