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[00:00:02] Welcome back to this edition of the pest geek podcast. I am your host Frank Hernandez and we’re going to be discussing Aedes mosquitoes particularly Aedes aegypti mosquitoes and why they are so difficult to control. Now the word mosquito is formed from two words in the Spanish language mosca meaning fly and Ito the diminutive of small meaning small so actually the word mosquito comes and the term means a little fly.
Aedes Mosquito Biology
Now we’re gonna go and get into some insect biology here and discussing this. And one of the things we’re going to be discussing is the order that they’re in and they belong to the order. What is known as taxonomy in the animal kingdom and it belongs to the order of diptera. Now diptera means a two winged fly. So that’s where most real flies belong to. It comes from two Greek words di meaning two and a pteron meaning wings so diptera means a two winged fly. Now it becomes it b also belongs to the super order of what is known as Culicoidea the a which where we get mosquitoes and midges belong to the same family and there are a couple of other midges in there that that belong to that family or that super order but that they belong together and they belong to the family of Culicidae a which is the mosquito. Coming from the Latin word culex meaning gnat. So that’s how we get that the term mosquito and the taxonomy of where they belong. Now the idea Aedes genus has more than nine hundred and fifty species of mosquitoes in it.
Most Common Aedes Mosquitoes The Aedes aegypti and the Aedes albopictus
[00:02:01] We’re only familiar with really two or three of them. The Aedes aegypti and the Aedes albopictus because these are the ones that do the biting and transmit the majority of the diseases or viruses they’re vectors of different viruses. All right so in the United States the Aedes aegypti is found in about twenty three states right now including the southeastern U.S. on the East Coast from New York all the way to Indiana and Kentucky. So Texas and the southern part here in Florida. It is a major mosquito problem. You know they also been found you know like I said in west all the way west to Indiana. Now how can they survive in cold environments. Well that’s the reason why they’re so difficult to control because Aedes mosquitoes the eggs can stay dormant in the south up to up to six to eight months after there is no rain and in cold weather and then all of a sudden we get a rain. And these eggs hatch and this is what people don’t understand that just because it’s cool and it’s not raining does not mean that we don’t have Aedes aegypti mosquitoes and you overly you know have the over wintering of the mosquitoes in the Northeast where you get the snow.
But in the southern part of the United States we can have them all year round and they’re just unless if the temperatures drop really low where there are the eggs don’t incubate. That’s a different matter but in most of the country where this mosquito is alive it the eggs are very resistant to drought and all of the sudden they laid the eggs and it didn’t rain or there is no water in the containers where they laid those eggs and all of the sudden the sprinklers come on because you turned them on two weeks later and the eggs hatch or all of a sudden it hasn’t rained for a month and it rains and the eggs will hatch and this is why it’s such a difficult mosquito to control because unless you are applying some type of biological control product or insecticide especially biological or insect growth regulators on a continual basis you won’t get control of the eggs.
[00:04:26] And the problem that we have with insect growth regulators in the open environment is that none of them will last more than two weeks. If you read the label some of these will say they’ll control fleas and ticks indoors up to six to seven months and they’ll control German roaches up to seven months indoors. But once they’re the photo stability if you read the label and it says it’s photo stable for only up to two weeks. So if there’s light outside unless you use them in a granular form which is a slow release form and whether it’s actually sitting water you’re not going to get up to 28 days. So if you’ve got a mosquito program where you’re canceling it in the summer in the winter months and you’re in the south you’re still going to have the mosquitoes breeding.
Getting The Maximum Mosquito Control For Our Clients
[00:05:18] And this is why we prefer to do our mosquito control from maximum control for our clients every two weeks because we just don’t we can control the the adult mosquito when they land on the plants with micro encapsulated insecticides for 14 to 28 days. You’re not going to get 30 to 90 days on that kind of product on average. It just depends on which part of the country you’re at. Remember we’re in a subtropical environment here in South Florida where we’re the only subtropical environment in the entire country. We are we’re unique ecosystem here in South Florida compared to the rest of the country. So what we experience here most people will not experience in the rest of the country and this is why large national companies have programs that really don’t work well down here because they come with the same mentality that you’re treating in the north or in the north you know the North East or the west part of the country of the central part of the country which is totally different. So a little bit of biology here on on on the mosquito the Aedes mosquito has for life stages egg larvae pupa and adult. That is the complete lifecycle of an of an Aedes mosquito. OK. Now it takes about seven to ten days from egg development into adults. So it’s very quick. We’re talking seven to 10 days. I mean the entire lifecycle of the mosquito can take you know up to two months maximum.
[00:06:58] But on average it’s gonna be two to four weeks the lifespan in an adult mosquito is two to four weeks and after a blood meal and an adult female can produce an average of between one hundred and two hundred eggs.
[00:07:14] Now she doesn’t lay them all usually in the same site but she can she can divide it among different sites but she that’s how many she’s gonna do. Now she can produce up to five batches of these eggs if she can get five blood meals during this lifespan. And you know Aedes Aegypti typically only bite people but Aedes albopictus will bite people and animals.
[00:07:40] So Aedes albopictus can live in wooded areas where there’s animals rodents you know deer pets that can attack your pets. And so it’s it’s a different insect and they have a little different behavior where Aedes Aegypti primarily prefers to be in areas where there’s people because they need to bite people. OK now both of them can bite they’ll they’ll take their food from Nectar of plants or from the juices of plants by sucking it out. Now the male only does the nectar juices of plants and the female only does blood. But both both can do both the nectar and the juices of of plants to survive and what they’re excreting OK is the the liquid that is basically the sugar that they can get from the nectar. And this is why ATSB attractant toxic sugar baits are very effective at controlling both Aedes Egypt type and Aedes albopictus populations because both of them will sit on plants and suck the nectar out of them.
[00:08:49] And if you’re using an ATSB with a toxic sugar bait that kills the mosquito you will get a almost a natural a mosquito control. OK. Now in one female and I understand this that one female is gonna lay between 500 or 1000 eggs in her lifetime in just two to four weeks. So that is an enormous amount of population. This is why a lot of the people who do vector or do city control have a very difficult time because they can’t spray as often as needed to control the problem and what I tell my clients is listen the reality is if you want mosquito control you’re going to have to pay for it either on a bi weekly basis to get optimal control because then all of a sudden in two weeks that there is no IGR there there’s no insect growth regulator whether you’re using a juvenile hormone mimic or whether you’re using a Chitin synthesis inhibitor they’re both going to last about the same amount of time by two weeks outside and then you might get a longer residual on the adults with residual control insecticides like you know micro encapsulated pyrethroids. Okay so this is where the balance is that what’s going to work in one home for one client isn’t going to work in another. OK. Because the dynamics of that neighborhood is different. If you’ve got a lot of trees with holes mosquitoes if you get all a a big rain shower. They can lay those eggs inside that tree trunk and basically hatch in there.
[00:10:37] And if you can’t spray that area well how are you going to transmit it. Now certain pyriproxyfen it will transfer to certain areas if the mosquito will land and then transferred to other bodies of water. OK but it’s not so without some other pyrethroids or I mean with some other insect growth regulator some IGR. All right. And like I said before you know you got standing water pots gutters are a big problem.
[00:11:04] People do not clean out their gutters and they’re wanting mosquito control with out cleaning out the gutters. And you have leaves in there that are moist and the larvae can live there and they can hatch and live and reproduce right there. They don’t need always standing water. This is why Aedes can adapt to pretty much anywhere and multiply and become such a big problem when it comes to transmitting diseases because they carry or they transmit so many diseases. They’re a vector of about five or six diseases now. OK. So you know the the all of the sudden like I said you don’t have you have bromiliads you have plants that hold water. You have holes and stubs you have gutters. You have a neighbor that doesn’t clean his gutters. A neighbor that leaves a birdbath without being treated. And what happens is that mosquitoes don’t fly more than 100 to 300 feet from where they’re born. So you might not even have the mosquito problem on your property the mosquito problem is actually on your neighbors property and he’s breeding them and they’re flying over but you can’t control the breeding and you really can only get you can really only get adult control.
[00:12:46] And that’s very limited because you’re at a disadvantage at a one to one hundred ratio with the breeding and you’re so you’re only killing one adult and you still have 100 being born. You’re right you’re at a disadvantage all the time. So this is why it’s important to get a survey of pretty much the entire block when you’re doing mosquito control for a client and evaluate you’ve got storm drains that are not being treated by the city and they’re you know across the street you’re going to get mosquitoes. I mean I got people who have mailboxes that have little planters at the bottom. They don’t have any plants. And the water is being laid there and the mosquitoes are breeding right. You know in the mailbox because they have this decorative mailbox. So you really have to look at all these dynamics when you’re looking at mosquito control to get effective control for your client and the client has to understand that just because they’re spraying if they’re neglecting and leaving water outside they have lots of plants outside in the garden and they having watering those trees those all need to get treated.
Diseases of Aedes aegypti Mosquitoes
[00:13:54] Okay. So what are what are we looking at with diseases now. Well the thing is that mosquitoes especially aedes aegypti and aedes albopictus mosquitoes are what are known as transmitter of what are known as Flavivirus. And what a Flavivirus of viruses is is a genus of a single strand RNA a virus in the family you know of Flaviviridae which is the the the the the the the way the bacteria is of the bacteria grows the virus. So you’ve got you’ve got Aedes aegypti which is now a transmitter. Originally of known as the yellow fever mosquito which was that was discovered in Cuba back in the 20s and the turn of the century nineteen hundred by nineteen twenty one. Well the reed commission went into Cuba and actually was able to discover that it was the aedes aegypti mosquito wasn’t known as it was known as a culex mosquito back then it’s now known as a. Now we know it’s the aedes Aegypti mosquito was the original transmitter of yellow fever. And what we know about that is that it also transmits dengue a chikungunya and it transmits Zika virus. So it is a very dangerous mosquito because it transmits so many diseases a species of Aedes out known as the Asian tiger mosquito. We also have the Aedes cinereus Aedes vexans which is the inland flood water mosquito.
Sanitation eliminating of water sources is the most natural mosquito control.
So there are many types of aedes mosquitoes that have a lot of problems but aedes aegypti is the big big concern getting into a little bit of the control sanitation is the number one thing what they discovered in Cuba and in Panama when when they did the Panama Canal is hey sanitation eliminating of water sources is going to be the number one control.
[00:15:54] This is the most natural control you want natural mosquito control get rid of the water sources get rid of those dirty gutters get rid of the bromiliad plants get rid of the plants outside that are having you know the bases which you’re having a little tray is full of water all the time you know get rid of the bird baths or if you’re gonna have a bird bath clean it out every couple of days so that the larvae can grow in there. So you need to hose it out or you know put something in there to clean it or be treating it on a regular basis.
Modern Mosquito Control Products
One of the new novel products that came into the market was the In2care mosquito trap which I’ve been following the development of this trap for several years now especially in places like Malaysia the Philippines you know in different countries where they’ve been doing what are known as as Ovi traps and positioning traps and doing the study with different hormones with different analogs with different like pyriproxyfen and with beauveria bassiana strain gha. And I was wondering when they were going to develop it and bring in here to do it and it finally is here.
[00:17:07] So this is something that I’ve been watching for a very long time and it’s not new to us. It is just a new novel. It’s new to us. It’s not a new concept it’s been probably being done for 20 years the testing on this type of and it’s proven to be very effective overseas because it’s very low cost to do. Unfortunately here in the US it’s a very high cost product. Mosquito control realistically for the average homeowner is a luxury item. It’s I want to enjoy my backyard I want to be able to grow my you know to grill my steaks at six o’clock in the afternoon when I want to. And when does the time when does know an hour before an hour after mosquitoes are there so it’s it’s basically a lifestyle product. Mosquito control it really isn’t a vector disease problem in the U.S. like it is in Africa. You know like it is in the Philippines like it is in Malaysia where you know hundreds of thousands of people are dying around the world millions a year because of the mosquito diseases. Sure we get freaked out every once in a while here because we got a scare like the Zika and then all of the sudden everybody’s back to normal again. Nobody’s paying attention to draining their sources. Nobody’s covering up everybody goes back to life as normal.
[00:18:30] But this new product called In2care mosquito trap which is pyriproxyfen and beauveria bassiana strain gha and Brewer’s yeast and what it does is it makes it attractive so that the mosquito wants to be there. The Brewers Yeast creates carbon dioxide and the mosquito wants to go there and wants to breed and then the pyriproxyfen kills the larvae and the eggs and then also it transfer when the mosquito lands on the water with his legs it’s got a little you know a little mesh that the mosquito can land on to lay its eggs in the water comfortably and then it becomes in contact with it and then it can transfer it over to another site it has a high concentration like 75 pyriproxyfen and very high more than what we normally use it at a 1 percent solution when we spread this thing is like 70 percent I believe in there and beauveria bassiana strain gha which is a bacteria that kills and grows on the mosquito adult to kill it. And what’s interesting about beauveria bassiana we’ve been using this strain for a decade in an ornamental care for the control of white flies aphids mealy bugs all the kind of pests we know it as a Mycotrol and the other the other product that we use for the control is geez I lost my train of thought.
[00:19:57] Now but we’ve been spraying in landscapes and in nurseries forever. It’s been available. I was having discussions about this product back in 2007 2008 with the manufacturer bio works and about being able to use it. The problem is there was no label for it to be used in residential environments. We do have it now interestingly enough beauveria bassiana strain gha is the same thing that is used now to control bedbugs. It is a new product to to control bedbugs and we can control bedbugs. Now with the same strain it’s just you can’t use the same label as the product using landscapes but it will control mosquitoes. Also though the problem when you when you spray beauveria are you using any biologicals like bacillus were known as BTI or you’re using Spinosad that these products don’t last long in the environment they’re designed for spray and kill. In other words whatever is there it’s gonna kill right there and then it’s going to last one or two days. The advantage is it doesn’t. It doesn’t kill or interfere with most other insects because it’s very specific. It’s very host specific. Okay. So that’s the advantage it doesn’t affect us as humans. It doesn’t affect fruits. So it is used in a lot of fruit production for that reason. All right. So attractant sugar baits are another way to use it together with In2care because if you’re spraying for mosquitoes and you have these mosquito traps you can contaminate them.
[00:21:37] That’s a big concern. And the in2care trap only deals with Aedes mosquitoes aedes albopictus aedes aegypti. It does not deal with culex. It does not deal with Anopheles mosquitoes. OK. So that’s one of the things that you have to know it is very specific because it got a an emergency registration because of the Zika problem in the U.S. It got an emergency registration which allows us to use the trap without being federally registered at that time. And this is one of the reasons why you have to take that class to use In2care before you can use it and this is why it’s not available to the public. OK so that’s not to mention they are expensive. OK. They’re ranging anywhere between 15 to twenty five dollars a trap to purchase plus about seven dollars for the for the the little sachets with come with all the tools inside and and it comes with the replacement band and everything that you have to do. You know it’s a labor intensive product that you have to put it in. You have to change it out. You know you’re talking seven dollars and you’ve got to buy a at a minimum of one hundred now. There’s only one supplier that is selling it in the U.S. and that is Univar initially Univar was only selling it in one hundred pieces.
[00:22:55] Now they’re breaking the pallet. And I think they’re selling them anywhere between 10 to 25 units at a time. But still it’s a big investment and it is an expensive product. It is a luxury ticket item and the way I tell my customers and I’m blunt and I’m saying listen this is a luxury ticket item you’re going to buy it because you want it. When people walk into a Bentleys or a Mercedes dealership they’re not there to haggle a five hundred dollar deal. They’re there because they want the car and they’re gonna buy it. And this is for customers who understand who are educated who understand the ecology. Who doesn’t want to harm the ecology who are willing to pay. It’s kind of the same people who are willing to pay for prius you know to get 50 miles to a gallon and they’re willing to pay the price that a Prius costs. You’re buying you know an electric car you know because you can afford it. And that’s the reality I don’t mince the words because we don’t have to convince people to buy this they are going to can afford it. They want it and they’re willing to pay for it or they’re not. And they can’t do it. And there’s just no way around it for us because the prices are fixed by the manufacturers. So we can’t do anything about it we can’t negotiate those prices we’re not going to get any brakes on when we’re dealing with juvenile hormones as S-Methoprene is one that is good like Altosid which comes in the granular sort of your spreading and in water areas that are standing water that one will give you up to 28 days a control in the granular form not in the liquid Novaluron which is a chitin synthesys inhibitor is also insect growth regulator.
[00:24:25] If you’re not using insect growth regulators when you’re doing mosquito control you’re really not going to get effective larval control because even a product like bifenthrin can get larva control but only up to seven days. OK. So the studies show that it’s only seven days use of micro encapsulated pyrethroids like Deltametrhin lambda-Cyhalothrin beta-Cyfluthrin Esfenvalerate those are products that you can use that are micro encapsulated you want to use a micro encapsulated product because that’s what’s gonna give you the most residual outside from photo degradation remember photo degradation is your biggest degradation and leaf and foilage and surface you know control because the sun breaks it down so quickly also by adding to the mix PBO if you add PBO which is a product like exponent which is a synergize or it’s going to double the effectiveness almost of your micro encapsulated products. Okay. And then if you add a surfactant to that a sticker sprayer then you’re gonna get a much better adhesion.
[00:25:45] So this is why mosquito control to do it right is very expensive because you’ve got to use you know three to four products to get the longest residual for your client that you could possibly get. So one guy just goes in and says I’m just using bifenthrin for everything because it’s cheap and my customers won’t pay. Well then you can’t really get them the control they want you can’t have it both ways in this world with these with product because. Understood. I understand scuse me. That the only product that you ever sell to a client that is biological is plant care and insect control. Everything in the house is dead. The paint is dead. The walls are dead. The wood is dead. The only thing that’s alive is the plants and the insects and diseases on those plants and biological things have minds of their own. You have to control them based on their lifecycle their back their habit their biology not the customer’s ability are willing to pay. That is never the determination on how you get control and this is why so many people when they go to large brands or they go to large franchises they get disappointed because they only have one product that 80 percent of the market is willing to buy.
[00:27:12] But unfortunately it doesn’t work for everybody so the 20 percent that are left are left with us specialists that know how to deal with all this and can customize a program for our clients. That gets them the control they want if they are willing and able to pay for it because that is how complicated it is dealing with all these issues and unless you have this training unless you have this information you’re you’re being told to go spray something without knowing if you’re ever going to your it’s a shot in the dark you don’t know. So I hope this has helped you understanding why especially aedes mosquitoes especially Aedes aegypti mosquito is such a big problem and it’s such difficult to control and why diseases can outbreak so quickly because of the habit of this mosquito. This has been frank the pest geek. Wishing you a pestasecular day.