Author Archives: BioSensory

NEW ENGLAND FIRM DONATES ENVIRONMENTALLY SAFE MOSQUITO PROTECTION PRODUCT TO HURRICANE VICTIMS

Posted on by BioSensory

NEWS RELEASE

FOR IMMEDIATE RELEASE

CONTACT:  Betty Galligan, APR

Newberry PR & Marketing, Inc.

(401) 433-5965 betty@newberrypr.com

 

NEW ENGLAND FIRM DONATES ENVIRONMENTALLY SAFE MOSQUITO PROTECTION PRODUCT TO HURRICANE VICTIMS

Florida experiencing explosive  mosquito counts statewide

 

TALLAHASSEE, FL and WILLIMANTIC, CT  (October 26, 2004):  BioSensory,

Inc., a Connecticut-based technology company, has donated $10,000 worth of its

Mosquito ‘Cognito product to be distributed by the Capital Area Chapter of the American Red Cross in Tallahassee, FL to needy people throughout the state who are facing a pandemic mosquito crisis.

The American Red Cross has been serving Tallahassee and the surrounding area since 1917.  In the past eighty-three years, the American Red Cross has provided a helping hand by reaching out to local residents, and last year touched the lives of more than 10,500 people in the eight counties that it serves.  “Since the hurricanes, Florida has experienced an explosive increase in its mosquito population, including the panhandle,” states BioSensory President Jim Nolen.  “With people sleeping outside in tents and the increasing threat of West Nile Virus and EEE, we felt it was important to respond to the need for mosquito protection.”

According to Susan McKnight, BioSensory’s entomologist, “Standing water after the hurricanes have become a breeding ground for mosquitoes.  Trap counts of 80,000 mosquitoes per night have been logged from several counties – one of  which trapped 2.25 million in one night.  Normally, most counts average 100 per night so you can see that the problem is explosive.  Mosquito activity will slow as the cold fronts approach but it will not cease until Florida’s first frost which may not be until mid-November or early December.  However, the threat of West Nile is present year-round in some parts of the state.”

Mosquito ‘Cognito is a battery-operated tabletop inhibitor which uses a potent but environmentally safe substance called Conceal® to keep people and animals safe from biting insects.  The Conceal inhibitor molecule is naturally found in a number of essential oils of plants and is widely used as a food flavoring.  BioSensory’s light, compact Mosquito ‘Cognito device is a tabletop inhibitor (not a repellent) which dispenses Conceal into the atmosphere by a quiet, batterypowered fan.  A mosquito with a “nose full of Conceal” has difficulty smelling anything or anyone, so they can’t home in on their targets.

In field tests conducted by qualified entomologists from Florida to New England, the Mosquito ‘Cognito has been shown to reduce mosquito landings on humans by up to 80% when used as directed.  During the 2000 Olympics, Mosquito ‘Cognito won praise for protecting the valuable horses of the U.S. Equestrian Team during the West Nile Virus crisis.  

“Mosquitoes are attracted to carbon dioxide and Octenol, chemicals that humans and animals emit when they exhale, which can be detected from 100 feet away,” explains Mr. Nolen.  “The concept behind our Conceal technology is that it inhibits mosquitoes’ sense of smell, blocking their ability to track scent.  In U.S. Department of Agriculture laboratory tests, Conceal was twice as effective as DEET and more effective than Citronella at preventing landings.  Fewer landings mean fewer bites.” In 2003, world-renowned research entomologist Daniel L. Kline of the U.S. Department of Agriculture’s Center for Medical, Agricultural and Veterinary Entomology (Gainesville, FL) along with BioSensory’s Susan McKnight conducted comparative tests in Florida swampland and Connecticut woodland to determine the effectiveness of Conceal’s active ingredient against Citronella. Participants experienced between 26% and 64% fewer mosquito landings than those using Citronella or no/plain candles for protection.

“Our technology is quite sound and continues to be proven effective for both humans and animals,” Mr. Nolen adds.  “Conceal will soon make Citronella obsolete.”

Developed through a research and development agreement with the U.S. Department of Agriculture, the Conceal inhibitor represents a scientific breakthrough that has earned a series of patents for BioSensory, which manufactures a family of mosquito protection products for residential, commercial and abatement district applications.

# # #

Established in 1996, BioSensory, Inc. is a U.S.-based manufacturer of advanced technology products to control mosquitoes and biting insects without insecticides such as Pyrethrin or repellents containing DEET.  Patented and trademarked products include

The Dragonfly System, Mosquito ‘Cognito and Conceal Candles.  Through a Cooperative

Research and Development Agreement with the Agricultural Research Service of the United States Department of Agriculture, the company has developed, tested and distributed environmentally safe products throughout the world.  BioSensory is located in the Windham Mills Technology Center, 322 Main Street, Building 1, Willimantic, CT  06226-3149 USA.  Phone:  860.423.3009; Fax: 860.423.3028; Web: 

www.biosensory.com

 Mosquito ‘Cognito and Conceal are registered trademarks of BioSensory, Inc.

ENVIRONMENTALLY SAFE MOSQUITO PROTECTION SCIENTIFICALLY PROVEN

Posted on by BioSensory

NEWS RELEASE

FOR IMMEDIATE RELEASE

CONTACT:  Betty Galligan, APR

Newberry PR & Marketing

401.433.5965   USA betty@newberrypr.com

 

ENVIRONMENTALLY SAFE MOSQUITO PROTECTION SCIENTIFICALLY PROVEN TO

New technology now available in Canada in candle form;  a convenient alternative to sprays, foggers, traps, repellents containing DEET; helps protect against mosquitoes that may carry West Nile

WILLIMANTIC, Connecticut  USA  (August 12, 2004):  BioSensory, Inc., a U.S.based manufacturer of advanced technology products to control mosquitoes and biting insects without insecticides such as Pyrethrin or repellents containing DEET, announces its Conceal® inhibitor, available as a cartridge in BioSensory’s battery-operated Mosquito ‘Cognito® product and now as a Conceal® Candle, has been proven to Citronella superior for warding off biting insects.

 

“Mosquitoes are attracted to the carbon dioxide and Octenol, chemicals that humans and animals emit when they exhale, which can be detected from 100 feet away,” states Jim Nolen, BioSensory president.  “The concept behind our Conceal® technology is that it inhibits mosquitoes’ sense of smell, blocking their ability to track scent.  In U.S. Department of Agriculture laboratory tests, Conceal was twice as effective as DEET and more effective than Citronella at preventing landings.  Fewer landings mean fewer bites.”

BioSensory’s Conceal® is an inhibitor, not a repellent.  The inhibitor molecule is naturally found in a number of essential oils of plants and is widely used as a food flavoring.  A mosquito with a “nose full of Conceal®” has difficulty smelling anything or anyone, so they can’t home in on their targets.

In 1995, a Canadian study was conducted by L. Robbin Lindsay et. al. from the Department of Environmental Biology at the University of Guelph in Guelph, Ontario Canada.  The study was done in a deciduous woodlot in Guelph, surrounded by large snowmelt pools where large numbers of mosquitoes are found.  Human test subjects conducted biting counts using 3% citronella candles, 5% citronella incense, plain unscented candles and no candles. Lindsay concluded that the overall percent reduction in mosquito bites provided by the citronella candles was 42.3% and plain candles was 23.1%.  Given the reduction in mosquito biting activity produced by the act of burning candles, the addition of 3% citronella to candles further decreased biting activity by only 19.2%, which is not significant.

“Our technology is quite sound and continues to be proven effective for both humans and animals,” adds Mr. Nolen.  “If we can educate the masses about the  product, as we are attempting to do, Conceal® will soon make Citronella obsolete.” In 2003, world-renowned research entomologist Daniel L. Kline of the U.S. Department of Agriculture’s Center for Medical, Agricultural and Veterinary Entomology (Gainesville, FL) along with Susan McKnight, BioSensory’s entomologist, conducted comparative tests in Florida swampland and Connecticut woodland to determine the effectiveness of Conceal®’s active ingredient against Citronella. Participants experienced between 26% and 64% fewer mosquito landings than those using Citronella or no/plain candles for protection.

“The active ingredient in Conceal® is almost a miracle product, and has been proven effective in many independent field tests,” states Ms. McKnight.  “With major outbreaks of the West Nile Virus in both Canada and the U.S., mosquito abatement is at a crucial point.  Scientists are seeking viable alternatives for consumers to today’s chemicals and pesticide spraying.  Like the northern U.S., many parts of Canada are actually shallow glacial depressions which stretch for miles and have almost identical mosquito species to their U.S. counterparts although many of the insects are larger in Canada.  When the snows melt, these depressions become like pools — perfect breeding grounds for mosquitoes.  The  sheer number of mosquitoes in these areas can make the Everglades in Florida look like nothing,” she concludes.

Conceal® inhibitor is now available in a variety of attractive, fragranced candles to protect people from biting insects.  Each candle, which retails for $6.00 – $20.00

US, has an effective range of up to 100 feet and is designed for outdoor use.

# # #

Established in 1996, BioSensory, Inc. is a U.S.-based manufacturer of advanced technology products to control mosquitoes and biting insects without insecticides such as Pyrethrin or repellents containing DEET.  Patented and trademarked products include

The Dragonfly System, Mosquito ‘Cognito and Conceal Candles.  Through a Cooperative

Research and Development Agreement with the Agricultural Research Service of the United States Department of Agriculture, the company has developed, tested and distributed environmentally safe products throughout the world.  BioSensory is located in the Windham Mills Technology Center, 322 Main Street, Building 1, Willimantic, CT  06226-3149 USA.  Phone:  860.423.3009; Fax: 860.423.3028; Web:  www.biosensory.com

Scientific breakthrough thwarts mosquitoes, provides alternative to DEET and Citronella

Posted on by BioSensory

FOR IMMEDIATE RELEASE

For Further Information Contact:

Phone:  860 423-3009 x10

Email: mail@biosensory.com

Scientific breakthrough thwarts mosquitoes, provides alternative to DEET and Citronella

Conceal Candles from BioSensory, Inc. have proven to be an effective inhibitor of mosquitoes and other biting insects, offering unprecedented protection for people without the unpleasant odor and oiliness of common topical repellents like DEET and making ineffective Citronella-based products obsolete.

Conceal works when its molecules floating in the air bind to insects’ olfactory receptors, blocking their sense of smell.   Because mosquitoes have poor eyesight, they use their sense of smell to track people and animals.   When mosquitoes can’t smell people or animals, even nearby, they can’t locate and track them.   As a result, their landings will be less frequent.   Fewer landings, fewer bites!

In fact, in field tests by qualified entomologists from Florida to New England, Conceal Candles have been shown to reduce mosquito landings on humans by up to 80% when used as directed.

Conceal Candles contain a potent but environmentally-friendly substance called Conceal to keep people and animals safe from biting insects.   The Conceal inhibitor represents a scientific breakthrough that has earned a series of patents for BioSensory.

Conceal Candles disperse Conceal into the atmosphere.   You simply place the lighted candle in an area where people congregate— deck, pool, patio.  These attractive, long-burning Conceal Candles are generally priced under $20.

BioSensory manufactures a family of mosquito protection products for residential, commercial and abatement district applications.  For more information, visit www.biosensory.com or call (860) 423-3009.

Conceal Candles and Conceal are registered trademarks of BioSensory, Inc.

Clever Gadget Leads Charge Against Mosquito Brigade

Posted on by BioSensory

The Louisville Courier-Journal

Saturday, August 24, 2002
A Continuing Search for the Best of Everything
Clever Gadget Leads Charge Against Mosquito Brigade

By MARY FRANCES LANDENWICH
Who won’t be bugged

While gathering my weapons, I peer through the window at the slow setting sun, anxiously awaiting the coming of dusk. Again, I strategically plan my defense, ridding my body of any cosmetic fragrance. At last glance, the solar lanterns begin to glow like fireflies, and the purple hue descends upon my patio garden. It is time. The battle begins.

One step through the back door. I am clothed in my armor of hot, sweaty jeans and doused with the not-so-sweet smell of insect repellent, ready for the first attack. There is a brief moment of hesitation and doubt; should I have worn a long-sleeve shirt? No! No! It is my summer night, my backyard patio, and I will not be fortressed inside, held captive to so small an organism.

As the door closes, I race frantically the three yards to the Citronella torches, fumbling with the matches in the dark. The torches quickly ignite, and I sigh with relief, settling into my patio rocker, ready for the serenity of the star-filled sky to relieve the tension of the day.

I glance down at my watch. Three minutes have passed and not a bite. But I can’t relax. I know they are out there in the dark waiting to catch me off my guard. Then it happens: a faint sensation from my right foot. Looking down, I see the small, black mosquito injecting its itching poison into the top of my foot. I slap my hand down, only to miss as the quickster alights and flies from my grip. And I realize flip-flops were a mistake.

Within minutes, my anxiety rises, and I become a madwoman, suspicious of the night. To maintain my sanity, I retreat to the house to regroup.

I brood and become distant. I hate to admit defeat.

Then, alas, my trusty warrior husband, weary of my obsession to rid the yard of mosquitoes, discovers a secret weapon: the Mosquito ‘Cognito. Now I must say, although I will try anything to regain my backyard territory, I was skeptical. This green plastic gizmo with vent holes around the sides could not possibly repel these pesky insects. No smoky candles. No spray. Just pull it to open, push it to close. Too easy, I thought; too small. It must be given the ultimate test. I return to the patio at dusk, wearing shorts, a tank top, no insect repellent. I light no Citronella candles. I place the Mosquito ‘Cognito on the patio table in the “on” position, a few yards from my favorite chair. I sit and I wait. Ten minutes pass, and all is clear. Then 20, and 30. And then I knew I had won. I had regained my patio and my yard.

How does it work?
Mosquitoes can sense exhaled carbon dioxide and octenol 100 feet away. In other words, they smell you and change direction to fly toward you. The Mosquito ‘Cognito uses an inhibitor called Conceal. It is not a repellent but blocks the carbon-dioxide scent. In other words, it messes with the mosquitos’ minds, so they can’t find you. Pretty clever.

And it works. Developed under a Cooperative Research and Development Agreement with the U.S. Department of Agriculture, the Mosquito ‘Cognito runs on two AA batteries. The replaceable Conceal cartridge will last approximately 360 hours. It has a patent pending.

If you want to enjoy your back yard on a summer evening, be armed with the best and easiest product for keeping mosquitoes at bay. The Mosquito ‘Cognito can be ordered on-line at mosquitosolutions.com and costs about $30.

Go ahead; the last battle is at hand.

Mary Frances Landenwich teaches eighth-grade language arts at Highland Middle School in Louisville.

New Mosquito Control Technology Protecting Valuable Thoroughbreds

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New Mosquito Control Technology Protecting Valuable Thoroughbreds

WILLIMANTIC, CT, July 31, 2001
BioSensory, Inc, has introduced a simple yet innovative mosquito control device to dramatically reduce the number of biting and infectious mosquitoes that inflict pain and disease on valuable thoroughbred horses. Known as Mosquito ‘Cognito®, this unique technology has already proven remarkably successful at Hawthorne Hill, the New Jersey training grounds for the United States Olympic Equestrian Team (USET).

Mosquito ‘Cognito, about as big as an oversized coffee mug, takes advantage of a unique concept in the field of mosquito control. Rather than using hit and miss sprays or foggers that hope to repel insects, the ‘Cognito emits Conceal®, an inhibitor that literally blocks the mosquito’s keen sense of smell. If mosquitoes can’t track a horse’s scent, they can’t find the horse, and they move on. The active ingredient in the Mosquito ‘Cognito’s Conceal is a basic food additive found in the essential oils of plants and is approved by the U.S. Food and Drug Administration (FDA).

The “inhibitor” concept behind Mosquito ‘Cognito is simple. When horses exhale, they give off high levels of Octenol, an alcohol-based substance. Mosquitoes have sensors that are amazingly accurate in detecting the presence of Octenol, and once the scent is picked up, they will rapidly fly toward their victims. Placing a Mosquito ‘Cognito inside the entrance to any horse stable will release a level of Conceal many times more effective than conventional repellents.

When compared to traditional spraying of individual horses or the fogging of stables, Mosquito ‘Cognito has proven itself superior at numerous on-the-job test sites around the country. For example, professional trainers responsible for the valuable horses that make up our nation’s Olympic equestrian team are extremely pleased with the results.

“Given the amount of rain last summer, we would normally have had a terrible mosquito problem, with sensitive horses exhibiting numerous bites and welts,” says Michael Barisone of the USET. “Nothing we tried was nearly as effective as Mosquito ‘Cognito. Our personal experience proved that this product really works.”

Protection from West Nile

Unfortunately, some of today’s breeders are unaware of the devastating effects caused by mosquito-borne viruses, oftentimes until it’s too late. The West Nile virus, responsible for the deaths of six horses in New Jersey last year, has been spreading through the northeast and south faster than first anticipated, and scientists have been searching for viable alternatives to today’s chemicals and pesticide spraying. To encourage effective mosquito control alternatives that offer protection against West Nile, as well as Eastern and Western Equine Encephalomyelitis, research on technology like that used in Mosquito ‘Cognito has been jointly funded by both the public and private sectors.

“Mosquitoes home in on a horse’s exhaled CO2 and Octenol from as far away as 100 feet,” says BioSensory founder, Jim Nolen. “By putting Conceal into the air and literally blocking the insect’s sense of smell, Mosquito ‘Cognito dramatically reduces the chances of mosquitoes ever getting close enough to bite.”

Each ‘Cognito costs about $30.00. Its Conceal cartridge lasts 360 hours in continuous use, or about one to two months in normal operation, and the alkaline batteries used to drive its small fan last about 700 hours. To purchase Mosquito ‘Cognito and other BioSensory products, visit www.nomorebites.com. For a list of professional pest control companies that carry Mosquito Cognito, log onto www.biosensory.com.

BioSensory, Inc., is a high technology company located in Willimantic, Connecticut. Through a Cooperative Research and Development Agreement with the Agricultural Research Service of the United States Department of Agriculture, the company has developed, tested and is marketing products utilizing the most advanced technology to control mosquitoes and biting insects without pesticides or toxic repellents.

BioSensory Offers New Technology To Fight Backyard Mosquitoes

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BioSensory Offers New Technology To Fight Backyard Mosquitoes

WILLIMANTIC, CT, July 26, 2001
The days of greasy insect repellent, smoky candles and mosquitoes ruining a back yard family picnic may be gone forever. BioSensory Inc., a technology company out of Willimantic, Connecticut, has introduced Mosquito ‘Cognito®, an innovative device that effectively prevents pesky mosquitoes from landing on you and your dinner guests all summer long.

Mosquito ‘Cognito, about as big as an oversized coffee mug, takes advantage of a unique concept in mosquito control. Rather than using hit or miss sprays and oils that hope to repel insects, the ‘Cognito emits Conceal®, an inhibitor that literally blocks the mosquito’s keen sense of smell. If mosquitoes can’t track your scent, they can’t find you, and they move on. The active ingredient in the Mosquito ‘Cognito’s Conceal is a basic food additive found in the essential oils of plants and is approved by the U.S. Food and Drug Administration (FDA).

The “inhibitor” idea behind Mosquito ‘Cognito is simple. When humans exhale, they give off CO2 (carbon dioxide) and Octenol, an alcohol-based substance. Mosquitoes have sensors that are amazingly accurate in detecting the presence of these two chemicals, and once the scent is picked up, they will rapidly fly toward their victims. Placing two or three Mosquito Cognitos on a deck, patio or pool will release a level of Conceal many times more effective than conventional repellents like DEET and Citronella oil at keeping away annoying mosquitoes.

“Mosquitoes home in on a person’s exhaled CO2 and Octenol from as far away as 100 feet,” says BioSensory founder, Jim Nolen. “By putting Conceal into the air and literally blocking their sense of smell, Mosquito ‘Cognito dramatically reduces the chances of mosquitoes ever getting close enough to bite.”

With the dreaded West Nile virus spreading through the northeast and south faster than first anticipated, scientists are seeking viable alternatives to today’s chemicals and pesticide spraying. To encourage viable mosquito control options, research on technology like that used in Mosquito ‘Cognito is being jointly funded by both the public and private sectors.

Proven Effective

Mosquito ‘Cognito has already proven itself at on-the-job test sites around the country. For example, Vector Control Supervisor Mark Ritter of the St. Louis City Department of Health personally tested Mosquito ‘Cognito and found it “remarkably effective.” Trapping scores of mosquitoes over a few nights to establish a fair population benchmark, Ritter then used Cognito to determine its effect at keeping mosquitoes at bay.

“I was amazed at how successful it was,” stated Ritter. “Mosquito landings dropped by over 80%, simply by having a single Mosquito ‘Cognito sitting on the back porch. This product really works.”

Each ‘Cognito costs about $30.00. Its Conceal cartridge lasts 360 hours in continuous use, or about one to two months in normal operation, and the alkaline batteries used to drive its small fan last about 700 hours. To purchase Mosquito ‘Cognito and other BioSensory products, visit www.nomorebites.com. For a list of professional pest control companies that carry Mosquito Cognito, log onto www.biosensory.com.

BioSensory, Inc., is a high technology company located in Willimantic, Connecticut. Through a Cooperative Research and Development Agreement with the Agricultural Research Service of the United States Department of Agriculture, the company has developed, tested and is marketing products utilizing the most advanced technology to control mosquitoes and biting insects without pesticides or toxic repellents.

New Mosquito Trap in Time for Summer

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New Mosquito Trap in Time for Summer

By Tara Weaver-Missick
July 13, 1999

Mosquitoes are in for trouble this summer, thanks to a new trap that effectively attracts and kills mosquitoes and biting flies. The trap was co-developed under a Cooperative Research and Development Agreement between Agricultural Research Service and BioSensory, Inc., of Willimantic, Conn.

The trap, registered under the trade name Dragonfly, was named for the insect that is a mosquito predator. The trap lures mosquitoes with a blend of carbon dioxide, heat and octenol, the same chemical cues that attract mosquitoes and other biting insects in nature. Mosquitoes find their human and animal blood meals first by sensing carbon dioxide in breath. Mosquitoes can sense carbon dioxide up to 100 feet away. They also can find their prey using heat sensors on their antennae.

The trap mimics the human or animal blood system, which helps lure mosquitoes to the trap. The difference is that when mosquitoes hone in on the target and stop to dine, they are killed with an electronic pulse and fall into a removable tray. That’s a big advantage over traditional electrical bug-zapping type traps that splatter the insect everywhere into tiny bits.

Entomologist Daniel L. Kline, with ARS’ Mosquito and Fly Research Unit, part of the Center for Medical, Agricultural and Veterinary Entomology in Gainesville, Fla., conducted field studies showing that the trap was effective in capturing mosquitoes.

The attractants are registered with the U.S. Environmental Protection Agency for controlling mosquitoes and other biting insects. ARS and BioSensory have a joint patent on the attractants used in the trap, with one patent pending.

The trap should be commercially available this summer from BioSensory. Questions regarding the availability and costs should be directed to the company’s marketing vice president, William A. Gregoricus.

ARS is the U.S. Department of Agriculture’s chief scientific research agency.

Scientific contact: Daniel L. Kline, ARS Center for Medical, Agricultural and Veterinary Entomology, Gainesville, Fla., phone (352) 374-5933, fax (352) 374-5922, dkline@gainesville.usda.ufl.edu. William A. Gregoricus, BioSensory, Inc., Willimantic, Conn., phone (860) 423-3009, fax (860) 423-3028, biosensory.corp@snet.net

Bits, Bytes and Biological Barriers,

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“Bits, Bytes and Biological Barriers,”

Spring 1999 Volume 10, Number 1

By Jim Nolen
Jurassic Park taught everyone that mosquitoes have been around for hundreds of millions of years, so it is not surprising that they diversified into species very different from one another. After all, they have successfully adapted to climates from the artic to the equator, and everywhere they have solved fundamental survival problems. They must locate carbohydrates to fuel their flight muscles, blood to supply protein to the egg clutch, and suitable habitats in which to lay their eggs. It is also not surprising that indigenous hosts are as varied as the locale; some mosquitoes are adept at finding frogs, others birds, still others mammals. Specialized adaptations exist within and between these categories. Some mosquitoes prefer birds but are adapted to find mammals. Some are especially well programmed to find small herbivorous mammals but easily detect humans nearby.

Mosquitoes are physiologically well-equipped. They can sense electromagnetic radiation from ultra violet to infrared, detect minute changes in pressure, temperature and humidity, track their prey’s scent like a bloodhound, and they need not stop to smell the flowers as they can do it in flight. Eons of natural selection have focused their instinctive programming on that combination of sensory input that identifies locally abundant hosts, floral nectar and water for oviposition on which their survival depends. We studied three clues mosquitoes use to find a host: scent, sight, and heat. Structures on the antennae and palpae detect the scent of the host’s odor plume at a distance of up to 30 meters. The mosquito follows the plume upwind and makes visual contact at a distance of approximately 10 meters. Three meters away (farther when it is humid) thermal receptors on the tips of the antennae help locate warmer areas where blood is near the surface of the skin. Some species can detect temperature changes as small as 0.1ºC.

Tsetse Fly
Those who understand how sensory inputs affect instinctively programmed behaviors can turn the insect’s evolutionary success against them. In the 1980’s, British scientists succeeded in controlling the Tsetse fly in Africa. Tsetse is a serious health hazard. It feeds on livestock and humans, spreading sleeping sickness. The scientists analyzed ox breath using gas chromatography, and then used electroantennograms to isolate the two most powerful attractants: carbon dioxide (CO2) and octenol (1-octen-3-ol), a form of alcohol. Octenol and CO2 are kairomones, chemical components of host odor which mosquitoes can detect. Fermenting vegetation in the ox’s digestive tract produces octenol, which along with CO2 is expelled with each breath. Today, baited traps are deployed to control several species of Tsetse fly. Aerial pesticide applications stopped in 1991.

Methods the British used in Africa were straightforward, and the sensory structures of mosquitoes and biting flies are similar, so why are success stories like this rare? There are many answers to the question. Tsetse flies are an easy mark compared to mosquitoes. Their hosts were known, their host-seeking behaviors were easily deciphered and vulnerable to attack, and they are not prolific breeders. This is not the case with mosquitoes.

Mosquitoes
There are more than 3,000 species of mosquitoes with many different host-seeking behaviors. Narrow the scope to include only public health pests and hundreds of species remain. Attempt to alter their behavior with attractants, repellents or inhibitors, and the results are influenced by variables we cannot completely control: season of the year, time of day, weather and location. Each influences the behaviors being studied and makes it difficult to isolate experimental results so they can be accurately measured.

The problems are so difficult that an impossibly large number of experimental trials are required to achieve a comprehensive understanding of behavior. Consequently, experimental trials are limited to those that can be completed within the time and budget available. The experimental protocol becomes the embodiment of our priorities; we design it to reveal the knowledge we believe to be most important and postpone the rest of what we want to know.

Repetition of trials also limits what can be done in a given amount of time. Repetition is built into the experimental protocol to average the effect of environmental variables we cannot control over several trials. Repetition builds our confidence when identical trials produce similar results. Equally important, repetition tells us outside influences are at work when identical trials produce different results. Sometimes we get the results we expected. Sometimes we are left wondering how to explain the result we got.

As part of a Cooperative Research and Development Agreement (CRADA) with the United States Department of Agriculture, we demonstrated that accurate numerical predictions of mosquito collections in response to several experimental variables could be developed in as little as 15 days of field trials. Traditional application of the scientific method might take hundreds of trials and years in the field to accomplish the same result. Specifically, we generated 90% accurate models (correlation of predicted vs. actual catch) of each species’ response to any combination of four attractants. The attractants were CO2, octenol, heat, and visual targets of three different sizes.

The level of each attractant was tested over a wide range. For example, CO2 emissions ranged from zero to 1,000 ml/min, which is approximately equivalent to the respiration of four large men. Octenol ranged from zero to 28 mg/hr, which is equivalent to the emission from several cattle. The visual targets and thermal lures were combined into one device. The visual target consisted of a closed metal cylinder. Inside the metal cylinder were electrical connections for incandescent light bulbs. Because the metal cylinder trapped the light inside it, the energy of the incandescent bulbs (which radiate 10% of their energy as light and 90% as heat) was dissipated as heat through the thin, conductive skin of the cylinder. The outside of the metal cylinder was painted black to radiate energy most quickly. The inside of the metal cylinder was painted a mottled pattern of white and black to produce a non-uniform surface temperature. This effect is intended to simulate the non-uniform thermal emissions of living things. Previous research indicated non-uniform surface temperatures are more attractive than a uniform surface temperature. The size of the smallest visual target was equivalent to the trunk of the body of a small animal such as a rabbit or woodchuck. The next larger size was equivalent to the trunk of an animal such as a deer or goat. The largest size was equivalent to the trunk of a man. Finally, incandescent bulbs of various wattages were used in combination to produce three levels of thermal emissions. The lowest thermal emission was zero (no incandescent bulbs). The next higher thermal emission was 0.016 Watt/cm2 (0.1 Watt/in.2), characteristic of animals with lower body temperatures. The highest thermal emission was 0.031 Watt/cm2 (0.2 Watt/in.2), characteristic of warm-blooded mammals with higher body temperatures.

There are an infinite number of combinations of these four attractants, so how can 15 trials produce an accurate model over the whole range of variables for every species collected? The computer-designed protocol does not test every possible combination of attractants, but specifically selects the fewest combinations from which a statistically valid model may be constructed. Taylor Second Order Expansion Equations are used together with a specially selected fractional factorial design to do so.

The fractional factorial design cleverly uses results (insect collections) of midpoint replicates to minimize the number of trials required to produce a statistically sound model. Just as human researchers gain confidence from identical trials that produce similar results, so to does the computer. The midpoint of every variable is tested repeatedly and the differences in the collections determine the level of confidence we have with the result. Next, the experimental design tests each variable at its extremes, both high and low. Not every combination of high and low extremes is tested. Only trials sufficient to determine whether the effect of a given variable (or its squared value, or its interaction with another variable) is to increase or decrease collections as the variable is increased or decreased.

To validate the predictions, the trials are repeated and the actual collections compared to the predicted values. CRADA research will not be published until later this year, but two examples illustrating very different behaviors are reproduced here: Culex nigripalpus, a St. Louis encephalitis vector, and Culicoides furens, a biting midge.

Figure 1 is the model for Culicoides furens, the infamous biting midge and an aggressive pest in the Southern US and the scourge of tropical beaches. This tiny creature is particularly difficult to control. With a wingspan of 1mm, it can easily pass through physical barriers such as screens or mosquito nets. It deposits its eggs in the inter-tidal zone between the high and low water mark, minimizing their exposure to larvicides. This model indicates that Culicoides furens is strongly attracted to heat and octenol.

img-bits-figure1

The first line of information at the top of the graph contains the key used to identify the curves on the face of the graph. The face of the graph contains three curves representing the predicted catch at three levels of body heat. Low (L) represents no energy radiated as heat. The Mid-point represents 0.0155 Watt/cm2 (0.1 Watt/in.2) energy radiated as heat. High (H) represents 0.031 Watt/cm2 (0.2 Watt/in.c2) radiated as heat. As mentioned previously, the Mid-point and High curves simulate the body heat of living things.

We can graph only two values on a two-dimensional sheet of paper, so other experimental values must be held constant. The second and third line of information at the top of the graph lists the variables that were held constant. In this case, the visual target was held constant at a surface area of 4,580 cm2 (710 in.2), approximately the size of the trunk of a man. This size visual target produced the largest collections of midges. CO2emissions were held constant at 200 ml/min, equivalent to the respiration of a 90-kg (200 pound) man.

The horizontal axis is the octenol emissions, which range from 0 mg/hr to 28 mg/hr. As mentioned previously, the higher rate is characteristic of herbivorous mammals.

The vertical axis labeled ‘cf’ is the total predicted Culicoides furens collections per night using a CDC trap mounted at the CO2 discharge point 15.25 cm (6 in.) from the visual target/thermal lure. Collections took place in October 1996 at the University of Florida Medical Entomology Laboratory at Vero Beach Florida. The coefficient of correlation between predicted versus actual collections was 0.97 for this model.

Figure 2 is the model for Culex nigripalpus, the St. Louis encephalitis vector. The left portion of this model indicates that Culex nigripalpus is strongly attracted to heat and CO2, a profile characteristic of avian hosts. The right portion of this model indicates Culex nigripalpus is also strongly attracted to high levels of octenol, a host profile characteristic of animals such as cattle.

 

Timg-bits-figure2he format of Figure 2 is identical to Figure 1, with the exception that a different size visual target is used. In this case, the visual target was held constant at a surface area of 516 cm2 (80 in.2) simulating a small animal such as rabbit or woodchuck. This size visual target produced the largest collections of mosquitoes.

The vertical axis labeled ‘cn’ is the total predicted Culex nigripalpus collections per night using the CDC trap described previously. The coefficient of correlation between predicted versus actual collections was 0.98 for this model.

While the scales remain tipped strongly in favor of the mosquito, the computer speeds up the pace of progress. When the insect’s behavior is understood, a multidiscipline team of entomologists, chemists, and engineers can quickly focus on the best opportunities to exploit that behavior. For example:

  • Breaths of CO2 five seconds apart collect more mosquitoes than continuous discharge.
  • A very narrow range of temperature, 43ºC ± 8ºC, increases collections. Temperatures less than 35ºC do not increase collections. Temperatures greater than 51ºC reduce collections.
  • Irregular infrared patterns (mottled patterns of cooler and warmer areas) produce larger collections than uniform ones.
  • The visual image and thermal emission of a small animal produced the greatest mosquito collections, while the visual image and thermal emission of a larger animal produced the greatest midge collections.
  • An avian host attractant profile produced larger collections than mammalian host attractant profile for Culex nigripalpus.

    • These differences profoundly impact the way one designs traps for the poultry industry’s chickens as opposed to the tourist industry’s beach-goers.

The efficiency (target insects collected per ml of CO2, for example) of traps built to the specifications of the target species (as indicated by the combination of attractants that maximized collections) is very high. Efficient traps maximize collections, lower costs and are harmless to non-target species, making them a viable alternative to insecticides in some cases. For example, Dr. Jonathan Day of the University of Florida has created a midge-free zone 275 meters in length at Boynton Beach, Florida. He used CO2 and octenol-baited traps spaced at 12 m intervals. While the traps were running they removed flies at distances of at least 6 m in all directions.

Dr. Daniel Kline of the USDA in Gainesville, Florida reports that mud samples taken from this area contain no larva when test line is on and trapping sand flies. Health officials in the Gold Coast of Queensland, Australia are that country’s midge experts. They continue to look for alternative control measures because of insecticide resistance. They occasionally resort to malathion and beach raking to reach eggs buried 6 to 10 cm below the surface of the inter-tidal zone. Considering the difficulties of midge control, Day’s accomplishment is no small feat. It is Day’s opinion that removal trapping may serve as an alternative form of midge control at a cost competitive with present day insecticide strategies. We also are confident that biological attractants can be effective in limited but important applications. Moreover, biological inhibitors that cannot achieve control may, however, reduce pesticide use in important applications such as residential pest control, commercial pest control, and livestock protection.

Our CRADA research originally focused on gaining an understanding of the interaction effects of attractants. As our understanding of the underlying chemistry improved, we soon found ourselves concocting substances that bind more strongly to proteins on the insect’s receptors than do kairomones in the host’s scent. This approach lead to better attractants. For example, one new attractant seems to be particularly effective against Aedes aegypti. In a preliminary trial in the USDA’s 10 by 20 m outdoor cage in Gainesville, Florida, 1,000 Aedes aegypti were released and 750 were recovered. The experimental control, an efficient trap baited with 500 ml/min CO2, recovered only half as many. This approach also lead to better inhibitors. Because troublesome species of mosquito smell your scent long before they can see you, inhibiting their scent tracking ability seems to be a worthwhile strategy. One new inhibitor reduced landings on humans by 50% compared to landings in an unprotected control location, although there were large individual differences between test subjects, and some species may be less susceptible than others. In preliminary olfactometer trials with Aedes aegypti, this new inhibitor was almost twice as effective as DEET in preventing mosquitoes from locating human scent. Essentially all Aedes aegypti located human scent alone, which was the experimental control.

The technology’s promise has attracted various business partners who wish to develop applications for their markets. What does the future hold? It is early and our crystal ball is very foggy, but some of the possibilities appear below.

  • Lower cost alternatives to pyrethrin for animal protection in dairy barns, chicken coops, and other livestock enclosures.
  • New methods of releasing high levels of attractants for outdoor spatial barriers.
  • New methods of releasing tiny amounts of high-purity attractants or inhibitors for use indoors and in programmable traps.
  • Small traps for indoor use in tropical regions.
  • Alternatives to pyrethrin for indoor household use in tropical regions.
  • Inexpensive devices powered by a 9-Volt battery or solar energy surrounding breeding sites to trap mosquitoes.

Special thanks go to Dr. Jonathan Day of the University of Florida Medical Entomology Laboratory, Dr. Scott Ritchie of the Tropical Public Health Unit, Cairns, Queensland Australia, and Dr. Daniel Kline of the USDA Center for Medical, Agricultural and Veterinary Entomology for their help in the preparation of this article.