Male mosquitoes swarm during mating and some will rest on the sides of houses. Both male and female mosquitoes will seek shade during hot weather and, if a house is shady and cool, then mosquitoes may cling to the walls. Generally, large swarms of insects clinging to a house or side of buildings are non-biting midges (see our "Insects Commonly Mistaken for Mosquitoes" section). These look very much like mosquitoes, but do not bite. They are often called "blind" mosquitoes. If midges are clinging to your house it is a good idea to wash them down with a hose to prevent them from staining your wall.

Why some people seem to be more attractive than others to mosquitoes can involve many factors. Carbon dioxide is the most universally recognized mosquito attractant and draws mosquitoes from up to 35 meters. When female mosquitoes sense carbon dioxide they usually adopt a zigzagging flight path within the plume to locate its source. Once in the general vicinity of a potential host, other cues predominate, including body odors (sweat, lactic acid, etc.) and heat. Odors produced by skin microflora also play a part in inducing the mosquito to land. Over 350 compounds have been isolated from odors produced by human skin. Either singly or in combination, many of these compounds may be attractants - and many may be repellents. Visual stimuli, such as movement, also factor into host-seeking. The ingestion of garlic, vitamin B12 and other systemics has been proven in controlled laboratory studies to have no impact on mosquito biting. Conversely, eating bananas did not attract mosquitoes as the myth suggests, though perfumes do. People drinking beer have been shown to be more attractive to mosquitoes. Limburger cheese has also been found to be attractive. Scientists have theorized that this may explain the attractancy some mosquitoes find for human feet.

When the female mosquito pierces the skin for her “blood meal”, she injects a small amount of saliva into a capillary. The saliva makes penetration of her proboscis or mouthparts easier and prevents the blood from clotting. Welts or red itchy bumps that may appear after the bite of the mosquito are actually an allergic reaction to the saliva. Some people are more allergic to mosquito saliva than others and tend to react stronger. Some people may be more allergic to specific species of mosquitoes than others, which is why you may react stronger to mosquitoes in one area than another. The swelling and itching may last from a few hours to a few days. Occasionally individuals may be highly sensitive to mosquito saliva and swell significantly, even to the point where they need medical attention. In any case, people should avoid scratching these welts as bacteria from the fingernails may be introduced into the wound and cause infection.

Mosquitoes can serve as a link in the food chain. Although no species depend completely on mosquitoes as a food source, indiscriminate predators will eat mosquito larvae and or adults if other food sources are not available. During their aquatic stage, mosquito larvae provide food for other aquatic insects such as dragonfly nymphs, beetles, and fish. Mosquito control treats larvae that are in areas not generally controlled by natural predators. Many salt marsh mosquitoes hatch in the high marsh where fish cannot get to them. By treating the areas that are not being controlled by natural predators, mosquitoes remain part of the overall food chain. As adults, both male and female mosquitoes need plant nectar for food. Mosquitoes may serve as an incidental pollinator as they collect nectar for nourishment.

All organisms have their place in nature, and mosquitoes are no exception. If mosquitoes went extinct, other species will fill the niches left by mosquitoes after an initial shuffling period of variable length. However, mosquitoes' ability to adapt to changing environments would make them all but impossible to eradicate.

Mosquitoes can serve as a link in the food chain. Although no species depend completely on mosquitoes as a food source, indiscriminate predators will eat mosquito larvae and or adults if other food sources are not available. During their aquatic stage, mosquito larvae provide food for other aquatic insects such as dragonfly nymphs, beetles, and fish. Mosquito control treats larvae that are in areas not generally controlled by natural predators. Many salt marsh mosquitoes hatch in the high marsh where fish cannot get to them. By treating the areas that are not being controlled by natural predators, mosquitoes remain part of the overall food chain. As adults, both male and female mosquitoes need plant nectar for food. Mosquitoes may serve as an incidental pollinator as they collect nectar for nourishment.

Most adult female mosquitoes live 2-3 weeks, though this can vary by species. Some over-winter in garages, culverts and attics can live as long as 6 months.

Female mosquitoes imbibe blood to mature their eggs. It serves no nourishment function, and males do not take blood meals at all. Both male and female mosquitoes feed upon plant nectars for food and energy.

When feeding to repletion, mosquitoes imbibe anywhere from 0.001 to 0.01 milliliter.

Mosquitoes have been found breeding up to 8,000 feet in the Himalayas and 2,000 feet underground in Indian mines. In general, mosquitoes that bite humans prefer to fly at heights of less than 25 feet. Asian Tiger Mosquitoes have been found breeding in treeholes over 40 feet above ground.

Smaller species found around houses commonly weigh about 2.5 milligrams. The largest species weigh in at a whopping 10 milligrams.

Some species, like the Asian Tiger Mosquito, prefer to breed around houses, have limited flight ranges of about 300 feet. Most have ranges of 1-3 miles, however, the undisputed champions are saltmarsh breeders - having been known to migrate up to 100 miles in exceptional circumstances, although 20 to 40 miles are more common when looking for a host. Mosquitoes can also be carried large distances when caught in an updraft.

Depending upon the species, mosquitoes can fly at about 1 to 1.5 miles per hour.

Dog heartworm is a very common disease of canines and to a lesser extent cats caused by a parasitic worm (Dirofilaria immitis) that can be debilitating, even fatal. It is transmitted to dogs by the bite of an infected mosquito. Adults live in the dog's heart and release microscopic young worms into the dog's blood. Human infections are sometimes discovered, usually during lung X-rays. Pet owners should talk to their veterinarians about protective medication to avoid dog heartworm. For more information: www.heartwormsociety.org

Many studies have been conducted on this issue in the United States and abroad. The experts have concluded that the insects are not capable of such transmission. Many biological reasons would lead one to this same conclusion, but the extensive experimental studies are the most powerful evidence for the conclusion.

1. HIV DOES NOT replicate in mosquitoes. Thus, mosquitoes cannot be a biological vector as they are for malaria, yellow fever, or dengue. In fact, mosquitoes digest the virus that causes AIDS.
2. There is no possibility of mechanical transmission (i.e., flying contaminated syringes); though HIV can be transmitted by dirty needles. However, the amount of "blood" on a mosquitoes' mouth parts is tiny compared to what is found on a "dirty" needle. Thus, the risk is proportionally smaller. Calculations based on the mechanical transmission of anthrax and Rift Valley fever virus, both of which produce very high titers in blood, unlike HIV, showed that it would take about 10,000,000 mosquitoes that first fed on a person with AIDS and then continued feeding on a susceptible person to get 1 transmission.
3. Mosquitoes are not flying hypodermic needles. Mosquitoes regurgitate saliva into the bite wound (the normal route for disease transmission) through a separate tube from that through which it imbibes blood.

At least 43 species of mosquitoes have been found infected with the West Nile virus in the United States. Not all of these, however, are capable of maintaining the virus in such a manner as to permit them to transmit it among organisms. Many of these infected mosquitoes feed only upon birds, thus contributing to a cycling of the virus among avian populations. Other species feed upon these infective birds and then will feed upon mammals, including humans. These are called "bridge vectors" because they serve as a conduit for the virus to travel from its reservoir in birds to its final host in humans or other mammals. In urban settings, Culex pipiens is usually the primary vector. In rural areas, particularly in the western part of the United States, Culex tarsalis is the primary transmitter. As control measures for each of these mosquitoes are considerably different, it's important to know which is known to be in your area. Contact your local mosquito abatement district or the Technical Advisor of the American Mosquito Control Association (904-215-3008) for information regarding the mosquitoes found in your area.

West Nile Virus (WNV) is transmitted by mosquitoes, and by the end of 2004 it had spread over much of the country. Most people who are infected will not experience any symptoms, or may experience flu-like symptoms (West Nile fever) and then recover. In rare cases, the virus may cause West Nile encephalitis with severe symptoms requiring hospitalization. While WNV can affect anyone, risk increases with age. People over 50 are at higher risk to develop serious symptoms.

WNV is here to stay, and our office is prepared to do surveillance for the virus and to respond in the event of an outbreak. There is still much to learn about WNV, and we are working in cooperation with agencies and research facilities across North America to find out the best way to deal with it. There is a vaccine available for horses, and we recommend that horse owners consult with their veterinarian. People can reduce their risk of infection simply by reducing their exposure to mosquito bites.

According to the Center for Disease Control,
 

• A product containing 23.8% DEET provides an average of 5 hours of protection from mosquito bites.
• A product containing 20% DEET provides almost 4 hours of protection from mosquito bites.
• A product with 6.65% DEET provides almost 2 hours of protection from mosquito bites.
• A product with 4.75% DEET provides roughly 1 and a half hour of protection from mosquito bites.

These examples represent results from only one study and are only included to provide a general idea of how such products may work. Actual protection will vary widely based on conditions such as temperature, perspiration, and water exposure.

Choose a repellent that provides protection for the amount of time that you will be outdoors. A product with a higher percentage of active ingredient is a good choice if you will be outdoors for several hours while a product with a lower concentration can be used if time outdoors will be limited. Simply re-apply repellent, following label instructions, if you are outdoors for a longer time than expected or start to be bitten by mosquitoes. Content source from http://www.cdc.gov/ncidod/dvbid/westnile/qa/insect_repellent.htm .

Many people also believe that erecting purple martin and bat houses will reduce mosquito populations. However, in-depth studies have shown that mosquitoes comprise no more than 0 to 3% of the diet of purple martins. Likewise, bats are opportunistic feeders and will eat a variety of insects. They most likely feed on whatever is most numerous and easiest to catch, and if necessary will travel far from their roosting sites in search of prey. Martins and bats will consume mosquitoes, but are not likely to significantly reduce the population. They should be protected and encouraged because they are interesting residents of the natural environment, not because of their ability to control pests. Citronella plants have also not been proven to effectively repel mosquitoes.

At least 10 studies in the past 15 years have unanimously denounced ultrasonic devices as having no repellency value whatsoever. Mate location through wing beat frequency caused a great deal of research to be conducted for ultrasound to be used as a chemical-free form of control. Yet, all attempts to affect mosquito behavior by ultrasound have fizzled, despite large amounts of money spent on research and development. Clever, high-tech, and imperceptible (by humans) use of ultrasound proved to be an effective marketing tool for repeller manufacturers. By appealing to the public’s chemophobia, homeowners were urged to buy ultrasonic repellers and the like to rid their houses of pests without the need to inhale "even one breath of poisonous spray". Unfortunately, no such miracle cure exists. A pioneering study testing five different ultrasonic devices against four mosquito species convincingly demonstrated that ultrasound in the 20-70 kHz range used by these devices had no effect on reorienting flight by female mosquitoes either toward or away from human subjects. Additional tests have shown that sound generators capable of a wide range of frequencies were also ineffective in repelling mosquitoes. The fact is that these devices just do not work - marketing claims to the contrary.

Consumer interest has been generated by the marketing of devices designed to attract, then either trap or kill, mosquitoes. Many products even claim to significantly decrease, or virtually eliminate local populations by decreasing the number of egg-laying females. All of these traps utilize some form of attractant that lures the host-seeking female mosquitoes to a capture or killing device. In some cases, mosquitoes are captured via an impellor fan that suctions them into a net, where they desiccate. Other systems use a sticky surface to which the mosquitoes adhere when they land, or electric grids to electrocute mosquitoes drawn into contact. Each requires some level of maintenance, i.e. propane tanks need replacement, capture nets need emptying, adhesive boards require replacement and grids require cleaning to ensure their continued effectiveness.

The process of a mosquito questing for a blood meal involves a complex, interconnected cascade of behaviors, each probably having its own cues, be they sight, smell, or body temperature. The complexity of these behaviors may account for the bewildering variations in trapping efficiency noted for certain species of mosquitoes at different times, seasons and places. With 174 species of mosquitoes currently recognized in the United States, this is no small issue and will require many years before research can provide a clarification. There is some anecdotal evidence that these baited traps, indeed, capture more females of some species than others, depending, to some extent, on the concentration of carbon dioxide emitted and the mosquito species. There may also be seasonal and circadian variables that affect mosquito responses to certain attractants. Nonetheless, these devices will trap and kill measurable numbers of mosquitoes. Whether this will produce a noticeable reduction in the mosquito population in each case will depend upon a number of factors, e.g. individual tolerance level, absolute mosquito population size, proximity, size and type of breeding habitat producing re-infestation, wind velocity and direction, and species of mosquito present, and others. Thus, the homeowner must still use repellents and practice source reduction methods as adjuncts to realize any measure of relief. Please be cautioned against putting too much faith in traps as your sole means of control. These traps represent an evolving technology that is a most welcome addition to our mosquito control armamentarium. Their potential is great, but shouldn't be overestimated. It's highly unlikely that these devices, whatever their improvements, will ever fully supplant organized community-wide mosquito control programs, for there is no single silver bullet that will prove to be the ultimate answer to mosquito problems.

Scheduled sprays used by these misters can needlessly broadcast pesticides into the environment, which affects mosquitoes and non-target insects alike. Modern mosquito control strategies emphasize an integrated approach, based upon a profound knowledge of the target, so that its various vulnerabilities can be exploited by the many tools we've developed for that purpose. Effective mosquito control requires continual survey of adult mosquito populations to determine if certain triggers for control are met. This reduces the use of adulticides to only those times when they are required.

Bug zappers do indeed kill some mosquitoes. However, the only two controlled studies conducted to date by independent investigators at the University of Notre Dame showed that mosquitoes comprised merely 4.1% and 6.4% respectively of the daily catch over an entire season. Even more important was the finding in both studies that there was no significant difference in the number of mosquitoes found in yards with or without bug zappers. What is particularly disturbing, however, is the number of non-pest insects that comprise the vast majority of trap catch. Many of these insects are beneficial predators on other insect pests. They in turn constitute a major part of the diet of many songbirds. Indeed, reduced numbers of moth and beetle prey species have contributed significantly to the decline of songbird populations in many affluent suburbs. Insect electrocution devices undoubtedly bear some responsibility for this phenomenon. Mosquitoes continue to be more attracted to humans than to the devices. One study conducted in homeowners' backyards showed that of the insects killed by these devices, only 0.13% were female mosquitoes. An estimated 71 billion to 350 billion beneficial insects may be killed annually in the United States by these electrocuting devices.

The number one thing a homeowner can do to prevent mosquitoes is to not give them a place to lay their eggs and develop. Mosquitoes will generally take at least 7 days to complete the life cycle of egg to adult and water is needed for this to happen. If standing water is changed or discarded at least once a week, mosquitoes will not have a chance to develop. If possible, schedule your activities to avoid the times when mosquitoes are most active - usually dawn and dusk. You should also dress in light, loose-fitting clothing. Mosquitoes are relatively weak fliers, so placing a large fan on your deck can provide a low-tech solution. Citronella candles have a mild repellent effect, but do not offer significantly more protection than other candles producing smoke.

Earlier blog entries have mentioned “LAMP” testing, but what exactly is that? So let’s shine a light on the subject! (You see what I did there?)

A major component of our operations is collecting mosquitoes (to read more about surveillance, click HERE). I have previously covered what happens to most collected mosquitoes (for a review, click HERE). Still, at TMAD, we like to go big or go home, which is why in 2018, our board of directors voted to invest in implementing our own in-house West Nile Virus testing.

We were the first mosquito control district in the state to incorporate this specific technology into our routine operations, and we are especially proud of this!

That’s nice and all, but what is it?

LAMP stands for “loop-mediated isothermal amplification.” It’s a mouthful, but the basic idea is simple: isolate and amplify genetic material to show the presence of the West Nile virus. By having this equipment and technology in our own lab, we eliminate turnaround time and can even test mosquito samples on the same day as collection. This is a big deal for public health! During peak West Nile virus season, we can essentially set out a trap, collect extra mosquitoes from that trap, and test them as soon as they are brought back to the lab. Then, instead of waiting a week or two weeks for results from the state lab, we can know the same day if we need to send out our trucks or our plane to a specific area. This allows us to be more “proactive” rather than “reactive.” 

 

 

 

 

 

 

 

The Process

LAMP testing is all about the genetic material within the cells or ribonucleic acids (RNA). Ribonucleic acids are present in living cells, and the general purpose is to carry instructions about making proteins to your cell’s DNA (deoxyribonucleic acid). Once mosquitoes are collected from a trap, this RNA must be extracted. This means that the rest of the cell needs to be essentially dissolved so that the RNA is easily isolated.

This is done by pulverizing the mosquitoes (making a mosquito milkshake!), separating the solids from the liquids by centrifuging, taking out some of the “slush” (i.e., homogenate), and then washing away the “unnecessary” parts of the cell to get the RNA by itself. 

This is the most labor-intensive part of the test and usually takes about 45 minutes to an hour, depending on how many samples are being extracted. Cells are stubborn little things!

After the extraction has taken place and the RNA is isolated, we must then amplify it to make it easily visible to the processing equipment. Finally, dyes and primers are added to enable the RNA to show up in the last step-the all-powerful Genie!

The Genie is the little machine that does all the final analysis and clearly reports positive and negative results. It usually takes about thirty minutes for this processing to complete.

 

How do you know the test was done correctly?

In every test run in our lab, we also run a positive and negative control. What does that mean? For every group of samples tested, we also run one sample that we know will be positive by adding specific reagents and one test with only water added instead of mosquito RNA to know it will be negative. If either shows anything other than the expected positive or negative result, we know that the test was possibly contaminated and will retest. This ensures that we are only working with the most accurate results better to serve the public health needs of our citizens. 

You should see four “peaks.” These represent a positive result for the presence of the West Nile virus. The dotted yellow line is a positive control, and though hard to see, a light green line flat on the X-axis represents negative control. This demonstrates that the test is not contaminated and the results are accurate.

 

How many samples can you run at once?

We can run up to 16 samples at once, including the positive and negative controls. We can do this twice a day if we need even more samples tested, for a total of 32 samples a day. We are exploring our options for increasing this number in the future.

Final thoughts

We strive to use science-based evidence to make our treatment decisions. LAMP testing is just one facet of the ongoing Integrated Mosquito Management strategy we use in our operations. Knowing where the West Nile virus is located quickly, we can better target our treatments and keep our citizens safer!

Have more questions or want to chat? Call our office, and we will be happy to help!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pesticide applications within the state of Louisiana must comply with Louisiana Pesticide Law (RS 3:201-3389) and are regulated by the Louisiana Department of Agriculture and Forestry.

After the USEPA determines an insecticide can be registered for use in the United States, the Louisiana Department of Agriculture & Forestry (LDAF) determines which pesticides can be registered and applied in the State of Louisiana. The primary aerial adulticide material used by Tangipahoa Mosquito Abatement is Naled.For more information about Naled and other pesticides, visit: http://www.lsuagcenter.com/nr/rdonlyres/bb1ca7e1-deac-42f4-9fbe-ec5d3a7c4b22/84892/38mosquitolarvaeprofessionalapplicators2012.pdf

The number of phone calls does not determine when or where treatment for adult mosquitoes will be done. Spraying for adult mosquito outbreaks occur only on an as needed basis. TMAD conducts several on-going types of surveillance to quantify mosquito populations. In general, staff are aware of mosquito population increases. Occasionally, phone calls are important because they alert the District of potential problem areas that surveillance has not predicted. It could also indicate an individual is experiencing a problem specifically in their property or neighborhood. In these situations, an inspector will be contacted to check for mosquitoes.

It is against State regulations to spray for mosquitoes without scientific data to show treatment for adult mosquitoes is justified. If TMAD is notified of the location, date, and time the event is to be held, at least 3 working days in advance of the event, various methods of surveillance can be done in that area to determine if treatment can be justified. Please call 985-543-0454 to request treatment for a special event.

Spraying for adult mosquito outbreaks occurs on an as needed basis. This need is based on weather, mosquito populations, and virus activity. TMAD conducts several ongoing types of surveillance to quantify mosquito populations.

Our larval surveillance and control season approximately starts in March and runs until roughly mid November (depending on weather). The District hires two seasonal workers in addition to our seasonal night drivers. These employees work from March until October/November. There are 10 regular full-time employees who spend the “off season” training, updating and digitizing section maps, compiling and analyzing data, maintaining equipment, conducting educational programs for area students, planning for the next season, and exploring ways to improve the program.

No, our control materials do not affect horse or deer flies, and there is currently no wide-scale economical and environmentally sound way to control ticks. There are repellants for humans that may be effective on horse and deer flies, and your veterinarian or farm supply store can recommend repellants for animals. Repellants, wearing light-colored clothing, and avoiding their habitat are the best way for people to avoid ticks.

Neither. We are a special taxing district funded by property taxes collected entirely within our service area. Our governing body is a Board of Commissioners. See http://www.tangimosquito.org/BOCMeetings.asp for the meeting schedule.

Yes, you can say no. We can also provide a variety of special responses for citizens. For example, we may be able to establish a buffer around a residence where someone has an allergy to aerosols, or we can notify them before we use the aircraft near their property. If you have questions or concerns, call the Main Office at 985-543-0454.

Our control materials and formulations are designed for use by professional applicators and are quite expensive. Bti is available in various forms at home and garden or farm supply stores.

Warm temperatures and heavy rain during a short time period, generally means more mosquitoes. If rainfall is spread over a wide area, it makes it more difficult for all areas to be reached with our larval control before the larvae become adult mosquitoes. Sometimes closely spaced rains will produce more than one brood (or hatch) of mosquitoes in the water at the same time. Consequently, some sites will have to be treated twice, and we may not have enough time and resources to do this. Conversely, normal rainfall or a dry period generally means fewer mosquitoes, and populations are easier to control.

In general, the answer is no. Our two larvicides, Bti and methoprene, pose no danger to people, pets, or wildlife, even if they drink the water. Of course, for extra safety, children and animals should be kept clear while we are making a treatment. People may be concerned that because we are killing mosquito larvae and adults, we might be depriving wildlife such as ducks and bats of their food. Animals such as ducks and bats do not rely on a single source of food, and will frequently switch diets during the year as different foods become plentiful.

As for adult mosquito spraying, the pyrethroids used by TMAD pose no measurable health risk to humans and animals, but are toxic to fish and bees. Therefore, we do not spray near water or blooming crops. Permethrin is only applied to dense vegetation where mosquitoes rest during the day, and resmethrin is applied as a fog during the evening when mosquitoes are active but bees are not. All of our materials are registered for use in Louisiana and are among the safest available. As professional applicators, we take pride in only making a treatment when necessary, following label directions, and minimizing the potential impacts on non-target species. We live in this area and enjoy the outdoors too, so we take a personal as well as professional interest in protecting the environment.

The extremely small droplet aerosols used in adult mosquito control are designed to target adult mosquitoes that are in flight at the time of the application. These small droplets degrade rapidly, and leave little to no residue on the impacted area at ground level. Very low application rates for these products, generally less than 4 grams of active ingredient per acre, are instrumental in minimizing adverse impacts as well.

Organized mosquito control agencies often go to extraordinary lengths to accommodate individuals who, for varying reasons, prefer their property not be sprayed with approved public health insecticides. When surveys indicate the need for adult sprays, they are approved, planned and conducted with special regard to the concerns of chemically sensitive persons. Personal notification of chemically-sensitive individuals of spray times in addition to using Global Positioning Systems (GPS)/Global Information Systems (GIS) technology to reduce the likelihood of drift over unauthorized areas are but a few of the means utilized to ensure mosquito control serves the entire public spectrum. Should you desire that your property not be sprayed, please notify your local district.

The Environmental Protection Agency (EPA) has regulated mosquito control through enforcement of standards instituted by the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) since its inception. This legislation mandated documentation of extensive testing for public health insecticides according to EPA guidelines prior to their registration and use. These data requirements are among the most stringent in the federal government and are met through research by established scientists in federal, state and private institutions. This process costs a registrant several million dollars per product, but ensures that the public health insecticides available for mosquito control do not represent health or environmental risks when used as directed. Indeed, the five or six adulticides currently available are the selected survivors of literally hundreds of products developed for these uses over the years. The dosages at which these products are legally dispensed are at least 100-fold less than the point at which public health and environmental safety merit consideration. In point of fact, literature posted on the websites of the EPA Office of Pesticide Programs, Centers for Disease Control and Prevention (CDC), American Association of Pesticide Safety Educators and National Pesticide Information Center emphasizes that proper use of mosquitocides by established mosquito control agencies does not put the general public or the environment at unreasonable risk from runoff, leaching or drift when used according to label specifications. (For the federal government's position on risks associated with mosquito control insecticides, visit http://www.epa.gov/pesticides).

The safety profiles of public health insecticides are undergoing increasing scrutiny because of concerns with how the specialized application technology and product selection protect the exposed public and environment. In fact, well over 200 peer-reviewed scientific studies in various national and international refereed journals since 1980 have documented the safety and efficacy of these public health insecticides at label rates in addition to their application techniques.

There are a number of possibilities here:

• Your street is in a zone which was not scheduled to be sprayed, but near enough to a zone which was scheduled for spraying
• You may have heard one of our trucks with the spray engine running (but not actually spraying) driving to their assigned spray area.
• The driver may have determined that your street could not have been safely sprayed. Possible reasons that could have caused this decision are:
  • too many people outdoors (both on the street and in their yards)
  • parked vehicles or other obstacles along the street or blocking the turnaround which would interfere with the ability of our driver to safely navigate the area
  Note: If the driver does determine that they could not safely spray an area, they are required to make a notation on their spray sheet as to the location and why they could not spray.
• The driver may have inadvertently missed your street when it should have been sprayed. This does happen from time to time, and we do want to know when it happens so that it can be brought to the driver's attention.

The District has been subdivided into 19 distinct areas that we call “zones”. During the active mosquito season, about 5 of these zones will be sprayed on a typical night. Weather permitting, this allows for the entire district to be sprayed weekly. This can allow for a limited number of zones with especially high numbers of mosquitoes (or mosquito- borne virus activity) to be sprayed twice within a week.

The following map shows which zones have been scheduled to be sprayed that evening: http://www.tangipahoa.leateamapps.com/PublicMap.php

Once a driver reaches his/her spray zone, the spray motor on the back of the truck stays running the entire time he is traveling. So some of the time the driver could just be moving from one street to the other and not actually spraying. However, when the driver is spraying the top lights should be engaged and a fine mist can seen coming from the sprayer.

Once spraying begins, our targeted spray speed is 15mph, although drivers can effectively spray between 5-20 mph. This range is possible because the trucks are equipped with computerized variable flow metering systems. These systems increase or decrease flow rates based on the speed of travel, assuring the proper amount of spray is being dispensed. These new systems have greatly increased the efficiency of the operation, assuring proper application, as well as saving time and money.

The main method TMAD uses to look for the presence of possible diseases in our district is mosquito pooling. This is the process of collecting adult mosquitoes to be identified, separated and tested. TMAD uses CDC and gravid traps to attract and collect adult female mosquitoes. The mosquitoes from each trap are separated by species and samples are then sent to a lab for testing. Currently, the lab tests for West Nile virus (WNV), Eastern Equine Encephalitis (EEE) and St. Louis Encephalitis (SLE).

We prioritize our limited resources to reach the areas with the greatest mosquito population density or disease activity first. If you want specific information about what’s being done around your property, call the Main Office at 985-543-0454.

District #1 consists mainly of the southern end of Tangipahoa Parish. It includes everything from the Livingston Parish line south of Highway 442 to Highway 40 to the St. Tammany Parish line. It does not include the city limits of Tickfaw. If you are unsure as to whether you are in the District, just give us a call and we will be happy to find out for you.

This map should be useful in determining whether you live within the District boundaries. View on Google Maps.