Frequently Asked Questions about Mosquito Control

Mosquito Biology

Are mosquitoes attracted to some people more than others?
Why do mosquitoes bite?
How many kinds of mosquitoes are there?
What purposes do mosquitoes serve?

Health and Disease

What diseases do mosquitoes carry?
Do mosquitoes carry AIDS?
What is Saint Louis encephalitis?
How does one know if encephalitis is currently being transmitted by mosquitoes?
How can children be protected from encephalitis?
Are chickens infected with encephalitis dangerous to people?
Do any of the chemicals cause cancer?
How will the spray effect people or pets if it is inhaled or if it lands on the skin?
How soon after spraying can children go outside.
What are the symptoms of organohosphate insecticide poisoning?
What can mosquito control programs do for people who are chemically sensitive or just do not want to be sprayed?
Will DEET hurt children?
Why do mosquitoes leave welts on the skin when they bite?
Why do people seem to react more to some mosquito bites than to other?

Other Control Measures

What can people do to reduce mosquitoes?
What are some alternatives to pesticides for mosquito control?
How effective are Citrosa plants?
How effective are bug zappers?
What is the best personal repellent?
What can be done when tons of mosquitoes are clinging to the house?
Is there something, which can be used to stop mosquitoes from mating instead of using pesticide?

Environment

How can one type of insect be controlled without harming other insects or wildlife?
What methods are used to kill mosquitoes and are they environmentally safe?
Is spray dangerous to butterflies?
Does the spray used by mosquito control programs kill good insects and birds?

Mosquito Control Operations

What is the best way to control mosquitoes?
What are the requirements for spraying adult mosquitoes?
What criteria are used when deciding where to spray?
How often do mosquito control programs spray for mosquitoes?
Do mosquito control programs spray for things other than mosquitoes”?
How effective is the spray?
Why can’t mosquito control programs spray during the day?
Can mosquito control programs spray ahead of time for special events, sporting events, garden weddings, parties, etc.?
Do mosquito control programs spray over the beach?
How long do the chemicals last once they have been sprayed?
How can citizens find out when spraying will occur on Panama City Beach?
Why do mosquito control helicopters fly around but not spray?
Why can’t the spray be seen coming out like before?
Who over sees pesticide applications?

FAQs answers on mosquito control

Mosquito Biology

1. Are mosquitoes attracted to some people more than others?
Yes. Mosquito attraction to humans is a very complex matter.  Primarily, mosquitoes are attracted to the carbon dioxide (CO²) emitted from the breath and pores of humans. In addition to (CO²), some species of mosquitoes are attracted to certain fragrances and colors. During mosquito season it is recommended that people who wish to be less attractive to mosquitoes wear unscented products (hair spray, soap, deodorant, etc.) and light colored clothing. Another way to become less attractive to human biting mosquitoes is to wear commercially available, proven mosquito repellents.  The most common proven repellent is DEET (N, N-diethy-meta-toluamide). There are many unproven products commercially available as mosquito repellents. No matter what repellent is used, the entire label should be read thoroughly.back

2.  Why do mosquitoes bite?
Only female mosquitoes bite or take a “blood meal.” The blood is necessary for the development of her eggs. Typically, both male and female mosquitoes feed on plant nectar. The plant sugars provide energy for the mosquito. After the make mates with the female mosquito, eggs will begin to grow in her abdomen. For most species of mosquito, it is crucial that she take a “blood meal” from an animal. The protein from the blood causes the eggs to develop properly.back

3.   How many kinds of mosquitoes are there?
Throughout the world there are over 3,000 species of mosquito species from 12 different genera, 30 of which occur throughout the entire state. There are about 25 mosquito species in this county.  Each type of mosquito has a common name and a scientific name, which includes a genus, and a species name. For instance, the Asian tiger mosquito is the common name, while Aedes albopictus is the species name. Aedes albopictus is a container-breeding mosquito and is found in all 67 Florida counties.  It is responsible for many citizen complaints.back

4.   What purposes do mosquitoes serve?
All species of plants and animals have their place in nature. Mosquitoes are no exception. They are an important link in the food chain. Many animals depend on them as a source of food. During their aquatic stage, mosquito larvae provide food for other aquatic insects such as, dragonfly nymphs and beetles, fish, frogs and water-dwelling animals. As adults, mosquitoes are eaten by birds, bats, spiders, lizards and other insects. Mosquitoes do not feed on blood alone. The blood meal is taken by the female to produce eggs. Both make and females need liquid nourishment for food.  Plants provide the source of liquid nourishment.
Mosquitoes do feed on nectar, honeydew, fruit juices and liquids oozing from injured plants.  Because this need for nourishment, mosquitoes are important pollinators of wildflowers during this feeding process.back      

Health and Disease

1. What diseases do mosquitoes carry?
Mosquitoes kill more than one million people each year with the deadly diseases they transmit.  These diseases include malaria, filariasis, dengue fever, yellow fever and encephalitis (mostly St. Louis and eastern equine). Mosquitoes can also vector (transmit) dog heartworm.  It is important to note that not all mosquitoes carry diseases. Each of the diseases is transmitted by only a few species of mosquito.

Malaria is a single-celled parasite that is transmitted by the bite of an infected Anopheles mosquito.  An infected person fells tired, has muscle pain, headaches and loss of appetite, much like the onset of flu symptoms. This is followed by chills and high fever, which usually reoccur every few days. Lab tests are required to confirm malaria infection.

Yellow fever, (so named because the infected person turns yellow from jaundice) is caused by a virus that is carried by an infected mosquito.

Encephalitis is difficult to determine because laboratory confirmation is required, a costly and time consuming procedure.  Mosquito control surveillance programs gather data from wild birds and sentinel chicken flocks to determine because laboratory confirmation is required, a costly and time consuming procedure. Mosquito control surveillance programs gather data from wild birds and sentinel chicken flocks to determine the presence of encephalitis antibodies.  Prevention and control of encephalitis has historically been addressed by local mosquito control programs.

Dog heartworm is caused by juvenile worms (called microfilariae) leaving the mosquito’s proboscis and being deposited on the skin of a dog while the mosquito is taking a blood meal. These microfilariae find the puncture would made by the mosquito and crawl into the dog’s bloodstream. Heartworm is a serious problem, which can lead to death for the dogs in Florida. However, veterinarians can prescribe medication to prevent heartworm.back

2. Do mosquitoes carry AIDS?
No evidence to support that likelihood exists. If HIV infected blood is taken by a mosquito the virus is digested (killed) inside of the body of mosquito. If a mosquito takes a partial HIV infected blood meal from a person and then immediately feeds on an uninfected person, there would not be enough HIV particles present to transmit the disease.  In fact, it is highly unlikely (1 in 10million chance) there would even be a single unit of HIV present. Finally, for a mosquito to be able to carry AIDS, the disease would need to pass from the gut of the mosquito to the salivary glands where it would later be injected into the next host. This is quite a long and extensive process even No with diseases that flourish in mosquitoes (like encephalitis).back

3. What is Saint Louis encephalitis?
Saint Louis encephalitis, or SLE, is a mosquito-transmitted viral disease. It was first recognized in St. Louis, Missouri, in 1933. Epidemics occur sporadically throughout the United States. During an epidemic, several hundred people may become ill, sometimes fatally. Symptoms of SLE are similar to other viral infections and may include high fever, nausea, severe headaches and tiredness.  The severity of the symptoms varies from person to person. They range from no symptoms at all to mild flu-like systems to severe flu-like symptoms and even death.  Only 1 in 200 people who become infected with SLE virus will develop disease. The likelihood of developing SLE symptoms is generally higher for older people.

Only a few species of mosquito in a particular area are generally capable to transmitting SLE. Mosquitoes pick up the virus in the blood of wild birds, which are carrying the disease. The birds are usually not sick themselves. The virus incubates in the mosquito’s body and eventually migrates to the mosquito’s salivary glands. This process takes about two weeks. So, if a particular type of mosquito bites a SLE-infected animal and two weeks later bites a person, SLE transmission may occur and that person may or may not to on to develop encephalitis.  In Florida, the species of mosquito that is most often responsible for SLE transmission is Culex nigripalpus, which breeds in many sites.back

4. How does one know if encephalitis is currently being transmitted by mosquitoes?
Local mosquitoes control programs and laboratories throughout the state have developed several monitoring techniques to determine the presence of Saint Louis and eastern encephalitis
The mosquitoes, which carry encephalitis primarily, feed on birds.  One method of monitoring these viruses is by using caged chickens strategically located throughout the country. A small blood sample from each chicken is taken periodically and tested for antibodies to Saint Louis or eastern encephalitis.  If antibodies are found, this indicates the chicken has recently been exposed to encephalitis virus that was transmitted through the bite of a mosquito, Because those mosquitoes may also feed on humans, there is an encephalitis risk.
Another recently developed method of detecting the presence of encephalitis in wild mosquito populations involves trapping mosquitoes, grinding them up and testing for encephalitis RNA. If present, the potential exists for transmission to humans. This test is called CR (polymerase chain reaction) testing which is similar to the DNA testing used as evidence in court to tie a particular individual to a crime scene.
When constant monitoring shows a potential for encephalitis transmission to humans, mosquito control programs target the species capable of carrying the disease.back

5. How can children be protected from encephalitis?
Because St. Louis encephalitis (SLE) and eastern equine encephalitis (EEE) can only be acquired through the bite of an infected mosquito, the simple way to reduce disease risk is to avoid being bitten by mosquitoes. Mosquitoes are generally more active during the hours near dawn and dusk.  Indoor activities should be planned for those times, particularly when encephalitis alerts are given.  Light colored, long sleeved, slightly baggy clothing will give greater protection.  Scented products (colognes, hair spray, deodorants, and etc.) may attract mosquitoes.  Repellents (between 7 and 30 percent DEET is recommended) should be used according to their labels, which are approved by the EPA.  Proper use of commercially available mosquito repellents reduces the likelihood of being bitten by mosquitoes.back

6. Are chickens infected with encephalitis dangerous to people?
No Saint Louis encephalitis (SLE) is transmitted to people through the bite of an
infected mosquito. Being near chickens, eating eggs or chicken meat will not
cause SLE, even if the chicken was infected back

7.  Are the chemicals harmful to people or pets?
Any chemical, even salt or caffeine, in a large enough dose can be harmful.  The amount of mosquito control chemicals that come out of the mosquito trucks and aircraft are not harmful to humans or pets.  As with any chemical, it is always a good idea to keep exposure to a minimum.  For this reason, children should not be allowed to follow the mosquito trucks as people often did in the 1940s and 1950s.  Pets usually are repelled by the high pitch of the machine.  It can be difficult to see or smell the insecticide coming out of the truck or plane. Therefore, even if it seems that they are not spraying, the trucks should not be followed.  A person or pet that accidentally gets hit with the spray may feel a momentary slight burning or stinging sensation on the skin or in the eyes and may cough briefly if they inhale the spray.  The smell is usually worse than the taste or sting. Unless someone is very sensitive or allergic to chemicals, washing the skin with water is all that is needed.  At the low insecticide dosage used, no other symptoms, should be experienced. If other symptoms are experienced, a physician should be consulted immediately. People who are chemically sensitive should give their names to their local mosquito control program so they can notified prior to any spraying. back

8.  Do any of the chemicals cause cancer?
According to available research, a homeowner is not in danger of contracting cancer from mosquito pesticides sprayed infrequently and low doses by mosquito control programs.  All but one of the mosquito control chemicals are “non-restricted use”pesticides.  That puts them in the same category as the garden and household sprays, which can be purchased at the store.  In fact, one common mosquito Adulticides (Malathion) is a very common home and garden insecticide.  Mosquito control uses these insecticides in much smaller quantities than might be used to control larger insect pests, like wasps and cockroaches, because mosquitoes are much smaller.  Most mosquito sprays are too weak even to kill houseflies back

9. How will the spray effect people or pets if it is inhaled or if it lands on the skin?
Any person or pet that accidentally gets hit by the spray may feel a momentary slight stinging or burning sensation on the skin or in the eyes.  Unless a person is very sensitive or allergic to chemicals, washing the skin with water is all the needs to be done.  At low insecticide dosage used, no other symptoms should be experienced.  If other symptoms are experienced, check with a physician. The mosquito control program maintains a list of chemically sensitive persons who are called before their area is sprayed.back

10. How soon after spraying can children go outside.
The pesticides used to control adult mosquitoes have been registered by the Environmental Protection Agency and reviewed by the State Department of Agricultural and Consumer Services for use around commercial, agricultural and residential areas. These aerosol sprays are almost invisible because of their extremely small size. Because these spray droplets are very small, they float in the air and therefore, usually float around objects and people. Scientific studies have shown that people standing or jogging had negligible contact with spray materials during spraying operations. Spray equipment is designed to scatter the spray material from the spray truck. Therefore, children can safely go out side immediately after spraying as long as they remain a distance of twenty-five feet from the spray truck. back

11.  What are the symptoms of organohosphate insecticide poisoning?
Organophosphate insecticide poisoning usually results after prolonged exposure to, misuse of, or direct contact with a concentrated pesticide product. Misuse of label instructions or accidental spillage may result in injury to an individual or contamination of water sources. Headache, nausea, vomiting, dizziness, burns, profuse sweating, and unconsciousness are some of the symptoms which may be experienced when significant poisoning has occurred.  It is for this reason that an individual must know what has been sprayed.  ALWAYS READ AND FOLLOW THE LABEL!  If poisoning is suspected or has occurred, call the poison control or seek medical advice immediately. If possible have the label with you when you call.

FLORIDA POISON CONTROL CENTER

14. Why do mosquitoes leave welts on the skin when they bite?
When the female mosquito pierces the skin for her “blood meal”, she injects a small amount of saliva into a capillary, the blood vessel closest to the skin. The saliva makes penetration of he proboscis (mouthparts) easier and prevents the blood from clotting.  Welts or red 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 welt up more. Some people may be more allergic to specific species of mosquito than other species. 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 wounds, as bacteria from the fingernails may be introduced into the wound and cause infection. back

15. Why do people seem to react more to some mosquito bites than to other?
The female mosquito needs the protein in blood to produce her eggs. The female mosquito injects saliva into the bite to keep blood from clotting. This makes it easier for her to suck up the blood. The cells of the immune system rush to the site of the bite and try to get rid of the saliva. As a result, there is swelling and itching-an allergic reaction. Some people tend to welt up more than others do because they are more allergic to the mosquito’s saliva. There are over seventy species of mosquitoes in the state of Florida. People maybe highly allergic to one species of mosquito and not very allergic to another species. For this reason, some mosquito bites may cause greater reaction than others. back

Other Control Measures

1. What can people do to reduce mosquitoes?
There are many things that homeowners can do to reduce mosquito problems. These include:

• empty all pans and saucers under potted plants
• eliminate any standing water in the yard and keep grass mowed
• keep all rood gutters clean and clear of debris
• replace water in pet dishes every couple of days
• cover trash or “spare parts”
• discard old tires or stack flat and keep them covered
• cover rain barrels with screening
• maintain swimming and wading pools
• flush bromeliads with fresh water every few days
• fill three holes with sand or cement
• remove debris from flat roofs
• stock natural or man-made ponds with mosquito fish
• keep boats covered and the bilge empty
• keep bird baths, barbecue grills, wheelbarrows, etc. overturned or flushed once a week.
• flush large animal water troughs weekly

Yards should be checked for mosquito breeding in all of the above locations. A small amount of water can breed hundreds of mosquito larvae! Mosquito control will gladly send a technician out to check yards and show homeowners what mosquito larvae look like so they can check for breeding on their own. back

2. What are some alternatives to pesticides for mosquito control?
     There are a few alternatives to pesticides for controlling adult mosquitoes. Mosquito control operates under an Integrated Mosquito Management (IMM) philosophy. This means using a combination of mechanical, biological and chemical control methods. However, sometimes there is no alternative to chemical control.

Source reduction, or reducing the amount of standing water available for mosquito breeding, is a viable alternative. There are several other alternatives. Vertebrate predators such as fish and birds, invertebrate predators such as insects and flatworms, pathogens, which are bacteria fungi or viruses and botanicals which are derived from plants, are all effective at reducing mosquitoes.

      One of the more successful alternatives to pesticides for controlling mosquitoes is the use of Gambusia, also known as mosquito fish, which can eat large numbers of mosquito larvae.

Mosquito control does not recommend the use of following alternatives to pesticides:

• bug zappers
• citrosa plants
• bug lights
• ultrasonic devices

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3. How effective are Citrosa plants?
     The Citrosa plant will, when the leaves are moved, release citronella, a natural and well-known, but not always effective, mosquito repellent. Citronella is sold as a repellent in lotion form but is more commonly sold as citronella candles. The candles, used in groups, can be effective as long as the citronella lemony smell is present. However, some studies have shown that Citrosa plants do not repel mosquitoes or keep them from biting humans that are nearby, even when the leaves are crushed and the citronella smell is released. In fact, mosquitoes freely land on the plant and feed on it, sucking sugar from the stems.

There are no known plants that, when planted near houses, prevent mosquitoes from entering the building or from biting humans that pass them.

The best method to prevent mosquito bites is to wear loose clothing that covers the skin and apply commercial repellent that contains 7% to 30% DEET on exposed skin or on the clothing.  Please read the directions on the repellent container before use.  DEET is absorbed into the skin; therefore higher concentrations of DEET increase the potential for skin reactions to the repellent. back

4. How effective are bug zappers?
Regardless of the brand name or type of light, bug zappers do not reduce the number of mosquito bites you will get. Studies have shown that although mosquitoes are killed by the devices, their light attract more mosquitoes into the area than would be there without the devices, just like a porch light. Yes, they kill mosquitoes but they also kill beneficial insects like dragonflies. Thus, they are not recommended. If you already own a bug zapper and want to use it just to get the satisfaction of hearing the “zap”, then place it where it will attract mosquitoes away from the area you want to protect. back

5. What is the best personal repellent?
It has long been known that the most effective repellents are those which contain DEET.  DEET is the abbreviation for the chemical N.N-diethyl-meta-toluamide.  DEET has been sold in the United States since 1956 and is used by 50-100 million people each year.  It repels mosquitoes, no-see-ums, fleas, ticks, gnats, horse flies, deer flies, yellow flies and chiggers.  Repellents containing DEET are available as pump sprays, aerosols, lotions, creams, soaps and sticks. In general, the more inexpensive products contain less than 10%DEET, while the more expensive ones are at least 20%DEET.  There are over 40 products containing from 5% TO 95% DEET, which can be purchased.  Products with more than 35% are available, most often, through camping and outdoor supply stores.  If a little DEET is good, is a lot of DEET better?  Not necessarily.  In tests done by the army, repellents with 30-40% DEET worked twice as well as repellents with 75% DEET.

Read the label and check to see what percentage of the product is DEET. This information is found under active ingredients. The label may say DEET, or it may spell out the chemical name.  Some people need to use higher concentrations, while a lesser concentration may suffice for others.  It is always best to use the lowest concentration that is effective.  People should check to see if it is a controlled release formula  (long lasting) and compare the amount of product and the type of application.  Lotions provide the most even coverage. Sprays are more convenient but require greater care in applying. The entire label should be read before choosing what is best for a family. back
   
6. What can be done when tons of mosquitoes are clinging to the house?
Male mosquitoes swarm during mating season. Some will rest on the sides of a house together. Both make and female mosquitoes will seek shade during hot weather and, if a house offers cool, shady resting spots, then mosquitoes will cling to the walls. A sample of the mosquitoes collected for the technicians may reveal that they are not biting mosquitoes

Often large swarms of midges cling to the sides of buildings. These look very much like mosquitoes, but do not bite. They are often called “blind” mosquitoes. If they are determined to be mosquitoes, there may be a serious breeding problem in the vicinity of the house. If the problem keeps reoccurring, mosquito control can send a technician to inspect the areas around the house. They will more than likely be able to find where the problem is and take care of it.

To eliminate the immediate problem of adult mosquitoes clinging to the house, spray the bristles of a broom with mosquito repellent and sweeps them from where they are clinging. There are many repellents and sprays available to keep mosquitoes away from a house. Mosquito Control does not recommend bug zappers, citrosa plants or any other control technique that does not include eliminating all water sources to reduce potential mosquito breeding sites.

7. Is there something, which can be used to stop mosquitoes from mating instead of using pesticide?
There are a variety of methods used to kill mosquitoes; spraying adults is only one.  It is also the most visible method a program might use. Some other methods used by mosquito control programs are as follow: (Check appropriate items.)

1. applying pesticides to water to kill mosquito larvae
2. stocking mosquito fish in permanent ponds
3. draining areas before mosquito larvae can become adults
4. flooding areas to prevent mosquitoes from breeding
5. eliminating containers that breed mosquitoes
6. advising people how to reduce mosquitoes in their yard.

People can help reduce the mosquito problem by checking back yards for containers, even very small ones that hold water. Citizens should look for pet dishes, tin cans, flower pot holders, plugged gutters, tires, bird baths, kiddy pools, toys, bromeliads-anything. Water should be dumped every third day if the source is not eliminated. Containers that are too large to turn over should be covered.

Unfortunately, there is no way to stop mosquitoes from mating.  Although they eat larvae and adult mosquitoes, bats, birds and other vertebrates do not control mosquitoes to the level people demand or the level that prevents disease transmission .back

Environment

1. How can one type of insect be controlled without harming other insects or wildlife?
There are three important factors, which allow mosquito control applicators to target mosquitoes, while having a minimal effect on other organism. These include the way insecticides kill, the amount of insecticide sprayed and the time the insecticide is sprayed.

First, modern pesticides have become more specific as to what they will affect when used in the correct amounts. For example, pesticides, which kill only insects, affect parts of the insect that other animals and plants do not possess.  Just as rat poison, when used in the proper amount, does not kill insects and weed killer does not kill birds, mosquito pesticides, when used in the proper amounts, do not kill birds or rats. Most of the pesticides used to kill mosquito larvae have minimal effects on other organisms.

Second, the amount of pesticide, or dose, is an important factor.  The pesticides that are used to kill adult mosquitoes can, and do kill certain other insects, particularly those that are similar to mosquitoes, such as blind mosquitoes, no-see-ums (biting midges) and other small insects. They do not kill larger insects like houseflies, butterflies, horse flies or beetles because the dose applied is not high enough.

Third, while some insecticides used to kill adult mosquitoes can kill bees, they are not used during the day when bees, and many other insets, are flying around. They are used at dusk of at might when the mosquitoes are flying and the bees are not. That’s one reason trucks do not spray during the day. back

2. What methods are used to kill mosquitoes and are they environmentally safe?
There are four basic approaches to controlling mosquitoes: prevention, source reduction, larviciding and adulticiding. Preventing mosquitoes from breeding is the most desirable solution. Unfortunately, many human modifications of the environment such as ditches, retention ponds, and water management structures create mosquito breeding sites.  Prevention requires educating planners about how to plan, construct and maintain infrastructure with out producing mosquito breeding habitats.

Source reduction is the elimination of water in which mosquitoes lay their eggs and in which the larvae develop.  This is the second most effective method for controlling mosquitoes. Methods of source reduction involve eliminating yard containers that hold water and filling wet areas with soil.  Some coastal salt marsh areas are impounded, keeping water in the area during the mosquito season. This eliminates areas for mosquitoes to lay their eggs.

Larviciding is the use of chemicals and mosquitofish to kill the immature stages of mosquitoes. Larvicides are applied to waters that contain larvae and pupae. Today’s modern larvicides are effective in low concentrations and generally do not impact other organisms in the water or habitat. Every acre that is larvicided to prevent adult mosquitoes from emerging reduces the number of acres that must be treated with the familiar spray or fog trucks.back

3. Is spray dangerous to butterflies?
Depending upon the type of chemical used, the spray might kill some individuals in certain species of butterflies or caterpillars. However, any adverse effects on butterfly populations will most likely be very localized and temporary. back

4. Does the spray used by mosquito control programs kill good insects and birds?
When applied as directed by the usage label that comes with the insecticides, adverse effects on population of non-target organisms, like mammals, birds, and fish are usually absent or very minor. However, some insects (for example, honeybees) could be killed by mosquito sprays. Fortunately, mosquito adulticiding is normally done during the time of the when bees are resting in their hives where they are less likely to be killed by spraying. Also, when planning a mosquito spraying operation, efforts are made to avoid spraying near areas know to contain beehives. back

Mosquito Control Operations

1. What is the best way to control mosquitoes?
The best way is to eliminate the water in which they breed. Back yards should be checked for containers even very small ones, that hold water. Pet dishes, tin cans, flower pot holders, plugged gutters, tires, bird baths, kiddy pools, toys, bromeliads-anything that can hold water should be checked. Water should be dumped every third day if the source is not eliminated.  Those containers that are too large to turn over should be covered. While it is possible to drain larger wet areas or flood them so, mosquitoes can not breed, those methods are generally not good for wildlife. Sometime it is possible to add fish, which eat mosquito larvae in the pond. The next best method is to control mosquitoes by treating the water with insecticides that kill only mosquitoes.  There are four such insecticides.  This program uses b.t.i., Methoprene (Altosid), Temephos (Abate) and oils.

Unfortunately, there is no way to stop mosquitoes from mating and, although bats, birds, other insects and vertebrates eat mosquito larvae, they do not control mosquitoes to the level people want or that will prevent disease transmission. back

2. What are the requirements for spraying adult mosquitoes?
Requirements are based on criteria provided by the state, and at least one of the following criteria must be documented:

1. When a large population of adult mosquitoes is present, a standard surveillance method, such as landing rates or traps must document this increase or s sustained high level of mosquitoes.
2. Where adult mosquito Populations build to levels exceeding 25 mosquitoes per trap hour during dawn or dusk periods.
3. When mosquito service requests have been confirmed by standard surveillance methods, i.e. traps and/or landing rates.
4. Aircraft applications along beaches and bayshores only when there is a three- fold increase over the normal mosquito population levels.back 

 

3.  What criteria are used when deciding where to spray?
Spraying for larval mosquitoes occurs only when problem species of mosquito larvae have been detected in large numbers. This involves constant monitoring of mosquitoes in larval populations, which will soon advance to the adult stage where they become problems for humans.

Spraying for adult mosquitoes occurs only after the targeted species of mosquitoes have reached a point where they have become a problem as documented by trap counts or citizen requests for spraying. In order to spray for mosquitoes, certain types of mosquitoes must be found in significant numbers. back

4.  How often do mosquito control programs spray for mosquitoes?
Spraying for problem adult mosquitoes occurs only on an as needed basis. The need for adult mosquito spraying can vary greatly from one year to the next due to environmental conditions, especially rainfall and tides.

Most mosquito control programs conduct on-going trapping of mosquitoes to determine what species are present in high numbers. Typically, only a few species in an area are capable of causing disease problems for people. If a species of mosquito starts is increasing in number to the point where it becomes a problem for humans, mosquito control efforts begin.

Besides trapping for adult mosquitoes, citizens experiencing high numbers of mosquitoes around their homes often call the mosquito control program to request spraying. Individual spraying of home sites for mosquitoes is not an efficient method of mosquito control. However, the calls are important because they alert mosquito control officials to regional problems when the patterns of calls are elevated. The calls alert officials to potential problems and the trapping confirms the need for control. back

5. Do mosquito control programs spray for things other than mosquitoes
Mosquito control exists only to help prevent health problems caused by the mosquito. The pesticides used are only labeled for the treatment of mosquitoes. For these reasons, mosquito control does not treat for ants or other insect pest. Some programs do spray for other insects such as dog flies, sand flies yellow flies. back

6. How effective is the spray?
Pesticides properly applied to water kill 95% - 100% of the mosquito larvae and, thus, are very effective. It is more difficult to tell how effective sprays to kill mosquitoes are, because it is not known exactly how many mosquitoes are present before spraying. Adult sprays applied by aircraft are very effective because the spray covers a very large area, usually several square miles. Reductions of 90% are common. Adult sprays applied by trucks can be just as effective where parallel roads are close together, where there is a light wind and the vegetation around houses is not thick. It is the less effective if there is no wind, high humidity, too few roads and heavy vegetation. Traps are often used to measure population levels before and after spraying. back

7. Why can’t mosquito control programs spray during the day?
It is not effective to spray during the day for several reasons. The primary reason is that the spray would be lifted away from the ground very quickly by the rising air currents that occur during hot Florida days. At dusk and at night, the insecticide stays near the ground.

The second reason is that most mosquitoes that bite during the day (Asian Tiger mosquito, yellow fever mosquito and bromeliad mosquitoes) are breeding in containers or plants in the yard and are better controlled by eliminating the water in which they grow.

Mosquito problems can be reduced by checking yards for containers, even very small ones that hold water. People should look for pet dishes, tin cans, flower pots, plugged gutters, tire, bird baths, kiddy pools, toys, bromeliads, trash cans – anything. Water should be dumped every third day if the is not eliminated. Containers that are too large to turn over should be covered. Daytime spraying is not practiced to avoid killing beneficial insects, particularly bees; to reduce people’s and wildlife’s exposure to the pesticide; and to eliminate the potential traffic hazard of a slow moving vehicle during high traffic volume times. The mosquito control vehicle’s slow moving, flashing light and unique sound is easily seen and identified at night. back

8. Can mosquito control programs spray ahead of time for special events, sporting events, garden weddings, parties, etc.?
It is against State regulations to spray for mosquitoes prior to any surveillance. However, if mosquito control is notified of the date and time the event is to be, surveillance in the area could be increased. This would determine if treatment would be required before a function began. Many events do not need spraying because the event is held during the day when most mosquitoes are less active and therefore less annoying.  back

9. Do mosquito control programs spray over the beach?
Pesticides labeled for use in Florida (by the Environmental Protection Agency) to control adult mosquitoes are not to be applied to open water, such as bays and lagoons. Aircraft may release sprays over water to drift over the land when wind speed and direction is sufficient to carry the spray to land. In controlling mosquito larvae however, the spray (larvicide) is often directly to the flooded salt marshes and other wetlands. These sprays are formulated to control mosquitoes without adversely affecting other organisms.  back

10. How long do the chemicals last once they have been sprayed?
The longevity of a chemical depends on the chemical used and the weather conditions at the time of the application. Weather in the immediate area of the spraying affects chemical droplet dispersion and deposit and ultimately its effectiveness. In general, depending on the chemical used, it can be gone within 15 minutes of the application or last almost 4 hours after application. This mosquito control program uses Malathion, it will last1 to 4 hours from the time of application until complete dispersal. Permethrin and Dibrom are used because they act and disperse quickly. back

11. How can citizens find out when spraying will occur?
To find out when spraying will occur, call the mosquito control office at (850) 233-5030.
Because mosquito trap counts and citizens complaints are used to determine the location for spraying, it is impossible to determine the spray schedule more than a day or two in advance. back

12. Why do mosquito control helicopters fly around but not spray?
Helicopters perform surveillance, larviciding, transportation and adulticiding tasks for mosquito programs. These tasks may include:

Checking areas (including breeding sites) for flooding and future breeding potential,

Checking known breeding sites for adult and larval mosquitoes,

Checking aquatic weed control measures,

Applying liquid larvicides  to breeding sites (this application would not make a fog),

Applying granular larvicides to breeding sites,

Transporting technicians into inaccessible breeding sites to enable them to treat the mosquito breeding with hand sprayers. back

13. Why can’t the spray be seen coming out like before?
The spray that you used to see during mosquito spraying was produced by the use of diesel oil of fog oil. This oil acted as a carrier to help disperse the pesticide in the proper concentrations. Newer methods of spraying called ultra low volume or ULV have eliminated the need for the oil therefore no fog is seen during the spraying. This newer method still provides effective control of mosquitoes and eliminates the adverse health and environmental effects of the oil. back

14. Who over sees pesticide applications?
Florida mosquito control programs are established and operated according to the procedures given in the Mosquito Control Law, Chapter 388 Florida Statue (F.S.) and the Mosquito Control Rules, Chapter 5E-13, Florida Administrative Code (F.A.C.).

The Federal Insecticide, Fungicide and Rodenticide Act of 1972 (FIFRA) requires that the Environmental Protection Agency (EPA) be certain that all personnel handling hazardous or restricted chemicals be trained to do so correctly and safely and that they be certified as pesticide applicators.

The state agency administering the certification is appointed by the governor of each state. In Florida, the Department of Agriculture and Consumer Services (DACS) is the lead agency.

The law requires that every person applying pesticides be certified or be supervised by a certified applicator. Every Florida district and program goes to great lengths to see that all personnel are trained in proper handling, use and application of pesticides. There are training courses offered throughout the year and each winter there is a week long short course which offers job specific training. This training results in certification of all mosquito control personnel. Program directors must abide by a number of laws and regulations to provide for the safe use of pesticides by all employees. Directors are obligated to meet the requirements of the right to know law and the Occupational Safety and Health Act (OSHA). Ultimately, directors are responsible for everything that goes on within their administration. back