We do not offer mosquito control services at this time.  We have included this information about mosquitoes and West Nile Virus to help you and your family develop an action plan and mosquito management program to fight this potentially dangerous disease. All of the information we present has been published in various newspapers and government pamphlets. But, just in case you need a quick reference, you'll find it here. Our information is continually updated and we hope you find it helpful.

The good news is that if you have bats on your property, hopefully living in their own bat houses, you will have less mosquitoes.  Bats will consume 600 mosquitoes per hour per bat.  We think that's great and love having bats around to perform this important pest control service for us.

Experience has shown that mosquitoes must be in fairly dense fog for a minimum of 20-30 seconds to be effective.  If exposed for a lesser period of time, they are likely to survive.  Atmospheric conditions (wind and temperature) also must be perfect.  In consideration of these factors, the average customer would not find a professional fogging service cost-effective for the very short-term results.  There are mosquito control experts available who hold appropriate licences to perform mosquito control and larvicide treatments to ponds, and other standing water on your property. If you do choose to use this service, check that the larvicides being used are non-toxic. 

Mosquito control is complicated by the fact that the adults move about.  Although many adults may travel less than one mile from their breeding sites, they can fly or be carried by the wind several miles.  In addition to protective clothing, repellents on the skin, and citronella products, you can greatly reduce mosquito populations by reducing their breeding and resting areas.  Dense vegetation is a very attractive resting place for mosquitoes since it protects them against the wind and sun.  Keep weeds and grass mowed, trim hedges and remove unnecessary shrubs and trees.  Mosquitoes can breed in any pool of standing water.  Breeding sites include water in tin cans, pails, clogged eaves troughs, birdbaths, rain barrels, clogged drainage ditches, old tires, wading pools and poorly maintained swimming pools.  Draining them or changing the water at least once a week can eliminate all of these breeding sites.  Check your property for these breeding sites in the early spring;  the larvae will be evident as they wriggle to the water's surface to breathe. If you follow the advice in these articles you will be able to reduce your mosquito population this season.

There are many species of mosquitoes, each of which has a different habitat, behaviour and preferred source of blood.  About ten of these species are so numerous, and such vicious biters of man and animals, that many counties establish agencies to control mosquitoes. The Culex pipiens variety carries West Nile Virus.

Mosquito Biology

Order Diptera

Family Culicidae, Subfamily Culicinae

Mosquitoes develop in water from the tropics to the arctic regions and are the only known means of transmission of the causal agents of malaria, yellow fever, some types of encephalitis, dengue, and filariasis. And, of course, the Culex pipiens variety carries West Nile Virus. All of these, with the exception of filariasis, have been common in North America in the past. Extensive control measures by public health officials have virtually eliminated all but encephalitis and the West Nile Virus. Mosquitoes are also severe pests because of their annoyance to people, and many good recreational areas are not usable at certain periods of the year because of mosquitoes.

Mosquitoes can be distinguished easily from other flies by the fact that they have both a long, piercing proboscis and scales on the hind margin and veins of their wings.

Approximately 150 species of mosquitoes belonging to 12 genera are found in North America.  Only a few of these are of importance as carriers of disease organisms but many more are important as nuisances.

Mosquitoes have a complete metamorphosis.  Eggs are laid, either singly or in bunches, on a water surface or in a place where they will become wet when flooding occurs.

Mosquito larvae and pupae live in water.  Various species have become adapted to living in practically all kinds of water except fast-flowing streams and the open portions of large bodies of water where there is considerable wave action.  The choice of type of water for larvae is generally quite specific, and the discussion of individual mosquitoes in this chapter will be by type of water habitat.

Mosquito larvae live in water, but they must either surface for air or obtain it from the underwater portions of plants.  Larvae have a well-defined head, thorax and abdomen.  Most species move about actively in the water and come to the surface frequently to breathe.  They assume characteristic positions when at the surface of the water.  Anopheline larvae lie parallel to the surface while most other groups hand head down with the tip of the air tube extending to the water surface.

Larvae go through 4 instars, usually in a period of 4 to 10 days, to form the pupa.  The pupa lives in water and like the larva is quite active.  The head and thorax are greatly enlarged and enclosed in a sheath.  A pair of respiratory tubes project from he upper surface.  Most species are lighter than water so that, when they are not actively swimming, they rise to the surface where the respiratory tubes contact the open air for breathing.  The pupal stage lasts from 1 day to as long as a few weeks.  When ready to hatch the pupa rises to the surface and the pupal skin breaks.  The adult works its way out of the pupal skin which it uses fro support until the body wall has hardened to the extent that the adult is capable of flight.  Males usually emerge first and wait near the hatching point to mate with the females soon after they emerge.  Most female mosquitoes must have a blood meal before they can lay fertile eggs.  The adult female is the only stage which feeds on blood.  The mouthparts of the adult male are not suitable for blood-sucking.  Therefore, their nourishment is normally derived from nectar and plant juices.

Identification

There are a set of Identification Keys to identify the mosquito species. For example, the culex pipiens which carries West Nile Virus,  has an abdomen with broad rounded pale bands and its thorax does not have any pale dots on it as some other species do. A general, if not, advanced knowledge of entomology will enable you to identify this mosquito if one is caught and examined under a magnifying glass. This standardized set of keys used throughout the pest control industry by specialists in mosquito control are based on female mosquitoes as it is necessary to be able to distinguish the females from the males. This can easily be done by looking at the antennae;  male antennae are bushy while female antennae are not. Larval identification is widely used as well since control efforts must frequently be directed at this stage of the mosquito.

Mosquitoes of Natural Cavities and Artificial Containers-Culex pipiens-West Nile Virus Carriers
Mosquitoes of this group lay their eggs in water entrapped in such places as tree holes, tin cans, rain barrels, roof guttering and catch basins.

Culex pipiens pipiens Linnaeus, the northern house mosquito, is found throughout the northern United States and Canada and as far south as Georgia and Oklahoma. Culex pipiens quinque fasciatus Say, the southern house mosquito, occurs in all of the southern states from coast-to-coast and as far north as Nebraska, Iowa, Illinois and Ohio.  One or both of these subspecies is probably found in every state. Adults of both are medium size, brown, with cross bands of white scales on the abdominal segments.

Eggs are laid in clusters or rafts of 200 to 400 on the surface of water.  These hatch in 1 to 2 days.  The larval and pupal stages together may require as little as 8 to 10 days before hatching into adults.  Breeding is continuous during warm weather.  The larvae of this mosquito also are found in open water.

These are the most common mosquitoes in many towns as well as in rural areas.  They commonly enter houses and are severe biters.  They both commonly carry the virus of St. Louis encephalitis and West Nile virus.

West Nile Virus (excerpts from Toronto Star, Toronto Sun, and Ministry of Health) Find out more about West Nile virus by calling the Ontario Ministry of Health INFO line at 1.877.234.4343 (toll free in Ontario or contact your local public health unit. Visit the Ministry of Health Web site at www.HealthyOntario.com

First seen in Africa in 1937, West Nile Virus came to Ontario in the late 90's. With more than 300 confirmed cases of West Nile virus and 17 deaths in Ontario last summer, health officials are taking a get tough approach to combat what may prove to be an unprecedented season for the mosquito-borne illness this year.

How the Virus is Spread
West Nile virus is spread to humans by the bite of an infected mosquito. Mosquitoes become infected when they bite an infected bird. The virus is not spread by person-to-person contact through touching, coughing, sneezing, or drinking from the same cup.

There is some evidence that a person can be infected by handling a dead bird, however, the risk is very low.  Wear gloves or use a thick plastic bag if you have to handle a dead bird.

West Nile virus is not know to be transmitted from mammals, such as horses, to humans.

How to Protect Yourself
Use insect repellent.  Consider using a personal insect repellent containing DEET (N, N-diethyl-m-toluamide) with a concentration of no more than 30% for adults and no greater than 10% for children over 2 years old. DEET products should always be used sparingly on children, avoid the face and hands, apply only once per day, and use the least concentrated product containing 10% or less DEET.

Tips for using insect repellent: 

• do not use repellent on open wounds, or if skin is irritated or sunburned
• do not get in eyes - if this happens, rinse with water right away
• wash skin with soap and water when you return indoors or when protection is no longer needed
• avoid breathing mist from spray-type repellent - always apply in a well-ventilated area; never apply spray repellent inside a tent and do not use near food
• check for sensitivity - apply repellent to a small area of skin on the arm and wait for 24 hours before use
• read the manufacturer's instructions on the label carefully

• Protect babies under 2 years old by using mosquito netting around the carriage. Health Canada advises that DEET-containing repellents are not to be used on children under 6 months of age and recommends that where there is a high risk of complications to the child from insect bites, DEET may be considered for children aged 6 months to 2 years.
• Gardeners take note - if you like to work outside, avoid early morning and evening when mosquitoes are most active.
• Cover up with clothing including mosquito net hats, jackets etc.- wear light colours of clothing when going outside between the hours of dusk and dawn because mosquitoes are attracted to darker, more intense colours. Wear long-sleeved shirts or jackets, long pants and tuck pants into socks for extra protection.

Clean Up  ( all around your house and cottage)
The best way to keep mosquitoes away is to clean up areas where they like to breed. Unlike birds or other insects, mosquitoes do not fly very far and tend to stay close to their breeding sites and normal habitat. Take a look around your house and property and get rid of places that are mosquito-friendly that would make good breeding sites or resting places for mosquitoes.

• Any type of standing water:
  • clean up and empty containers of standing water such as old tire, flower pots, wheelbarrows, barrels or tin cans that are outdoors
  • drill holes in the bottoms of used containers so water can't collect
  • change water in bird baths every other day
• Swimming or wading pools:
  • immediately remove water that collects on pool covers
  • make sure the pool's pump is circulating
  • turn over wading pools when not in use
• Check eaves and drains:
  • don't let things pile up - clear leaves and twigs from eaves troughs, storm and roof gutters throughout the summer
  • make sure drainage ditches are not clogged
  • check flat roofs frequently for standing water
• Yard and lawn maintenance - think mosquito prevention when working in the yard. Lawn cuttings, raked leaves or other decaying debris such as apples or berries that fall from trees should be collected and recycled or mulched so that organic matter does not end up in storm sewers as a food source for mosquito larvae.
  • turn over compost frequently
  • fill in low depressions in lawn areas
  • clear out dense shrubbery where mosquitoes like to rest
  • spread the word - point out potential mosquito breeding areas to friends and neighbours
• Check windows:
  • check window screens for holes and make sure they fit snugly into the window frame, so mosquitoes will not get indoors
  • if you don't have screens, consider keeping windows closed between the hours of dusk and dawn when mosquitoes are most active

  Health Canada launches National West Nile Virus Info-line

  OTTAWA - Today the Honourable Anne McLellan, Minister of Health, announced the launch of Health Canada’s West Nile Virus Info-line.

  “Health Canada is committed to ensuring Canadians have timely and accurate information about West Nile virus,” said the Minister. “This toll-free line will help Canadians to be informed of the risks and what they can do to lower their risk of infection.”

  The toll-free line is 1-800-816-7292. Canadians can also get information on the Health Canada Web site at: www.westnilevirus.gc.ca
  
  With the onset of mosquito season, Health Canada would like to remind Canadians about the preventative measures they can take to protect themselves from West Nile virus.

  These measures are detailed on the Health Canada Web site, and will be available through the toll-free line. Measures include: how to reduce mosquito breeding grounds around their homes or cottages, and how to protect themselves from mosquito bites, including the use of insect repellents that contain DEET or other approved ingredients.

  The Pest Management Regulatory Agency recently completed an assessment of insect repellents containing DEET. Canadians should become familiar with the new use directions for these products. They can be found on the Health Canada Web site at: http://www.hc-sc.gc.ca/pmra-arla/english/pdf/pnotes/deet-e.pdf

  Health Canada remains committed to ensuring all Canadians have access to credible, reliable and timely information about West Nile virus, and continues to work with its many partners to discover, analyze and communicate new information.

  Research on West Nile Virus - December 2002

  Overview

  West Nile virus belongs to a group of disease-causing viruses known as flaviviruses, which are spread by insects, usually mosquitoes. Other flaviviruses include yellow fever virus, Japanese encephalitis virus, dengue virus, and Saint Louis encephalitis virus. West Nile virus is the most familiar flavivirus and represents an emerging infectious disease in the United States. Most human infections are mild, causing fever, headache and body aches, often accompanied by a skin rash and swollen lymph glands. If the virus crosses the blood-brain barrier, however, it can cause life-threatening encephalitis (inflammation of the brain) or meningitis (inflammation of the lining of the brain and spinal cord). Recent cases have indicated that West Nile virus can be transmitted by transfusion or transplantation. In addition, it appears that West Nile virus can also be transmitted from mother to child before birth and through breast milk.

  The first step in the transmission cycle of West Nile virus occurs when a mosquito bites an infected bird. Although the virus primarily cycles between mosquitoes and birds, infected female mosquitoes can transmit West Nile virus to incidental hosts, including humans, when taking a blood meal. Crows are commonly associated with the virus because they are highly susceptible to infection, but scientists have identified at least 75 other infected bird species.

  West Nile virus was first isolated in Uganda in 1937. Today it is most commonly found in Africa, West Asia, Europe, and the Middle East. In 1999, it emerged in the Western Hemisphere for the first time in the New York City area. Although health officials hoped the virus would not survive the first winter, in early spring 2000 it re-emerged in birds and mosquitoes and spread to other parts of the eastern United States.

  Between 1999 and 2001, West Nile virus caused 18 deaths and sickened 131 other people. By the summer of 2002, the virus had spread west and south. As of December 20, state health departments had reported 3,852 cases of West Nile virus in people, resulting in 241 deaths so far in 2002 (see www.cdc.gov/od/oc/media/wncount.htm for the CDC's page about the current number of reported human cases of West Nile virus infections in the United States). Researchers continue to monitor and test birds and mosquitoes throughout the United States for evidence of the virus (see www.nationalatlas.gov/virusmap.html for the latest information).

  There are no drugs to treat the virus and no vaccines available to prevent infection. Because West Nile virus is now established in the United States, scientists and health experts at the National Institute of Allergy and Infectious Diseases (NIAID), along with public health officials, have enhanced research. This effort is part of NIAID’s comprehensive emerging infectious disease program, which supports research on bacterial, viral, and other types of disease-causing microbes.

   

  NIAID Research

  Research is underway to develop a vaccine, antiviral medicines, and new diagnostic assays for West Nile virus. Additionally, basic research is providing new clues about the virus itself, the disease in humans and animals, and how the virus is maintained in the environment. This knowledge is essential in developing strategies to prevent, treat, and eventually control this disease.

  In brief, these areas of research include

  • Basic research on the virus itself, on the disease in humans, and on its maintenance in nature
    NIAID supports basic research to better understand the host, pathogen, and environmental factors that influence disease emergence. For example, basic research is helping scientists determine which flavivirus proteins contribute to the virus' ability to cause disease. Researchers also investigate how protective immune responses are elicited within the central nervous system during acute flavivirus encephalitis.

    Factors influencing the pattern of emergence and distribution of West Nile include those associated with the virus itself, the agent's hosts and vectors, and the environment in which agent and host interact. The specific factors contributing to emergence of West Nile, however, are poorly understood. Nonetheless, knowledge of these principles is essential in planning strategies to prevent, treat, and control this disease. The overall objective of this basic research is to develop the knowledge and public health tools needed for the United States to combat West Nile virus.

    NIAID also supports researchers investigating how West Nile virus disseminates throughout the environment. An International Centers for Infectious Disease Research (ICIDR) program is supporting research in Mexico to study whether migrating bird populations carry the virus from its presumed point of entrance into the Western Hemisphere (New York City) to points in Central and South America. The emergence of West Nile virus in these new areas, which harbor abundant mosquito populations, could set up conditions for a potentially severe epidemic. Wild birds and chickens in the Yucatan Peninsula are being examined for evidence of exposure to West Nile virus.

    Researchers are also examining the ecology and persistence of mosquito-borne encephalitis viruses and the effect of genetic variation on the virus’ spread and virulence. They are examining how birds might be year-round reservoirs for the viruses that cause encephalomyelitis and St. Louis encephalitis. They are also comparing the genetics of St. Louis encephalitis viruses from throughout California and different parts of the United States to determine the rate at which the virus is changing, and whether birds carry it between discrete geographic areas.

    NIAID also supports research to better understand the insects and ticks that transmit flaviviruses. Such an understanding will allow improved monitoring and surveillance, and enable the development and preliminary testing of strategies to control carriers of the virus.

    Lastly, NIAID-supported basic research is important for maintaining the national and international scientific expertise required to respond to future health threats.

  • Research to prevent and control spread of the disease
    For several years, NIAID has supported research to develop a vaccine against West Nile. In 1999, NIAID funded a fast-track project to develop a candidate West Nile virus vaccine with Acambis. Since then, scientists have developed a prototype vaccine that has shown promise in animal tests. The vaccine is constructed using vaccine licensed for preventing yellow fever (caused by another flavivirus) as the backbone.

    For the West Nile vaccine, researchers substituted the surface protein of West Nile virus for the deleted yellow fever virus protein. This method of creating chimeric flavivirus vaccines is also being applied to developing a vaccine for dengue and Japanese encephalitis virus. The Acambis vaccine has undergone preclinical evaluations in in hamsters, mice, monkeys, and horses with encouraging results. The company is moving forward with Phase I trials. Vaccine is now being produced and an investigational new drug (IND) application will be filed with the Food and Drug Administration. Trials are anticipated to begin in early 2003.

    Other NIAID scientists, working on the National Institutes of Health (NIH) campus, also have developed a West Nile vaccine candidate which they have tested in monkeys with promising results. That vaccine uses an experimental dengue virus vaccine as a backbone. A DNA vaccine is also being explored through NIAID support.

    Last year, NIAID researchers developed a hamster model of West Nile virus, which closely mimics human disease. This animal model has proved useful in evaluating strategies for preventing the complications associated with this emerging infectious disease. Using this animal model, researchers were able to determine that prior infection with other related viruses provides complete or partial immunity to West Nile virus.

  • Research to treat the disease
    Drugs may be effective against West Nile virus because the infection is typically not chronic and antiviral drugs have been identified to be effective in vitro against other flaviviruses. The National Institutes of Health has funded investigators to establish a system to screen chemical compounds for possible antiviral activity against West Nile virus. Any promising antiviral drug candidates will be tested in the hamster model. This resource allows scientists to evaluate a drug’s safety and efficacy before moving on to possible human trials. Other research projects are investigating emerging diseases and developing candidate drugs to fight West Nile virus. More than 300 drugs have been screened, and twelve have shown promise for additional testing in animals. Immunotherapeutics (treatments that modify the body’s immune response) are also being explored.

     

  • Research to improve rapid diagnosis
    Research is also underway to allow for more rapid detection of West Nile in samples from humans, other animals, or vectoring mosquitoes. This research occurs mainly at small biotechnology companies attempting to develop new, commercially available diagnostic assays.

     

    Research Resources

    NIAID maintains the World Reference Center for Arboviruses at the University of Texas Medical Branch at Galveston, The Center has reference anti-West Nile virus sera and seed lots of various strains of the virus. This international program involves characterizing viruses transmitted to people and domestic animals by mosquitoes and other arthropods, and researching the epidemiology of arboviruses of the United States and overseas. During the last 3 years, these reagents were provided on request to investigators in the United States and Canada.

    NIAID has recently expanded its West Nile and related viruses research portfolio. This includes the establishment of two Emerging Viral Diseases Research Centers in New York and Texas, which include a focus on West Nile and related viruses. NIAID has also funded a project entitled "Development of Novel Antiviral Agents Against West NileVirus" under the Partnerships for Development of Novel Therapeutic and Vector-Control Strategies research initiative. In addition, many of the programs that have been recently developed and expanded for biodefense are available for other emerging infectious diseases, including West Nile.

    
    

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    NIAID is a component of the National Institutes of Health (NIH). NIAID supports basic and applied research to prevent, diagnose, and treat infectious and immune-mediated illnesses, including HIV/AIDS and other sexually transmitted diseases, illness from potential agents of bioterrorism, tuberculosis, malaria, autoimmune disorders, asthma and allergies.
    
    Press releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at http://www.niaid.nih.gov.
    
    Prepared by:
    Office of Communications and Public Liaison
    National Institute of Allergy and Infectious Diseases
    National Institutes of Health
    Bethesda, MD 20892
    
    U.S. Department of Health and Human Services