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Mosquito Surveillance Reporting Updates
Arboviruses are viruses that are spread to people by insect or tick bites such as West Nile Virus, Eastern Equine Encephalitis, and Chikungunya, Dengue, Powassan, Yellow Fever, and Zika.
Anyone can get an arbovirus, but young children and the elderly appear to be most affected and experience severe illness. People who travel or reside in areas where certain arboviruses are more prominent are at a higher risk to contract an arboviral disease. For example, Chikungunya is frequently found in Africa, Asia, the Caribbean, and Latin America while Powassan is found more in the northeastern and Great Lakes regions of the United States. The most prevalent Arboviruses in Massachusetts are West Nile Virus and Eastern Equine Encephalitis
Infected mosquitoes are the most common type of insect that spread arboviral disease. Not all mosquitoes carry the disease. Other arboviral infections, such as Powassan, are transmitted through a bite of an infected tick. Other ways arboviral disease is transmitted through blood transfusions, organ transplants, sexual contact, and from mother to child during pregnancy or delivery.
Symptoms typically appear from three to 14 days after a bite from an infected mosquito or tick. Symptoms of arboviruses can range from very mild to severe with most infected people experiencing no symptoms. Mild symptoms include a slight fever, headache, muscle, or joint pain, and/or a skin rash which can resolve without medical care. Severe infections can include headache, high fever, confusion, tremors, seizures, paralysis, coma, or death.
The Massachusetts Department of Public Health, in collaboration with the State Reclamation and Mosquito Control Board (SRMCB) and regional mosquito control projects (MCP), conducts surveillance for mosquito-borne viruses that pose a risk to human health. Surveillance currently focuses on West Nile (WNV) and eastern equine encephalitis (EEE) viruses, which are found in the local environment and are capable of causing serious illness and death in humans, horses, and other mammals.
The Town of Littleton contracts with Central Massachusetts Mosquito Control Project (CMMCP) for the following services:
• Adult mosquito surveillance
• Larval mosquito control with Vectolex WSP (biological agent)
• Ground applications of Bti (biological agent) at wetlands to control potential mosquito larvae
CMMCP provides an integrated mosquito management program including catch basin larval control program, surveillance and trapping, wetland inspections to monitor larval populations and identify obstructions in drainage systems. At this time, the Town of Littleton does not utilize aerial spraying as a means of mosquito control.
Based on mosquito surveillance and presence of animal and/or human cases of WNV and EEE, the Massachusetts Department of Public Health updates its current Risk Level for WNV and EEE in Littleton and other towns at least weekly during the summer mosquito season.
The product name of the mosquito adulticide used by the Central Massachusetts Mosquito Control Project is called Zenivex® E4. It is a 4% solution of etofenprox that does not contain piperonyl butoxide. Etofenprox is a reduced risk synthetic pyrethroid with an extremely low toxicity to mammals. It is sprayed from the truck at 4.5-9.0 ounces per minute, at a vehicle speed of 10-15 miles per hour. This presents a minimal risk to humans, pets and non-target species. Etofenprox presents a low toxicity to birds and dried foliar residues are not harmful to honeybees.
Zenivex is an insecticide that contains synthetic pyrethroids, which emulate naturally occurring insecticides known as pyrethrums, found in chrysanthemum flowers. This pesticide kills mosquitoes effectively yet biodegrades rapidly in the presence of sunlight and/or microorganisms.
Some common pyrethroid products use by consumers include pesticides for common household pests such as ants and wasps; flea and tick shampoos/collars for pets; lice and scabies treatments (shampoos, etc.) for humans; insect repellent clothing, etc. Many pet products contain much higher concentrations of etofenprox, such as commonly used topical flea and tick preventatives.
Comparative Acute Toxicities:
*An LD50 is a measure of toxicity. The longer the LD50 bar, the lower the toxicity. Compared to the active ingredient in other leading mosquito control products, etofenprox, the active ingredient in Zenivex® products, is the least toxic.
It is important to note that in addition to the type of insecticide used is the method that is used for spraying. CMMCP practices Ultra Low Volume (ULV) spraying, which is a method of spraying that allows applicators to control adult mosquitoes using the least amount of pesticide possible. The spray machines are mounted on the back of pickup trucks, and the applicator drives the vehicle in the area to be sprayed. The vehicle operator controls the spray from inside the vehicle, without needing to shut down the spray machine. These application areas are based on public request, request from local officials or after confirmation of virus, and the Field Technician confirms the presence of a mosquito problem by conducting a landing count (landing counts are suspended after confirmation of virus in Mass.).
Generally, there is no need to relocate during mosquito control spraying. The pesticides have been evaluated for this use and found to pose minimal risks to human health and the environment when used according to label directions. Although mosquito control pesticides pose low risks, some people may prefer to avoid or further minimize exposure. Some common sense steps to help reduce possible exposure to pesticides include:
- Listen and watch for announcements about spraying in the local media and remain indoors during the application to the immediate area (please remain inside for 15-20 minutes, or longer at your discretion).
- People who suffer from chemical sensitivities or feel spraying may aggravate a preexisting health condition may consult their physician or local health department and take special measures to avoid exposure.
- Close street-facing windows and turn off the outside setting on window-unit air conditioners when spraying is taking place in the immediate area (you may open windows and activate AC units 15-20 minutes after the application, or longer at your discretion).
- Do not let children play near or behind truck-mounted applicators when they are in use (pets should be brought inside if possible or their cages covered to allow a wider application to be performed).
Yes, any resident can request to be placed on an exclusion list. Exclusion requests may be submitted to the Massachusetts Department of Agricultural Resources (MDAR) at any time during the year by either via first class mail or through an online form. All fields need to be filled out completely by either the owner of the property or the tenant. If submitting a hard copy request it must be sent via first class mail using the form available on MDAR’s website. Once a request is received by MDAR, it will then be transferred to the Mosquito Control District/Project that covers the region in which the property is located, if applicable. Properties to be exempted will be entered into a database designed to track excluded properties, which will be used by Projects during wide-area applications. To register your property as a pesticide exclusion please click this link
To help prevent the spread of WNV and EEE, residents are advised to mosquito-proof their properties. This includes draining or disposing of items that collect water such as rain gutters, drains, unused flowerpots, and wading pools. Regularly change the water in birdbaths and ensure all windows and doors have tightly fitting screens.
Additionally, you may also avoid Mosquito bites by following these simple steps:
Be Aware of Peak Mosquito Hours - The hours from dusk to dawn are peak biting times for many mosquitoes. Consider re-scheduling outdoor activities that occur during evening or early morning. Otherwise, take extra care to use repellent and protective clothing.
Clothing can help reduce mosquito bites - Although it may be difficult to do when it’s hot, wearing long-sleeves, long pants and socks when outdoors will help keep mosquitoes away from your skin. Use mosquito netting on baby carriages or playpens when your baby is outdoors.
Apply Insect Repellent when you go outdoors - Use a repellent with DEET (N, N-diethyl-m-toluamide), permethrin, picaridin (KBR 3023), IR3535 or oil of lemon eucalyptus [p-methane 3, 8-diol (PMD)] according to the instructions on the product label. Reapply as directed, especially after swimming or sweating. DEET products should not be used on infants under two months of age and should be used in concentrations of 30% or less on older children. Oil of lemon eucalyptus should not be used on children under three years of age. Permethrin products are intended for use on items such as clothing, shoes, bed nets and camping gear and should not be applied to skin.
For mor information about Mosquito-borne illness:
https://www.mass.gov/mosquito-borne-diseases
For more information on insect repellent:
https://www.epa.gov/insect-repellents/find-repellent-right-you
September 30, 2024 Report