Updated West Nile Virus Information (Cambridge Public Health Department) – Aug 29, 2012
West Nile coverage on Cambridge Public Health Department website: www.cambridgepublichealth.org/wnv
The recently added section on Local Response with an update of the City’s efforts can be found at:
www.cambridgepublichealth.org/services/environmental-health/mosquito-borne-diseases/local_response.php
Aug 28, 2012
The Cambridge Public Health Department leads the city’s response to the risks posed by West Nile virus and other mosquito-borne diseases.
West Nile virus was first detected in birds and mosquitoes in Massachusetts in 2000. Starting that year, Cambridge established a phased response to the threat of West Nile virus that emphasizes reduction of mosquito breeding habitats (e.g., wading pools, old tires, clogged rain gutters), personal protection, and education.
The Public Health Department works closely with the city’s Department of Public Works and Inspectional Services Department to reduce mosquito-borne risk during the mosquito season (May through early November).
Mosquito control actions taken as of Aug. 28, 2012:
The use of mosquito larvicides is generally considered more effective than spraying for adult mosquitoes, since it stops mosquitoes from breeding. Cambridge larviciding activities include:
- The East Middlesex Mosquito Control Project (through an agreement with the City of Cambridge), has treated the city’s 5,140 municipal storm drains with a larvicide that prevents mosquito larvae from reaching maturity.
- The East Middlesex Mosquito Control Project has applied hand-held non-chemical larvicide to treat areas that are considered prime habitats for mosquito breeding. The treated areas include the Fresh Pond Reservation, Danehy Park, the Fresh Pond Golf Course, Magazine Beach, and the wetland areas along the Little River near the Alewife Brook.
- Both universities are currently treating storm drains on their own property or working with the city and the East Middlesex Mosquito Control Project to arrange for treatment by the end of August.
The Cambridge Public Health Department is not recommending spraying for adult mosquitoes at this time, but an active review of most effective practices used in other urban communities is underway.
- This decision is based on multiple factors, including research demonstrating that “truck spraying” in densely built urban communities, such as Cambridge, may be of limited effectiveness because buildings and higher trees prevent spray from reaching the most likely mosquito habitat in the canopies of trees. Further evidence of risk to humans is being carefully monitored and will be an important factor in the decision to use truck-based spray during the current season.
- The health department has been informed by the mosquito control agency serving Cambridge that spraying Russell Field or Danehy Park will not be carried out because these are open fields not bordered by thick vegetation, and thus spraying would likely not be effective in reducing the adult mosquito population.
- Wetlands near both Russell Field and Danehy Park have already been treated during the summer with non-chemical larvicides (as mandated by law) to reduce the adult population of wetlands mosquitoes. It is important to note that typical wetlands mosquitoes, while annoying, are not the carriers of West Nile virus in urban areas like Cambridge.
More About Larviciding
- Every summer, the East Middlesex Mosquito Control Project (EMMCP) treats the city’s municipal storm drains with a larvicidal agent that prevents mosquitoes from breeding. The treatment rotates between a chemical agent and a bacteriological agent to reduce the risk of natural resistance in mosquito larvae.
- The EMMCP, through an agreement with the City of Cambridge, applies hand-held non-chemical larvicide to treat areas that are considered prime habitats for mosquito breeding. The treated areas typically include the Fresh Pond Reservation, a small portion of Danehy Park, and the wetland areas along the Little River near the Alewife Brook. EEMCP also maintains several surveillance mosquito trapping stations in Cambridge.
Public Information about West Nile Virus in Cambridge
- The Cambridge Public Health Department website offers information about mosquito-borne illnesses, including news updates, disease fact sheets, prevention tips, and links to relevant state and national public health agencies.
- The Cambridge Public Health Department maintains an e-mail list to deliver periodic updates about West Nile virus and eastern equine encephalitis to subscribers. The WNV Listserv is a service available to all community members. Please type “subscribe” in subject header when requesting to be put on this list.
- The Cambridge Public Health Department assists the Cambridge Public Schools in communicating with parents and establishing an appropriate policy for outdoor athletic events that are held from late August until early October, or the first frost (periods of heightened risk).
Eliminating Stagnant Water
- The Cambridge Public Health Department, the Department of Public Works, and the Inspectional Services Department respond to calls reporting stagnant water and other potential mosquito habitats on private and public property. The division of responsibilities for responding to these calls is as follows: DPW is charged with addressing standing water on public property, Inspectional Services is responsible for standing water on construction sites and commercial property, and the public health department follows up on calls about standing water on private property.
Revised on August 28, 2012