District Revises Mosquito Management Policy

News Release

District Revises Mosquito Management Policy to Better Address Mosquito-Borne Diseases 

(Feb. 8, 2017) — The Forest Preserve District of DuPage County updated its mosquito management policy to better address potential threats from newly emerging mosquito-borne diseases.

The District will continue to monitor forest preserves for Culex mosquitoes (those most likely to transmit West Nile virus) and to use larvicides made from a natural bacterium to kill Culex larvae if found. It will also continue to post updates at individual preserves and on its website, dupageforest.org, and to share surveillance data with the Illinois Department of Public Health and DuPage County Health Department, which will include the information on its dupagehealth.org/casemaps site.

New to the policy, though, are criteria that must be met before the District will consider using sprays or fogs to kill adult mosquitoes. The previous policy allowed for the use of “adulticides” during “public health emergencies” but did not include specific criteria that must be met before any adulticide treatments take place. Under the revised policy, the District will consider such treatments if:

1. The DuPage County Health Department’s personal protection index for West Nile virus is at level three;

2. Data conclusively shows the source of targeted mosquitoes is on District property;

3. The delivery of sprays or fogs are able to effectively target specific areas; and

4. No other reasonable alternatives to protect the public from an imminent threat of serious illness or death (such as closing a forest preserve) are available.

The District will only use fogs and sprays to kill adult mosquitoes as a last resort. These chemicals dissipate after only 48 hours and can kill any insects they contact, including butterflies, moths, and lightning bugs.

“This policy better defines a comprehensive program to monitor and manage mosquito populations in the preserves, especially under extenuating conditions that threaten public health,” said Forest Preserve District Commissioner Jeff Redick, District 2.

The revised policy also includes information on mosquitoes and public health, mosquito management and ecological integrity, and mosquito management activities currently implemented by the District.

“The revisions further strengthen the policy’s intent to support the District’s mission in protecting and preserving the native biodiversity of DuPage County while also continuing to protect the public health,” said Forest Preserve District of DuPage County President Joe Cantore.

“The policy was updated with background information on newly emerging mosquito-borne diseases and descriptions of the District’s response to these threats within the scope of the District’s mission,” said Tom Velat, Natural Resources ecology coordinator at the District.

The Forest Preserve District of DuPage County has been connecting people to nature for more than 100 years. More than 4 million people visit its 60 forest preserves, 145 miles of trails, five education centers and scores of programs each year. For information, call 630-933-7200 or visit dupageforest.org, where you can also link to the District’s e-newsletter, Facebook, Twitter and Instagram pages.

The Forest Preserve District offers a monthly e-newsletter that includes timely information about projects, programs and events in our DuPage forest preserves. Subscribe to our e-newsletter, and get the latest nature news straight to your inbox.