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HomeMy WebLinkAboutCOUNCIL - AGENDA ITEM - 06/22/2004 - DISCUSSION REGARDING THE WEST NILE VIRUS DATE: June 22, 2004 STUDY SESSION ITEM STAFF: Tom Vosburg FORT COLLINS CITY COUNCIL SUBJECT FOR DISCUSSION The purpose of this study session is to consider adoption of the criteria that have been developed by the Larimer Count Board of Health to indicate when West Nile Virus s activity poses a serious enough risk to human health to warrant use of aerosol adulticides. GENERAL DIRECTION SOUGHT AND SPECIFIC QUESTIONS TO BE ANSWERED Staff is seeking the following direction: • Should the City revise its 2004 West Nile Virus program to include the use of aerosol adulticides if and when the trigger criteria are met? If yes; Does Council support the design of the proposed adulticiding program as outlined below? BACKGROUND The City's current plan focuses on education, source reduction, personal protection, and larval control. Council supported this approach at it February Study Session. However, Council also indicated that if the County declares another public health emergency, staff should come back to Council and review the facts of the situation to get further direction. On May 28, the Larimer County Board of Health adopted specific criteria(known as adulticiding triggers) to be used to recommend when local jurisdictions begin the use of adulticides to help prevent a human outbreak of West Nile virus. The intent of these trigger criteria is to predict the onset of a public health emergency. It is not likely that a public health emergency will actually exist at the time the trigger criteria are met. However, it is appropriate for staff to seek direction from Council regarding the City's adoption of the trigger criteria. If the City adopts these trigger criteria, staff will implement the adulticiding triggers administratively, without seeking additional direction from Council. Proposed City of Fort Collins Adulticiding Program If these trigger criteria are adopted by Council for use by the City of Fort Collins, and if the criteria are actually met in 2004, staff proposes that the use of adulticides be carried out in the following manner: June 22, 2004 Page 2 Agent: The City's contractor would use a synthetic permethroid insecticide. Application method: The City would use truck based fogging. Alternatives include aerial application by plane or helicopter. Application Area: The City will conduct targeted spraying of sub-areas of the City, based on criteria data. The City will be divided into about 6 sectors,based on environmental criteria. If data indicates there is sufficient West Nile virus activity within a sector, that sector will be sprayed. While the City's larval control program extends well beyond the City limits, the City proposes to apply adulticides only within the City limits. Public NotiScation: The City will issue a general press release indicating that spraying activity will be taking place in a sector with in a general time frame, weather permitting. In addition to the general notice, the City will set up a subscription automated telephone and e-mail alert system for residents that request specific notification of adulticiding activity in their sector. Application Frequency: Each aduilticiding incident will involve an initial application and a follow up application 4 days later. A final application may be included 10 days later, if trap data indicate it is warranted. Exemptions Criteria: The City will exempt locations from application of adulticides based on the following criteria: •Persons listed on the State chemically sensitive list. •Chemically sensitive businesses •Commercial organic farms or community gardens. The City proposes to not allow individual general residences to opt out of the program as was done last year. Cost per trigger incident: Staff is still developing cost estimates for potential adulticiding scenarios, and will be able to present that information at the study session. ATTACHMENTS Latimer County Board of Health press release re: Adulticiding triggers. • NEWS RELEASE CONTACT: Adrienne LeBailly, Latimer County Dept. of Health and Environment (970) 498-6711 DATE: May 28, 2004 SUBJECT: Board of Health approves mosquito spraying triggers FOR IMMEDIATE RELEASE: The specter of another serious West Nile virus season has prompted early action by the Latimer County Board of Health. "The severity of Colorado's experience with West Nile Virus last year caused the Board of Health to look at triggers for a more timely response to the disease in Latimer County in 2004," said Dr. Adrienne LeBailly, M.D., Director of the Latimer County Department of Health and Environment. "With the warm weather we're experiencing, the West Nile season may start earlier this year," said LeBailly. "We know that infected mosquitoes have survived the winter and • can start a new cycle of infection this spring." Although no confirmed human cases have been reported in Colorado, a positive horse was found in Kit Carson County two weeks ago. The first three human cases of West Nile infection in the U.S. were reported this week, one in New Mexico and two in Arizona. The New Mexico case was occurred in San Juan County, New Mexico, just south of the Durango, Colorado, in the Four Corners area. The Arizona cases were in Maricopa County. The Latimer County Board of Health adopted the following recommendations for spraying or "adulticiding" to control mosquitoes. The measures were approved at the Board of Health meeting on May 20th meeting. Larimer County Board of Health recommended thresholds for adulticiding in urban density areas (based on 2003 Larimer County experience) • West Nile Virus mosquito risk index (average# of Culex females per trap night times infection rate/1000) >= 0.75 and/or • Sudden rise in Larimer County birds submitted that test positive for West Nile Virus • and/or (More) • 1 or more lab-confirmed Larimer County horse West Nile Virus cases close to urban- density population and/or • 1 or more humans with evidence of recent WNV infection (repeatedly positive nucleic amplification tests in blood donors, or positive ELISA IgM/PRNT with compatible clinical illness) "It is important to remember that these are the Board of Health's recommendations. The final decision of whether and how to implement mosquito spraying will be made by each local municipality and by the county for unincorporated areas." LeBailly said. On May 4, the Boulder City Council unanimously approved truck spraying if the local mosquito risk index reaches 0.75. This is the same mosquito threshold adopted by the Larimer County Board of Health. The cities of Loveland and Ft. Collins have been larviciding within their city limits and in a one- to two-mile buffer zone to control mosquito populations since April 2. The county is currently operating 38 light traps to capture and test mosquitoes for West Nile virus. "Although only small numbers of Culex mosquitoes have been trapped, we want to urge people who will be outdoors over the holiday weekend to use repellents," said Larimer County Health Education Supervisor Ann Watson In 2003, Larimer County led the state in West Nile virus infections with 546 cases, 9 fatalities, and 64 serious illnesses. Thirty-two cases of polio-like paralysis were reported in Weld, Boulder and Larimer Counties. Larimer County Department of Health and Environment is actively testing birds that are crows, ravens, magpies, or jays for West Nile virus. LeBailly emphasized that only these birds in the corvid family meet the criteria for testing. The birds must have been dead for less than 48 hours and the exact location of where the birds were found must be available. Color pictures and descriptions of the birds can be found at: www.cdphe.state.co.us/dc/Zoonosis/wnv/CorvidSubmission.pdf For more information on West Nile virus, call the Larimer County information line at: 498-6706. To access the Colorado HelpLine, please call: 1-877-462-2911. The HelpLine is staffed from 7 a.m. to I I p.m., seven days a week. Additional information is available online at: www fightthebitecolorado.com -30-