West Nile Virus Moves Westward, Page 3

Horse Talk

West Nile Virus Moves Westward (continued) -- Page 3

West Nile Virus Workshop to be Presented at 2002 Western States Horse Summit

Rita Schlim, coordinator for the Western States Horse Summit, recently announced, "We're organizing a West Nile Virus (WNV) Workshop for the 2002 Western States Horse Summit, to include leading veterinarians and health officials addressing the concerns of horse owners regarding the WNV.

"The Summit is directed at the twelve western states because there's a pressing concern for horse owners, veterinarians, officials and the public to learn more about the West Nile virus as it moves into our states. We'll be able to present the latest facts and figures on where the virus has spread, plus we want to educate the horse industry on any WNV preventative vaccines and care to given if a horse does come down with the disease.

"We're also asking a representative from Forth Dodge, which received its conditional approval last year, to attend this workshop."

Having been expanded to a two-day agenda, the dates for the 2002 Western States Horse Summit will be May 29-30, followed by the Western States Horse Expo May 31 - June 2. The location will again be the Cal-Expo Fairgrounds, in the same building as the 2001 Summit. Cal-Expo is located just off the Interstate 50 (exit at the Exposition Boulevard ramp) in Sacramento, CA.

Registration packets, additional agenda items and Summit information can be obtained by contacting: WSHS Coordinator Rita Schlim by phone at 510-657-5827 or via email at rschlim@juno.com

Suggested Guidelines for Phased Response to West Nile Virus Surveillance Data

Risk Category	Probability of human outbreak	Definition	Recommended response (Local and regional characteristics may alter the risk level at which specific actions must be taken)
0	None	Off-season; adult vectors inactive; climate unsuitable.	Develop WNV response plan. Secure surveillance and control resources necessary to enable emergency response. Initiate community outreach and public education programs.
1a	Remote	Spring, summer, or fall; areas unlikely to WNV epizootic in 2002 based on lack of previous or current WNV activity in the region.	Responses as in category 0, plus: Conduct entomologic survey (inventory and map mosquito populations; see AM CA and other manuals for guidance); community outreach and public education; avian mortality, human encephalitis/meningitis and equine surveillance.
1b	Low	Spring, summer, or fall; areas anticipating WNV epizootic in 2002 based on previous or current WNV activity in the region; no current surveillance findings indicating WNV.	Response as in category 1a, plus: Source reduction; use larvicides at specific sources identified by entomologic survey and targeted at likely amplifying and bridge vector species; maintain avian mortality vector and virus surveillance; public education emphasizing source reduction.
2	Low	Spring, summer, or fall; areas with initial, sporadic or limited WNV epizootic activity in birds and/or mosquitoes.	Response as in category 1b, plus: Increase larval control and source reduction and public education emphasizing personal protection measures, particularly among the elderly. Enhance human surveillance and activities to further quantify epizootic activity (e.g., mosquito trapping and testing). Consider focal or targeted adult mosquito control if surveillance indicates likely potential for human risk to increase.
3	Moderate	Spring, summer or fall; areas with initial confirmation of WNV in a horse and/or a human, or moderate WNV activity in birds and/or mosquitoes.	Response as in category 2, plus: Strongly consider adult mosquito control of surveillance indicates likely potential for human risk to persist or increase.
4	High	Spring, summer, or fall: quantitative measures indicating WNV epizootic activity as a level suggesting high risk of human infection (for example, high dead bird densities, high mosquito infection rates, multiple positive mosquito species, horse or mammal cases indicating escalating epizootic transmission, or a human case and high levels of epizootic activity) and abundant adult vectors.	Response as in category 3, plus: Expand public information program to include TV, radio, and newspapers (use of repellents, personal protection, continued source reduction, risk communication about adult mosquito control); initiate or continue active surveillance for human cases; implement adult mosquito control program targeted at areas of potential human risk.
5	Outbreak in progress	Multiple confirmed cases in humans; conditions favoring continued transmission to humans (see level 3)	Responses as in category 4, plus: Implement or intensify emergency adult mosquito control program, enhanced risk communication about adult mosquito control, monitor efficacy of spraying on target mosquito populations. If outbreak is widespread and covers multiple jurisdictions, consider wide-spread aerial spraying as per the WNV Emergency Plan.

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Bonnie Davis is a Bay Area resident, free lance writer and horsecamping/trail riding advocate with over 30 years experience. Her stories, articles, and columns have been published in national and international publications such as Western Horseman, Paint Horse Journal, Horse & Horseman, Quarter Horse Journal, Western Side (Italy), Cascade Horseman, California Horse Review, Performance Horse Review, and San Jose Mercury News. Bonnie was a featured speaker at Horsexpo in Sacramento in '99, '00 and '01.