Brucellosis confirmed in Sublette County
Wyoming State Veterinarian Dr. Jim Logan has been notified that cultures are positive for field strain Brucella abortus (Brucellosis) on cows from one Sublette County cattle herd. Results were received on December 9, 2015 from the Wyoming State Veterinary Laboratory (WSVL) in Laramie.
Logan, with concurrence of USDA-APHIS, has designated the herd from which the reactor cows originated as “Brucellosis affected” as of Dec. 9.
Cattle from the Sublette County herd, located within Wyoming’s Designated Surveillance Area (DSA), were positive to blood tests at the WSVL and the National Veterinary Services Laboratory (NVSL) in Ames, Iowa. Specified cattle from the DSA are required to be tested within 30 days prior to change of ownership or movement from counties within the DSA. The herd was quarantined on November 19 when preliminary tests were suspicious for Brucellosis. The quarantine will remain in effect until the herd has undergone three consecutive, negative, whole-herd tests after any reactors have been removed from the herd.
Whole-herd testing was conducted on the “affected” herd on Dec. 3 and 4, and additional reactor animals were identified. There are five contact herds also under quarantine for herd testing. The contact herds will be released from quarantine if their herd tests are negative.
The testing is being conducted as a cooperative effort between herd owners, Wyoming Livestock Board (WLSB) personnel, and private veterinary practitioners. Epidemiologic interviews with herd owners are ongoing and quarantine herd plans will be developed with each herd owner associated with the case. Epidemiologic tracing will continue in the upcoming weeks by WLSB and APHIS personnel.
“Finding Brucellosis in our DSA is not an unexpected event,” said Logan. “We have a reservoir of Brucellosis in wildlife in northwest Wyoming that occasionally will spill over into cattle. Our producers do a good job of mitigating their risks and trying to prevent Brucellosis in their cattle herds. This situation illustrates the value and effectiveness of our surveillance program in Wyoming. We believe we found this case before the disease spread to other areas, and we are dealing with it appropriately. At this time, we do not have verification that this case has resulted from wildlife exposure, but that is very likely. The epidemiological investigation will give us an answer with time. All of Wyoming’s cases of Brucellosis, from 2003 to 2011, have been verified as elk source exposure.”
Logan would like to thank all the producers and veterinarians in the area for their good cooperation in a very difficult situation. “We expect to complete the initial stages of this response by the end of December with follow-up testing to occur in the ensuing months.”
The WLSB also has one Park County herd under quarantine for a Brucellosis case verified in mid-November. That herd has since undergone one negative herd test. The only contact herd in this case has been released from quarantine, having tested clean on a whole-herd test.
For further information, please contact Logan at 307-857-4140 or 307- 421-1682.
–Wyoming Livestock Board