past July, Rep. Denny Rehberg (R-Montana) based his opposition
to Rep. Nick Rahall’s (D-West Virginia) amendment to
the Interior Appropriations bill banning the use of federal
monies by NPS and USFS for the killing of Yellowstone bison
on the assertion that brucellosis is a major bioterrorism
threat and human health risk.
Congressman Rehberg stated “There are people all over
this country and in the State of Montana that carry undulant
fever, brucellosis; and they get it from these animals.”
The truth is that there has not been a reported case of undulant
fever in Montana since 1995, and that there have been only
46 reported cases in Montana since 1957 none of which resulted
from contact with wild bison. According the Centers for Disease
Control and Prevention (CDC), cases of human brucellosis in
the United States are rare with around 100 reported cases
a year, again, none resulting from contact with wild bison.
Representative Rehberg also cited a document outlining biological
agents that “have the potential to pose a severe threat
to public health and safety”.
In the CDC’s interim rule for meeting with the conditions
of The Public Health Security and Bioterrorism Preparedness
and Response Act of 2002, the section addressing overlap select
agents and toxins (42 CFR 73.5), does include seven bacteria
species in an alphabetical list one of which is brucella abortus.
However, according to Appendix 1 of the Public Health Assessment
of Potential Biological Terrorism Agents prepared by the CDC,
brucellosis is a category B bacterium while Anthrax, a much
more serious bacteria according to the document, is placed
in category A. Further, in the CDC’s Brucellosis overview,
brucella meletensis and brucella suis are considered much
more important than brucella abortus in terms of public health
security and preparedness. The fact of the matter is that
wild bison, potentially infected with brucella abortus, do
not pose a human health danger.
Representative Rehberg’s contention that brucella abortus
in wild bison poses a “herd health danger” to
cattle is also vastly overstated.
Two effective vaccines currently exist for brucella abortus
for domestic cattle, Strain 19 and RB51. In Grand Teton National
Park, domestic cattle and potentially infected wild bison
have commingled for over 50 years without a single instance
of brucellosis transmission. The simple fact is that under
natural conditions with vaccinated cattle, wild bison pose
virtually no risk of brucellosis transmission. Further, The
National Research Council’s study titled, Brucellosis
in the Greater Yellowstone Area, concludes, ”the current
risk of transmission from YNP bison to cattle is low.”
The study also states that there has never been a documented
case of transmission from wild bison to cattle.
In addition to the low risk of transmission from wild bison,
many other species of wildlife in the Greater Yellowstone
area are potentially infected with brucellosis. These include
elk, deer, moose, bighorn sheep, coyote, wolf, muskrat, and
beaver. None of these species are subject to the harsh management
practices of the Montana Department of Livestock and all are
allowed unfettered access into Montana from Yellowstone National
of Montana, Public Health Records. “Human Brucella Cases,
Montana 1957 to 7/2000”
Centers for Disease Control and Prevention. Summary of notifiable
diseases, United States, 1996. MMWR 1996;45(53): [p.26].
Centers for Disease Control and Prevention, Department of
Health and Human Services. Interim final rule. 42 CFR Part
73.5, Possession, Use, and Transfer of Select Agents and Toxins,
United States, 2002
Centers for Disease Control and Prevention, Public Health
Assessment of Potential Biological Terrorism Agents. Lisa
D. Rotz, Ali S. Khan, Scott R. Lillibridge, Stephen M. Ostroff,
and James M. Hughes, Atlanta, Georgia, USA. 2002.
Montana Dept. of Fish, Wildlife and Parks, Brucellosis in
the Greater Yellowstone Area. www.fwp.state.mt.us
The National Research Council, Brucellosis in the Greater
Yellowstone Area. National Academy of Sciences Press, Washington,
DC. 1998 p. 80,45.