BOVINE TUBERCULOSIS, BOVINE - USA (02): (MICHIGAN)

A ProMED-mail postProMED-mail is a program of theInternational Society for Infectious Diseases Date: 23 Mar 2010Source: Up North Live.com [edited] An Emmet County cow is found positive for bovine tuberculosis (TB), now all cattle herds within a 10-mile radius of the farm will have to be tested within 6 months. Routine bovine tuberculosis (TB) surveillance testing, conducted by the Michigan Department of Agriculture (MDA), found a bovine TB positive herd in Emmet County in Northern Lower Michigan's Modified Accredited Advanced Zone (MAAZ). "If we test all the cattle herds within a 10-mile radius circle around the positive herd, and they are negative, the status of the MAAZ will not be impacted, as there would have to be at least 3 positive cattle herds in the zone in a year, for the status to drop," said Dr. James Averill, MDA's bovine TB project coordinator. "There are 67 farms that will be contacted and informed of the need to test for bovine TB." An informational meeting for Emmet County producers is scheduled for Wed 21 Apr 2010, from 7-9 p.m. at the West Traverse Township Hall, 8001 M-119, Harbor Springs, Michigan. On 4 Jan 2010, the MDA, in coordination with the U.S. Department of Agriculture (USDA), expanded the MAAZ to include Antrim, Charlevoix, Cheboygan, Crawford, Emmet, and Otsego counties. Michigan rules divided the MAAZ into subzones, which are areas with decreasing prevalence of bovine TB in both cattle and wildlife. Emmet County is in Subzone 1 of the MAAZ. In this Subzone, cattle producers test their herd every 1, 2, or 3 years, depending upon the type of cattle they sell. "All cattle and bison farms within the 10-mile circle of the positive herd will be tested within the next 6 months and then revert back to their normal testing schedule if they all come up negative," said Averill. "This testing will protect all Michigan cattlemen from the small chance of buying TB infected cattle. The ultimate goal is to return bovine TB Free status to the entire state -- and we want to do everything we can to ensure we reach that goal." Although testing is an effective way to prevent bovine TB from spreading to other herds, there is a continued presence of TB in the wild white tailed deer population in Northern Lower Michigan. To reduce the risk of a herd getting infected from surrounding deer, producers can put practices in place and become verified in the Wildlife Risk Mitigation program. Cattle farmers in Subzone 1 who obtain this status are at lower risk, and can move cattle more freely than those who do not. While infection can occur by nose-to-nose direct contact, infection is much more likely to occur when cattle feed is contaminated by infected deer [saliva, nasal droplets, etc]. Beef and dairy farmers can decrease the risk of exposing their cattle to bovine TB by limiting cattle-to-deer contact and protecting cattle feed from deer with wildlife risk mitigation tools. MDA's Director Don Koivisto signed an updated Zoning Order on 23 Mar 2010, clarifying the testing requirements for Michigan cattle from farms in the MAAZ Subzone 1 or the MAAZ that move without wildlife risk mitigation plans. For complete details, go to the Emerging Diseases website by clicking on The Emmet County herd is the 2nd TB positive herd identified in Michigan in 2010. A beef herd in Alcona County, which is in the MAAZ, was found to be infected with bovine TB in early March [2010]. Since the bovine TB eradication effort began, all of Michigan's one million cattle have been tested for the disease. Since 1998, the MDA and the USDA have detected 48 cattle herds and 5 privately owned cervid operations in Michigan's MAAZ with bovine TB positive animals on the premises -- either the premises have been depopulated or the herd was quarantined and placed under a test-and-remove program. To date, the Michigan Department of Natural Resources and Environment (DNRE) has tested more than 184 120 wild white-tailed deer, with 668 testing positive for bovine TB. Strategies adopted by the DNRE to reduce bovine TB in the wild white-tailed deer have reduced the prevalence rate of the disease from the high in 1995 of 4.9 percent to 1.9 percent in 2009. The disease prevalence in wild white-tailed deer has flattened in the last few years, and the risk of bovine TB positive deer infecting cattle persists. --Communicated by:ProMED-mail [Bovine tuberculosis is caused by _Mycobacteirum bovis_. While there are other _Mycobactirium_ spp, _M. bovis_ and _M. tuberculosis_ are among the most important, as these tend to move between animals and people. Disease caused by mycobacteria often develop very slowly and may take months to years to develop. These bacteria grow very slowly and only replicate every 12-20 hours. While the pathogenic species (those which can cause disease) such as _M. tuberculosis_ and _M. bovis_ can infect a human or an animal, often the individual does not know that he has been infected. In humans, those infected but without active disease can be treated to prevent disease from occurring. To prevent other animals from being infected, a diseased animal must be culled from the herd. The disease primarily affects the respiratory tract but can also spread to other parts of the body. The primary route of transmission is the exchange of respiratory secretions between infected and uninfected animals. This can be achieved through nose-to-nose contact or by the inhalation of aerosol droplets that have been exhaled by an infected animal. Animals may also become infected with _M. bovis_ by ingesting the bacteria. This could occur by ingesting feeds that have been contaminated with _M. bovis_ by other infected animals. Carnivores may become infected with bovine TB by eating infected carcasses. Various factors affect the efficiency in which _M. bovis_ is spread within a cattle herd. The number of infected animals shedding the organism, as well as the number of susceptible animals present within a herd can have an impact on the transmission of the bacteria. For example, the more animals within a herd that are shedding _M. bovis_, the greater the chance of an uninfected animal coming into contact with an infected animal. The animal density of a herd also influences the efficiency of _M. bovis_ transmission. Transmission of _M. bovis_ among animals housed in confinement facilities may be greater because of close contact. Cattle infected with bovine TB may shed bacteria in their feces, urine and milk, but these are felt to be a minor source of bacterial transmission. Environmental contamination with _M. bovis_ may play a role in the spread of bovine TB. Survival of _M. bovis_ in the environment is primarily affected by exposure to sunlight. Reports on the length of survival of _M. bovis_ vary from 18-332 days at temperatures ranging from 54-75 F. Under laboratory conditions, _M. bovis_ has been isolated for up to 8 weeks from various feeds kept at 75 F and 14 weeks from various feeds kept at 32 F. However, under field conditions, it is difficult to isolate _M. bovis_ from pastures grazed by animals known to be infected with bovine TB. Portions of this comment have been extracted from:- Mod.TG] [The interactive HealthMap/ProMED map for Michigan is available at: - CopyEd.EJP] [see also:Bovine tuberculosis, bovine - USA: (SD) 20100107.00652005----Tuberculosis, bovine, human ex cervid - USA (MI) 20050112.01022003----Tuberculosis, bovine - USA (MI) (02) 20030606.1392Tuberculosis, bovine - USA (MI) 20030217.04152002----Tuberculosis, bovine - USA (MI) 20021208.60162001----Tuberculosis, bovine - USA (Michigan) 20001001.16952000----Tuberculosis, bovine, deer - USA (Michigan) 20000426.06301999----Tuberculosis, bovine - USA (Michigan) (02) 19990522.0840Tuberculosis, bovine - USA (Michigan) (02) 19990519.0822Tuberculosis, bovine - USA (Michigan) 19990517.0803Tuberculosis, bovine - USA (Michigan) 19990110.0033Tuberculosis, bovine - USA (Michigan) 19980923.1899].....................................sb/tg/ejp/dk *##########################################################*************************************************************ProMED-mail makes every effort to verify the reports thatare posted, but the accuracy and completeness of theinformation, and of any statements or opinions basedthereon, are not guaranteed. The reader assumes all risks inusing information posted or archived by ProMED-mail. ISIDand its associated service providers shall not be heldresponsible for errors or omissions or held liable for anydamages incurred as a result of use or reliance upon postedor archived material.************************************************************Donate to ProMED-mail. Details available at:************************************************************Visit ProMED-mail's web site at .Send all items for posting to: promed@promedmail.org(NOT to an individual moderator). If you do not give yourfull name and affiliation, it may not be posted. Sendcommands to subscribe/unsubscribe, get archives, help,etc. to: majordomo@promedmail.org. For assistance from ahuman being send mail to: owner-promed@promedmail.org.########################################################################################################################