Bovine TBC transmissible through raw milk to humans

Spreading of the bovine TBC in the Allgäu causes concern to the authorities

02/07/2013

For a long time, Germany was considered to be free from bovine tuberculosis (bovine TBC), but after several infected animals were discovered in the Allgäu region, fears of a renewed spread are growing. Since people can also infect raw milk with bovine TBC, the authorities are particularly sensitized. Comprehensive safety precautions were taken, companies suspected of being closed and possibly infected animals killed.

According to the farmers, the official action in the fight against bovine TB is at least partially overdrawn. Here healthy animals would be killed without a legal basis and farm closures carried out to protect the financial interests of dairies, which otherwise would have to take the milk, complained Johannes Wachinger, spokesman for the „Community of interests for healthy animals“ (IttG). Allegations that meet at the Oberallgäuer Landratsamt on little understanding, especially according to the announcement of the district on „Initiative of District Administrator Kaiser put an emergency order of the Federal Ministry of Food, Agriculture and Consumer Protection into force“ was the „the current bovine TB Regulation for the next six months“ changes. Thus, the blocking periods for the farms were significantly shortened and the cattle with unclear test result no longer necessarily be culled, but it can be done after 42 days, a new test.

Bovine TBC also transmissible to humans
Tuberculosis can be a bacterial infectious disease in both humans and animals. Although the runs „human“ Tuberculosis is largely independent of animals, that is, humans usually contract humans, but bovine TB can also be transmitted to humans. Responsible for tuberculosis in humans is the pathogen Mykobacterium tuberculosis, for bovine TBC the pathogen Mykobacterium Caprae. The latter work „less infectious in humans than in cattle“, why the risk of infection is very low, reports the district of Oberallgäu. However, be „a contagion is not completely excluded.“ So far, however, no case of a proven infection of people with bovine tuberculosis was detected in the district of Oberallgäu. There is „Although currently two cases in which immunoassays yielded the result that farmers from the Upper Allgäu at some point in their lives with any mycobacteria have come into contact - but that does not mean that there is a connection with the current bovine TB community“, so the official position. As a precaution, the patients should be treated with appropriate antibiotics.

Stocks at more than 1,300 farms controlled on bovine TBC
The situation is particularly difficult for the dairy farmers in the Allgäu, as their milk is usually processed into raw milk products such as the Allgäu Emmentaler or Allgäuer Bergkäse and the cattle TBC could theoretically be transferred in this way. For the benefit of consumers, the reintroduced screening of bovine herds makes perfect sense. „Because only if at all examined, infected animals can be detected early - without being dependent on chance finds at the slaughter“, reports the district of Oberallgäu. By the end of the year, according to official statements, all 2,043 cattle-rearing farms in the district and in the city of Kempten are to be inspected. To date, 1,356 beef farms have been studied, of which 1,335 „recognized free of tuberculosis“ be, the district continues. 21 farms are currently still blocked because of suspected infection with bovine tuberculosis for the time being.

Possible tuberculosis infections due to red deer
Altogether 52,136 of the approximately 90,000 cattle in Oberallgäu have been tested in the district of Oberallgäu and 785 animals have been killed. There were almost always only individual animals affected, „which suggests that the animals are detected on the one hand in an early stage of infection and on the other hand have been infected outside the farm“, so the official message. Rotwild is considered as a possible source of infection, as many dairy farmers graze their cattle on the 600 Oberallgäu Alps in summer. During the Almsaison the cattle come into contact with the excrements of the red deer and use at least partially the same feeding places. Salt licks are also gratefully accepted by the deer. In this way pathogens from the wild population can easily pass on the dairy herd. „In deer, 479 of the animals examined in the hunting year of 2012 had 21 infected with the same pathogen as livestock (Mykobacterium caprae)“, reports the district of Oberallgäu.

Provision to avoid TBC transmission
Although the alpine season, as reported by the district may take place as usual, but the farmers should stick to some recommendations for the alpine pasture. For example, the „free feeding on alpine meadows is to be avoided as a precautionary measure; grazing of red deer guards is discouraged“ and „Salt feeding should be done so that both species can not reach the same feeding at the same time.“ Also, farmers would have to be aware of the fact that „especially in shady locations without direct sunlight (UV), the pathogen can keep longer on faeces or food leftovers“, so the message of the district Oberallgäu. It is important to minimize the opportunities for contact between hoofed game and cattle as much as possible.

Pasteurized milk can be consumed without hesitation
The milk from stocks with cattle TBC „can be recycled after previous pasteurisation“ and the generated from this „Food is also freely tradable on the European market“, explains the administrative district Oberallgäu in his press release. If raw milk is sold directly from the farm, the farmer is generally required by law to indicate by a clearly visible sign that the milk is to be boiled before consumption. For the production of raw milk cheese, which is widespread in the Allgäu, it is only allowed „Used in stocks that are considered to be officially tuberculosis-free“, so the official message. For the farmers of the Allgäu, the spread of bovine TBC could therefore quickly reach a life-threatening extent. (Fp)

Picture credits: uschi trio