Somn you can always find a source somewhere to back up what you're preaching. Here's one that differs from yours:
One of the reasons that people give for not drinking raw milk is that they believe it can give them tuberculosis. This is interesting, because the human form of tuberculosis (the one that comes to mind when people say "tuberculosis") is typically an airborne bacteria (tranmitted through coughing). If this form is contracted through milk it likely came from a human worker who contaminated the milk, though transmission is unlikely by these means.
It should also be noted that just because Jimmy drank raw milk, and Jimmy had a positive skin test for tuberculosis exposure, does not mean that Jimmy came in contact with it through the raw milk. A positive skin test for tuberculosis simply means someone has been exposed to certain bacteria (this includes immunization and environmental exposure).
While some people who have had raw milk to drink may produce a positive skin test for tuberculosis, there are reasons other than drinking raw milk that this might occur. It's possible that one could be directly exposed to an infected person or animal infected rather than exposure through milk. There are also other bacteria that are in the same class (Mycobacterium) that can cause cross reactions which result in a positive skin test. The vast majority of the Mycobacterium which can be isolated from raw milk are not disease causing in humans.
One of the few with disease causing potential, called Mycobacterium bovis can cause a disease similar to tuberculosis in humans, and this is the bacterium that most health-related literature is referring to when "tuberculosis" is contracted from animals. The common recommendation among most health organizations to prevent infection is to avoid unpasteurized milk products, but rarely, if ever, can the reported cases of the disease be conclusively linked to dairy. Consider the findings of the Wellington Hospital in New Zealand. In reference to Mycobacterium bovis they found...
that an average of 7.2% of cases of tuberculosis were caused by this organism (Brett and Humble, 1991). The most common organ affected was the lung (pulmonary tuberculosis) which suggests that the disease was not caused by contaminated meat or milk. Instead it was suggested that the primary source may be exposure to animals in regions of New Zealand where M. bovis is endemic in cattle, deer and feral animals.
In almost all cases, people who test positive have been directly in contact with infected animals or with people who have.
Additional support for the difficulty in contracting M. bovis comes from a recent study from the U.K.
Epidemiol Infect. 2001 Aug;127(1):87-0
Results of follow-up of human contacts of bovine tuberculosis in cattle during 1993-7 in North Staffordshire.
Smith GE, Cawthorne D, Jarvis R, Synnott MB, Cooper R, Hampton C, Allen M.
North Staffordshire Health Authority, Heron House, Stoke-on-Trent, UK.
The purpose of the study was to describe the results of follow up of human contacts of bovine tuberculosis. The bovine tuberculosis cases occurred on farms in North Staffordshire between 1993 and 1997. A total of 162 people were identified as having close contact with cattle diagnosed as having bovine tuberculosis, or who had drunk unpasteurized milk from a herd with bovine tuberculosis. A retrospective review of chest clinic notes was performed. One hundred and thirty-eight people attended for follow up, and Heaf test results, necessity for chest X-ray and further clinical follow-up are described. No case of human Mycobacterium bovis infection was identified. It is suggested that follow-up of human contacts is limited to those with close contact with herds who have bovine tuberculosis and cattle with visible pulmonary lesions or evidence of udder infection. Children on the farms with affected cattle should also be offered BCG in advance of the routine school's programme.
In this case there were 162 people with known close contact exposure to infected cattle and not a single case of human infection occurred. Interestingly the immunization that is recommended in the article is an attenuated strain of M. bovis which is given to people in many parts of the world as one of the standard immunizations.
A more recent outbreak in cattle in California was reported by the CDC:
Int J Tuberc Lung Dis.2005 Jul;9(7):809-13.
Investigation of human contacts: a Mycobacterium bovis outbreak among cattle at a California dairy.
Winthrop KL, Scott J, Brown D, Jay MT, Rios R, Mase S, Richardson D, Edmonson A, MacLean M, Flood J.
Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
[email protected]
BACKGROUND: In May 2002, a Mycobacterium bovis outbreak occurred among cattle at a California dairy. We investigated to determine whether persons were infected after working with the cattle or drinking their raw milk. METHODS: We identified persons with potential contact with infected cattle, including dairy workers, their family members, and slaughterhouse workers. Persons were given a tuberculin skin test (TST), and their occupational and milk-drinking habits were recorded. RESULTS: Of 88 potential contacts, 78 (90%) were given a TST; 33 (43%) had positive TST results, of whom 32 were Mexican-born (RR 15.8, 95%CI 2.3-108.8). No persons had active tuberculosis. Eighteen (72%) dairy workers, 11 (27%) family members, and four (33%) slaughterhouse workers had positive TST results. After adjusting for Mexican-birth and age, dairy workers were no more likely to have positive TST results than others (adjusted RR 1.2, 95%CI 0.6-2.1). Forty-one (62%) dairy staff and their family members drank raw milk from the dairy; 21 (51%) had positive TST results and were Mexican-born. All 13 US-born raw milk drinkers had negative TST results. CONCLUSION: A high prevalence of positive TST results was documented among workers at the affected dairy, although results were not independently associated with contact with infected cattle or milk products. Further assessment of California dairy workers should be considered.
In this case they showed that no one had active tuberculosis, and even the workers at the dairy who were directly exposed to the infected cattle had no greater risk of having a positive skin test than the other people in the study and all of the people who tested positive were foreign-born. None of the people had active tuberculosis, and not one single US-born person (people with no prior exposure to the bacteria) who drank the raw milk had a positive skin test.
Other related bacteria have been shown to survive pasteurization:
Acta Vet Scand 2003;44(3-4):261-6.
Mycobacterium paratuberculosis and milk.
Grant IR.
Department of Food Science (Microbiology), Queen's University, Belfast, N. Ireland, UK.
The possibility that milk from cattle with Johne's disease could be a potential vehicle of transmission of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) to humans has been the focus of a UK government-funded research programme at Queen's University, Belfast since 1993. The main findings of this research programme are reported and practical advice about the most appropriate methods for the isolation/detection of this organism in milk is given. The findings of several milk surveys during which optimised sensitive detection methods were employed (decontamination with 0.75% cetyl pyridinium chloride for 5 h prior to culture and a novel immunomagnetic PCR technique) have revealed that detectable levels of M. paratuberculosis are present in bulked raw cows' milk in the UK at both the farm level and at dairy processing plants prior to pasteurisation. Furthermore, results of three different experimental approaches to assess the effect of pasteurisation time/temperature conditions on the viability of M. paratuberculosis (laboratory pasteurisation studies, a national survey of commercially pasteurised milk, and processing of naturally infected milk through commercial-scale pasteurising plant) provide firm evidence that this organism is capable of surviving commercial milk pasteurisation on occasion. Hence, both raw and pasteurised cows' milk are potential vehicles of transmission of M. paratuberculosis to humans.
Clearly this provides no argument in favor of pasteurization, since often these organisms are viable following the process. These are but a few of the most recent examples of the ridiculousness of the campaign which continues against raw milk in much of the country.
