CL & Drinking Milk

where I want to · #41 02/28/12, 01:38 PM

The blood tests are not reliably inaccurate. They have a certain percentage of false negatives or positives depending on the test type (and the quality of the lab involved.) But that level of error is not large.
I have been told that humans are a dead end host for CL- that a local abscess can form in a cut but that it won't spread.
I don't know the truth as it is so rare for CL to spread to a human- only Australia has any kind of records on this and those are not recent as they have had a widespread vaccination program for awhile and that has reduced the incidence of human involvement.
But I would treat it very carefully as I had a goat with a very virulent case of CL and developed abscesses in a finger that had a small cut at the time. It has NEVER cultured for CL- it has never culture for anything. But after several surgeries that have not eliminated the problem, I am super cautious.

Added- there is an ELISA test for CL.

Alice In TX/MO · #42 02/28/12, 05:28 PM

Here's an abstract with a mention of using an Elisa test for CL.

http://www.ncbi.nlm.nih.gov/pubmed/20305291

Creamers · #43 02/28/12, 11:20 PM

WADDL's info on CL as of 2011

"6. What does a positive or negative blood test mean?
The serology test is best used as a screen to find out if a herd or flock has been infected, rather than to diagnose an individual animal with CL. An individual animal positive CL serology test does not necessarily mean an animal is infected with C. pseudotuberculosis or has CL. Furthermore, the test cannot distinguish between natural exposure and vaccination, therefore vaccinated herds may test positive. Nonetheless, herds with a high proportion of animals with positive SHI tests are very likely to contain C. pseudotuberculosis infected animals, whereas herds with few or no SHI positive animals may represent little risk of CL introduction. Animals within a positive herd are at risk for developing abscesses, and the herd should be monitored for visible subcutaneous abscesses. Titers in an individual animal do not correlate well with risk of abscess development.
A negative serologic result on an individual animal does not definitively rule out infection by C. pseudotuberculosis. The confidence in a negative result is enhanced if most or all herd mates also test negative."

"10. Is it okay to drink raw milk containing C. pseudotuberculosis?
Human infections with this bacterium are rare, but when found are often associated with occupational exposure to sheep and goats. Drinking raw milk is a potential source of human infection. There are other more serious zoonotic pathogens (infectious agents transmitted from animals to humans) that are regularly transmitted to humans through raw milk. Consult your veterinarian regarding the public health hazards of consuming raw milk."

If you have further questions, please call the main WADDL office at 509-595-9696 and ask to speak with the consulting microbiologist. - the site says

http://www.vetmed.wsu.edu/depts_waddl/FAQ/cl.aspx