SCIENCE IN THE NEWS DAILY
Bovine TB Disguised by Liver Fluke
from Nature News
Bovine tuberculosis (bTB) could be spreading across Britain because the most widely used test for the disease is ineffective when cattle are infected with a common liver parasite.
The liver fluke Fasciola hepatica was already known to affect the standard skin test for bTB, but it was unclear whether the fluke stopped the disease developing or merely hid the symptoms. A study published today in Nature Communications suggests that the latter is more likely, and that the effect is significant. It estimates that around a third of bTB cases in England and Wales are undiagnosed because the test is less sensitive in cattle infected with the fluke.
Researchers tested milk from dairy herds across England and Wales for antibodies against F. hepatica, an indication of infection, and added the data to an existing model of bTB transmission. If they assumed that a fluke infection inhibited bTB detection, they achieved a closer match between the model and actual bTB detection rates. The authors suggest that the fluke may alter the production by T lymphocytes--key cells in the immune system--of the protein interferon-?, which is crucial to a genuine result in both the skin test and the second most common test for bTB, the interferon-? release assay (IGRA) blood test.
Subscribe to Our Content!
Visit our RSS Feeds page to choose among 13 customized feeds, or create a free My AmSci account to request an email notice whenever a specified author, department or discipline appears online.
A free daily summary of the latest news in scientific research. Each story is summarized concisely and linked directly to the original source for further reading.
An early peek at each new issue, with descriptions of feature articles, columns,
and more. Every other issue contains links to everything in the latest issue's table of contents.
News of book reviews published in
and around the web, as well as other noteworthy happenings in the world of science books.
To sign up for automatic emails of the
Update and Scientists' Nightstand issues, create an
online profile, then sign up in the
My AmSci area.
Science in the Media
Magazines and Web Sites:
The Science-Media Intersection: