USDA - E. Coli Test

[Rockwell.David@epamail.epa.gov]

----- Forwarded by David Rockwell/R5/USEPA/US on 03/20/02 10:15 AM -----

USDA NEWS

~~ARS Developing Test for E.coli~~USDA scientists have developed a
rapid,
easy-to-use test to detect and count E. coli O157:H7 bacteria in natural
and
constructed bodies of water. Agricultural Research Service (ARS)
microbiologists Dan Shelton and Jeff Karns in the Animal Waste Pathogen
Laboratory, Beltsville, Md., developed the test, which uses magnetic
beads
to detect the pathogen. The magnetic beads are coated with anti-E. coli
monoclonal antibodies that bind to the bacteria, making it possible to
count
the bacteria. Current testing methods are designed only to detect the
bacteria, but not to measure how many are present. The number of E. coli
bacteria present is crucial information since the levels that cause
infection can vary from person to person, depending on the person's
health
status. Also, the new method makes it possible to detect E. coli in
water
samples in a day or less, compared with traditional testing that can
take up
to four days to complete.  If this test proves to be accurate and
selective,
it should allow for detection of E. coli in a variety of liquid samples,
such as swimming pools and other recreational waters.

----- Forwarded by Roger Nanney/R5/USEPA/US on 03/19/2002 11:52 AM -----


USDA Finds Igen-Based E. Coli Test Is Effective

By Terence Chea
Washington Post Staff Writer
Friday, July 6, 2001; Page E05

Scientists at the Department of Agriculture say they have developed an
effective water-safety test based on technology from
Igen International Inc., boosting the Gaithersburg company's plans to
enter the market for environmental tests.

USDA researchers found the test to be more effective than other methods
at detecting very small amounts of the bacterium E.
coli O157, which can cause serious gastrointestinal illness, according
to a report in the July issue of the journal Applied and
Environmental Microbiology.

The test was designed with Igen's Origen technology, which uses
light-emitting compounds to detect biological substances.
Currently, Origen-based tests are used to diagnose disease, develop
pharmaceuticals, test blood samples and detect bacteria in
food.

Richard J. Massey, Igen's president and chief operating officer, said in
a prepared statement that the study "suggests that new
guidelines for testing water could be implemented based on Origen
technology, significantly expanding the market for Igen's
products."

Igen is stepping up efforts to market its PathIgen test, which can be
used to detect a variety of microorganisms. The company
estimates the worldwide market for such tests to be worth about $2
billion annually.

The company recently has announced other studies that demonstrate the
tests' advantages over existing testing techniques. For
example, Igen said a recent study showed that PathIgen was the only test
that detected 100 percent of E. coli. The company
also said the British government ordered the test to evaluate its
ability to detect bacteria in livestock.

                                 © 2001 The Washington Post Company