New Tests Accurately Detect
By Kathryn Barry
July 13, 2000
Horse owners who transport their
animals internationally for equestrian competitions may soon have an easier
time ensuring their horses are healthy, thanks to new tests for piroplasmosis.
The United States is free of this tick-borne disease, also known as equine
babesiosis. To keep the disease from infecting American animals, horses
transported here for races, shows and other competitions must be certified free
of the disease.
That can be costly, because horses must be quarantined while they are
awaiting test results and must often be retested to ensure accurate results. In
addition, American horses that travel to other countries where piroplasmosis is
present must be tested before they can return.
The new tests--one for each of the two parasites that can cause the
disease--should speed up the process once they are accepted by international
regulatory authorities as appropriate tests. The current test, called a
complement fixation test, can give false positive or false negative readings.
The new tests rely on molecular techniques that give more accurate results.
Another advantage: The new tests do not require the use of live horses.
Genetic material used in the new tests can be grown in bacteria. The complement
fixation test relies on obtaining parasites and blood with antibodies from
infected live horses.
Donald Knowles, at ARS Animal Disease Research Unit in Pullman, Wash.,
and collaborators at Washington State
University developed the tests. ARS and WSU have applied for patents. VMRD,
a Pullman company that produces diagnostic test kits, plans to sell the tests
under a patent license within the next 5 years.
A story on these tests appears in the July issue of Agricultural Research, the
agencys monthly magazine.
ARS is the chief research agency of the U.S.
Department of Agriculture.
Scientific contact: Donald Knowles, ARS Animal Disease Research Unit,
Pullman, Wash., phone (509) 335-6022, fax (509) 335-8328,