Objective—To evaluate a portable real-time reverse
transcriptase-polymerase chain reaction (RT-PCR)
assay designed to detect all 7 viral serotypes of footand-
mouth disease virus (FMDV).
Design—Laboratory and animal studies.
Study Population—Viruses grown in tissue culture
and animals experimentally infected with FMDV.
Procedure—1 steer, pig, and sheep were infected
with serotype O FMDV. Twenty-four hours later, animals
were placed in separate rooms that contained 4
FMDV-free, healthy animals of the same species. Oral
and nasal swab specimens, oropharyngeal specimens
obtained with a probang, and blood samples were
obtained at frequent intervals, and animals were
observed for fever and clinical signs of foot-and-mouth
disease (FMD). Samples from animals and tissue cultures
were assayed for infectious virus and viral RNA.
Results—The assay detected viral RNA representing
all 7 FMDV serotypes grown in tissue culture but did
not amplify a panel of selected viruses that included
those that cause vesicular diseases similar to FMD;
thus, the assay had a specificity of 100%, depending
on the panel selected. The assay also met or exceeded
sensitivity of viral culture on samples from experimentally
infected animals. In many instances, the
assay detected viral RNA in the mouth and nose 24 to
96 hours before the onset of clinical disease.
Conclusions and Clinical Relevance—The assay
reagents are produced in a vitrified form, which permits
storage and transportation at ambient temperatures.
The test can be performed in 2 hours or less on
a portable instrument, thus providing a rapid, portable,
sensitive, and specific method for detection of FMDV.
(J Am Vet Med Assoc 2002;220:1636–1642)