Influenza type A
NOTE: THIS TEST IS NOT PERFORMED
ON SAMPLES TAKEN FROM BIRDS OWNED OR LOCATED IN THE STATE OF
- Ultrasensitive qualitative detection of influenza A virus by reverse transcription coupled real time polymerase chain reaction. This assay detects
but does not differentiate most known strains of influenza A viruses,
including H1N1, H2N2, H3N2, H3N8, H4N6,
H5N1, H5N2, H7N2, H7N7, H8N4 and H9N2.
included in P0013 - equine
one of the most important respiratory diseases of the horse. It
is a severe acute upper respiratory infection, and typical
symptoms include pyrexia, dyspnea, anorexia and coughing. In
countries where breeding and racing horses is a major industry,
outbreaks of the disease can result in significant economic
causing equine influenza belongs to the orthomyxovirus family.
There are two subtypes of equine influenza virus, A/Equi 1/H7N7,
first isolated in 1956, and A/Equi 2/H3N8, first isolated in
1963. Both subtypes have caused disease. However, it is
generally accepted that A/Equi 1/H7N7 has not been isolated
since 1979 and may be extinct (van Maanen and Cullinane, 2002;
Webster, 1993). In contrast, outbreaks of A/Equi 2/H3N8 continue
to occur worldwide with the exception of a few isolated areas
where equine influenza has never been recorded, including
Australia, New Zealand and Iceland.
with subtype A/Equi 2/H3N8 is enzootic in North America and
Europe. Evidence suggests that two separate lineages of this
subtype have evolved, and outbreaks occur frequently despite
mandatory vaccination of some horse populations (Daly et al.,
1996; Mumford and Wood, 1993; Office International des
Epizooties, 2000). Influenza is a highly contagious disease and
the introduction of even a single infected horse can lead to its
rapid spread in unprotected horses over a wide geographic area.
In South Africa in 1986, the introduction of the virus into the
country for the first time resulted in thousands of horses
suffering severe respiratory disease and horse racing was
suspended for 5 months.
in international movement of horses by air transport for racing
and breeding purposes has led to the requirement for a rapid
method to isolate horses that are carriers of this virus.
Traditionally, equine influenza virus is diagnosed by the
isolation of virus from nasopharyngeal swabs in embryonated hen
eggs, or by the detection of a fourfold-or-greater rise in
antibody titer in paired sera by hemagglutination inhibition
(Office International des Epizooties, 2000). A recent study (Quinlivan
et al., 2004) has shown that both virus isolation and molecular
detection by reverse transcription PCR are much more sensitive
than serological methods such as the Directigen Flu A test. In
contrast to virus isolation, reverse transcription PCR detection
is rapid and highly specific.
Help confirm the disease causing agent
Shorten the time required to confirm a clinical
diagnosis of influenza
Help ensure that horse populations are free of influenza
Early prevention of spread of this virus
Minimize personnel exposure to this virus
Safety monitoring of biological products that derive
Daly, J. M., Lai, A.C.K., Binns, M.M., Chambers, T.M.,
Barrandeguy, M. and Mumford, J.A. (1996) Antigenic and genetic
evolution of equine H3N8 influenza A viruses. J. Gen. Virol.
Mumford, J. A., and Wood, J.M. (1993) WHO/OIE
meeting: consultation on newly emerging strains of equine
influenza. Vaccine 11:1172-1175.
Office International des
Epizooties (OIE) (2000) Equine influenza, p. 546-557. In Manual
of standards for diagnostic tests and vaccines. OIE, Paris,
Quinlivan, M., Cullinane, A., Nelly, M., Van Maanen,
K., Heldens, J. and Arkins, S. (2004) Comparison of
sensitivities of virus isolation, antigen detection, and nucleic
acid amplification for detection of equine influenza virus. J.
Clin. Microbiol. 42:759-763.
van Maanen, C. and Cullinane, A.
(2002) Equine influenza virus infections: an update. Vet. Q.
Webster, R. G. (1993) Are equine 1 influenza
viruses still present in horses? Equine Vet. J. 25:537-538.
-- nasopharyngeal swab.
-- 0.2 ml whole blood in EDTA (purple top) tube.
Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.
specimen types, if there will be a delay in shipping, or during
very warm weather, refrigerate specimens until shipped and ship
with a cold pack unless more stringent shipping requirements are
specified. Frozen specimens should be shipped so as to remain
frozen in transit. See shipping
instructions for more information.
2 business days
reverse transcription coupled real time PCR