S0069 - Ultrasensitive qualitative detection of
encephalomyocarditis virus by reverse transcription coupled real time
polymerase chain reaction
Encephalomyocarditis virus (EMCV) is a single stranded
picornavirus belonging to the cardiovirus genus that infects
many animal species including pigs, rodents, cattle, elephants,
raccoons , marsupials, baboons, macaques, chimpanzees and humans
. Rats and mice are the natural hosts of the virus, but pigs are
the most commonly and severely infected domestic animals. The
ability of this virus to cause interspecies infections had led
to numerous outbreaks in zoos in Australia and the United States
(Reddacliff et al., 1997; Wells and Gutter, 1989). These
outbreaks involved multiple animal species including lemurs,
squirrels, macaques, mandrills, chimpanzees, hippopotami,
kangaroos and possibly humans. Humans infected with this virus
had been shown to have fever, neck stiffness, lethargy,
delirium, headaches, or vomiting (Gajdusek, 1955; Murname,
1981). In recent years, there has been renewed interest in this
virus, especially in pig-to-human transmission, because of
advances in xenotransplantation as a means of overcoming the
acute shortage of transplantation tissues and organs for humans.
In the past,
diagnosis of EMCV was based on virus isolation and
identification. This method is time-consuming and the virus is
difficult to isolate from infected animals. Experimental EMCV
infection in pigs showed that virus could no longer be isolated
after 3 days post-infection (Foni et al., 1992), but the virus
may continually persist for a long period in infected pigs
without any clinical signs (Billinis et al., 1999). Confirmation
of this pathogen has relied upon the development of circulating
antibody, but this diagnostic approach is not reliable because a
recent study in pigs has shown that some infected pigs may not
develop antibodies against EMCV (Brewer et al., 2001).
detection by PCR is the most rapid, sensitive and specific
method for the diagnosis of this infection. PCR methodology can
reduce the frequency of false negative diagnoses of this virus.
Help confirm the disease causing agent
Help ensure that animal groups or populations are free of
Early prevention of spread of this virus among a
Minimize human exposure to this virus
Reddacliff, L. A., P. D. Kirland, W. J. Hartley, and R. L.
Reece. (1997) Encephalomyocarditis virus infections in an
Australian zoo. J. Zoo Wildl. Med. 28:153-157.
Wells, S. K.,
and A. E. Gutter. (1989). Encephalomyocarditis virus: epizootic
in a zoological collection. J. Zoo Wildl. Med. 20:291-296.
Gajdusek, C. (1955). Encephalomyocarditis infection in
childhood. Pediatrics 16:819.
Murname, T. G. 1981.
Encephalomyocarditis, p. 137-147. In G. W. Beran (ed.), CRC
handbook series in zoonoses, section B, vol. 2. Viral zoonoses.
CRC Press, Boca Raton, Fla.
Foni, E., Barigazzi, G., Sidoli,
L., Marcato, P.S., Sarli, G., Della Salda, L. and Spinaci , M.
(1993). Experimental Encephalomyocarditis virus infection in
pigs. J. Vet. Med. 40:347–352.
Paschaleri-Papadopoulou, E., Psychas, V., Vlemmas, J., Leontides,
S., Koumbati, M., Kyriakis, S.C. and Papadopoulos , O. (1999)
Persistence of Encephalomyocarditis virus (EMCV) infection in
piglets. Vet. Microbiol. 70:171–177.
Brewer, L.A., Lwamba,
H.C., Murtaugh, M.P., Palmenberg, A.C., Brown, C. and Njenga,
M.K.(2001) Porcine encephalomyocarditis virus persists in pig
myocardium and infects human myocardial cells. J.Virol.
Specimen requirement: 0.2 ml whole blood in EDTA (purple top) or ACD (yellow top)
tube, or 0.2 ml plasma or serum, or 0.2 ml fresh or frozen
types other than those listed here, please call 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