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Susceptibility
to Airborne Virus
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Although there is no evidence that sheep and goats are less susceptible to infection
than cattle and pigs, they generally exhibit fewer clinical signs.
Cattle are more susceptible to aerosol infection than other species.
Zebu cattle (Bos indicus) are less susceptible to disease than are Bos taurus.
Some strains of FMD virus appear to have a predilection for certain species. For example:
1. The 1996 Bulgarian type O outbreak strain was not reported to cause disease in
pigs, although pigs were known to have had contact with infected food.
2. The 1997 Taiwan type O outbreak strain grew poorly in non-pig tissue culture, and
experimentally was difficult to transmit to cattle.
It is probable that those host preferences shown by some strains of FMD virus are
genetically determined. However, the nature of these nucleotide sequences, and their
stability, is unknown.
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