Ebolavirus Reston was detected in samples taken from
pigs on two farms in the northern Philippines in mid-
2008. This was the first known case of any of the
filoviruses being detected in pigs anywhere in the world.
Previously, filoviruses have only been isolated from
humans and non-human primates, although serological
evidence indicates that bats may also be infected with
these viruses. Serological evidence of infection was also
detected in six of 147 in-contact people tested as part of
the investigation into this outbreak.
some concern has been expressed that pigs could serve as an
amplifying host in much the same way that they did for the
initial outbreak of Nipah virus, with subsequent transmission of
infection to humans. The origin of the infection in these pigs
is unknown, but is likely due to ongoing exposure to an as yet
unknown reservoir host. Previous research implicates bats as the
most likely suspect 1.
Sequencing of the Ebola-Reston virus genome, recovered from
these pigs, found some genetic variability, with three variants
being identified from the one herd of pigs. For a virus which is
relatively stable genetically (unlike influenza viruses) this level of
divergence may indicate that this virus is not a recent import into
the northern Philippines. It is likely to be prevalent in a reservoir
host, which has close contact with pigs in this area, allowing
multiple introductions to these herds