Elephants source of Marburg & Ebola?
From ANIMAL PEOPLE, June 2005:
LUANDA–The World Health Organization and Angola Ministry of
Health are optimistic that the worst outbreak on record of the
Ebola-like Marburg hemorrhagic fever may be close to burning itself
out, after 423 known cases through June 5, 357 of them fatal,
including 346 of the 412 cases that occurred in the city of Uige,
where the outbreak was first recognized.
The Uige outbreak may never be clearly traced to a source,
since the first persons exposed apparently all died before sharing
details about how they fell ill. Once either Marburg or Ebola
occurs among humans, it spreads chiefly through human contact.
Investigators are more optimistic about finding the origin of
an Ebola outbreak that struck the Cuvette-Ouest region of the
Republic of Congo in April, killing at least 10 people. The first
victims were “five hunters who became ill after emerging from the
forest,” Wildlife Conservation Society field veterinary program
director William Karesh posted to the International Society for
Infectious Diseases’ ProMed newsgroup.
“The 1st hunter died around April 25-26, and the last on
May 11,” Karesh wrote. The incubation period is about seven to 10
days, within a range of three days to two weeks. “The infected
hunters did not admit to eating or touching any ape carcasses. They
said they had eaten elephant, and survey teams have found numerous
elephant carcasses, illegally killed, in the area. The current
local belief is that the hunters died because they went to see a
witch doctor for a blessing before they went elephant hunting, and
failed to pay him. Hence, the Nganga put a curse on them.”
Karesh said two Wildlife Conserv-ation Society teams were
advancing along survey routes south of the Mambili River to seek the
source of the Ebola outbreak.
“They will collect samples from all species of carcasses
found, as well as ape feces for genetics and development of new
Ebola testing techniques,” Karesh said.
Responded ProMed moderator Jack Woodall, “Circumstantial
evidence supports the current belief that Ebola virus reaches the
human population as a result of the hunting, slaughter, and
consumption of non-human primates and perhaps other wild mammals,
which themselves may succumb to the infection. The primary reservoir
of Ebola virus has remained elusive,” Woodall acknolwedged, “and the
virus may be maintained in a species which does not exhibit signs and
symptoms of disease,” such as elephants.
Woodall first suggested that elephants might host Marburg,
Ebola, or both at the 1999 annual meeting of the American Society
of Tropical Medicine & Hygiene.
“I gave the following reasons for suspecting the elephant,”
said Woodall: “Pygmies have the highest filovirus antibody rate in
the Congo; they traditionally hunt elephants; and they poke around
in elephant feces to determine how warm the trail is.”