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Marburg virus
vaccine passes
test in monkeys
1998–2000
First documented large-scale
outbreak of Marburg virus —
154 cases, 128 fatal.
1967
Monkeys from uganda
cause outbreaks of
lethal virus in Marburg
and Frankfurt, Germany,
and in belgrade,
yugoslavia (now serbia)
— 32 cases, 7 fatal.
origin of virus’s name.
2008
two travelers separately contract Marburg
after visiting caves in
uganda—one dies.
uganda
By Nathan Seppa
A devastating tropical virus that has no
cure can be ambushed by vaccination
a day or two after exposure, tests in
monkeys show. The findings, appearing in the July Emerging Infectious
Diseases, suggest that African villagers,
health officials and laboratory workers
who come into contact with the often-deadly Marburg virus will someday
have a way to fend it off.
Marburg virus is related to Ebola virus.
Both cause hemorrhagic fevers—in
severe cases leading to shock, delirium
and organ failure — and both have high
mortality rates in people. In recent
decades, cases of Marburg virus have
shown up in Uganda, Zimbabwe, the
Democratic Republic of the Congo,
Kenya and Angola, sometimes spreading
to other countries via infected travelers
and animals.
Earlier research showed that monkeys
exposed to Marburg virus and vaccinated
within 30 minutes survived (SN: 5/6/06,
p. 277). In the new study, six rhesus
macaques were exposed to the virus and
not vaccinated until 24 hours had passed.
The strategy was designed to mimic situations in which people are exposed, says
study coauthor Heinz Feldmann, a virol-ogist at the National Institute of Allergy
and Infectious Diseases’ Rocky Mountain
Laboratories in Hamilton, Mont.
Five of the infected animals fended
off the disease; one died. Of six other
monkeys similarly exposed but not vaccinated until 48 hours had passed, two
survived and four died.
Clinical reports of past Marburg virus
outbreaks suggest that people can be
democratic
republic
of the Congo
2004–2005
largest outbreak of
Marburg virus to date—
374 cases, 329 fatal.
angola
Kenya
2007
three miners contract
Marburg virus — one dies.
Zimbabwe
The Marburg virus
has cropped up a
few times in central
and southern Africa
in recent decades.
sourCe: who, CdC
south africa
1975
australian traveler is
exposed to Marburg virus,
apparently in Zimbabwe.
he gets treated in Johannesburg, south africa. his
infection proves fatal. two
other people who catch
the virus from him survive.
exposed longer to the virus than monkeys
before showing symptoms. Feldmann
says that the window of opportunity for
vaccination after exposure might therefore be greater. Also the animals in these
tests were given a high dose of the virus,
possibly higher than the levels people
might be exposed to during an outbreak.
“This would have tremendous value
in public health workers and families
affected by Marburg virus outbreaks,”
says Daniel Bausch, an infectious disease physician at the Tulane University
School of Public Health and Tropical
Medicine in New Orleans. The key will
be to reach people in time, as most don’t
know when they have been exposed.
Delivered in a single injection, the
vaccine contains a livestock virus with
a single surface glycoprotein from the
Marburg virus. The resulting live, atten-
uated combination virus doesn’t cause
disease in primates, but it does awaken the
immune system, which gins up an army of
cells and proteins to fight infection.
