In December of 2003 Kansas University professor Townsend Peterson published a map of Africa that predicted where future outbreaks of Ebola and Marburg might occur, based on the natural environment of areas that were know to have previously suffered from outbreaks of those diseases. The map was somewhat controversial, as it indicated areas that had not previously experienced filovirus outbreaks were at risk.
The predictive map he developed, published in the January 2004 issue of “Emerging Infectious Diseases,” was based on climatic and animal data from the areas where Marburg has been found. He said many scientists questioned whether the map accurately predicted that the possible Marburg zone could stretch west into Angola.
“We got a little flack for that,” he said.
As tragic as this outbreak is, the fact that the map accurately predicted where it might occur is good news, in that the pool of possible hosts for the Marburg virus is reduced down to an almost manageable size though that assumes that the various African filovirii are actually spread via animal contact rather than by animal behavior.
Most of the other outbreaks have been traced to caves or mines, Townsend said. If that remains the case, scientists can narrow the list of possible animal suspects to between 50 and 80.
Meanwhile, other African nations have belatedly begun to respond to the outbreak, instituting border checks and quarantines; an exceedingly proper response to events, given the apparent Angolan mismanagement of the crisis.
Meanwhile, Quiala Godi, the number two health official in the northern Angolan town of Uige — the epicentre of the virus — was critical of Luanda’s response.
“We have reached the peak of the Marburg epidemic. What worries me is the lack of support from the government. We haven’t received a single government team here in Uige,” Godi said.
“The hospital is closed,” he said speaking of the sole health facility there. “Even the emergency services are shut down. Here everything is politicised. Only international experts from the World Health Organisation and the Medecins sans Frontieres (Doctors without Borders) are here.”
Filomena Wilson, spokeswoman for a special commission set up by Angola’s health ministry to track the evolution of the virus, told AFP late Tuesday that there were “124 cases in Uige’s provincial hospital of whom 120 had died.”
Health officials in the field said 130 have died but the government says the fatalities number 117.
Godi said there were four more deaths on Tuesday — two in Uige and two at the nearby town of Negage about 30 kilometres (about 19 miles) away — which take the unofficial toll to 130, up from 126.
Wilson said international health workers were “working night and day” from house-to-house but confirmed that the hospital in Uige was closed, adding: “All the workers at the hospital in Uige have contracted the virus.”
She said the protective clothing being worn by health workers in Uige was akin to “astronaut suits”, adding: “They are completely covered to avoid contamination.”
Provincial health official Godi meanwhile heaped scorn on Wilson.
“These are people who simply talk. She didn’t even go to the hospital. She is scared of dying. The entire team sent by the health ministry has left leaving only international experts on the spot.”
Whether it ends up being due to SARS, Avian flu or some other germ entirely, the next worldwide pandemic will almost certainly be caused in part by similarly inept actions on the part of a Third World government.
It probably won’t be Marburg, as historically filovirus outbreaks kill their victims so quickly that they are unable to spread very far–though this latest outbreak is running contrary to the known storyline in a number of ways;
1. Age of the Victims – Far more children than adults have been infected. Typically one would expect an equal infection rate across all age groups.
2. Death Rate – No one is known to have survived infection with the virus in the current outbreak. That’s a 100% death rate, more deadly than Ebola, from a virus typically not expected to kill at that rate, though the death rate may be a reflection of the poor level of care available in Angola rather than the virulence of the virus.
Fatality rates for outbreaks of Marburg VHF have ranged from approximately 25 percent to 80 percent; mortality has been higher in outbreaks in which effective case management was lacking.
The outbreak may also be due to a new, deadlier variant of Marburg, which, like Ebola, has a number of different strains.
3. Incubation Period – Though this may be a symptom of journalistic confusion caused by the quarantine period those exposed to the virus are sentenced to rather than an actual observed trend, the incubation period for the Marburg virus is being reported as 21 days. Previously, 5 to 7 days was presumed to be the length of Marburg’s incubation period.
Based on the confused situation in Angola, all of the above should be taken with a grain of salt. It may be that the current outbreak adheres in every particular to the pattern laid down by previous outbreaks. It will likely be months before we know one way or another.
Background: Marburg in Angola, Hunting The Elusive Marburg, Mapping Ebola