The workers had been contaminated as they took organ samples from green monkeys imported from Uganda. Up to the end of the 20th Century, rare cases of violent haemorrhagic fever attack linked to Marburg virus were subsequently registered, essentially in East Africa: (in Kenya, Zimbabwe, parts of South Africa).
However, in 1998, a more extensive epidemic affected 149 people near Durba, a town in the North-East of the Democratic Republic of Congo (DRC). More than 80% of these people succumbed to the haemorrhagic fever the virus caused. In 2005, a second epidemic that broke out in Angola infected over 252 people, 227 of whom died - a mortality rate of nearly 90%. That was the most severe epidemic of Marburg haemorrhagic fever (MHF) known to date.
Between 2005 and 2006, scientists from IRD working in conjunction with CIRMF and CDC conducted a research campaign with the aim of detecting Ebola virus among species of fruit bat (mammals of the order Chiroptera). In the context of this study, five trapping sites were set up in the tropical rainforest of Gabon and the North-West of the Democratic Republic of Congo. The 1138 specimens of fruit bat collected belong to 10 different species. At the same time, Angola, about 800 km from the study area, experienced a severe outbreak of MHF. However, the natural reservoir of this virus was still unknown. In addition to the search for Ebola in each of the chiropteran specimens caught, the researchers looked for the presence of its cousin in their tissues. A series of analyses were performed on the bats captured: detection of viral RNA in the liver and spleen by various methods of nucleotide amplification; a search for Marburg virus-specific antibodies in the blood; phylogenetic characterization of amplified genomic fragments.
Previous research on Ebola virus showed that human infection comes about through the intermediary of infected great ape carcasses. The viral transmission to primates occurs in the dry season, a period when food resources become increasingly scarce.
The great apes then come into competition with bat species for fruit supplies when foraging and can be infected notably by blood or by placental fluid that escapes when bats give birth. The mode of contamination by Marburg virus appears to be different, however. It does not appear to need any intermediary to be pathogenic for humans, as foreseen from data of the latest two epidemic outbreaks. In one outbreak, which raged in the north-east of DRC in 2000, most people infected worked in a goldmine, which turned out to be the refuge for a large colony of Egyptian rousettes. During the second epidemic, in Angola, the first victims were children who had gathered fruit from trees where a large population of this species of fruit bat roosted. Other evidence was the fact that the capture sites chosen for this study were all located near caves harbouring sizeable groups of these bats. Moreover, the discovery of such bats that were carriers of Marburg virus in Gabon, a country where no clinical case has yet been recorded, gives an incentive for setting up surveillance and prevention measures in regions where no MHF virus epidemic has ever occurred.
The findings should be useful in the future for defining more accurately the geographical areas potentially affected by Marburg virus. They could also help in extended studies, particularly in West Africa, a significant region for migration of Rousettus aegyptiacus. This identification of the virus’s natural reservoir should also favour the development of public health measures and prevention strategies involving local people which could minimize the infection potential of possible MHF epidemics to come.
Grégory Fléchet - DIC
Grégory Fléchet | alfa
First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife
Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
25.10.2016 | Earth Sciences
25.10.2016 | Power and Electrical Engineering
25.10.2016 | Process Engineering