Marburg Virus: The Hidden Killer

Author:  Mao Frances
Date:  October 2007

One of the most famous examples of inter-species viral transfer is the passing of HIV from primates to humans. Earlier this month, researchers have discovered that bats may potentially infect humans with the Marburg virus, a close relative to the Ebola virus. The infected bats, found in a lead and gold mine in western Uganda, display no symptoms and appear otherwise healthy. However, one mine worker died of Marburg hemorrhagic fever, while others that were infected apparently made a full recovery. Because of this, researchers are attempting to decipher whether or not the bats harbor the Marburg virus between periodic outbreaks in Africa.

The Marburg virus, which causes Marburg hemorrhagic fever, is potentially fatal. The symptoms are similar to that of other infectious diseases, such as persistent diarrhea, bleeding from body orifices (nose, gums, and vagina), and bloody vomit and feces. Transmission of the disease occurs through contact with bodily fluids, including blood, saliva, excrement, and vomit. However, if a patient survives, the recovery is complete, although it may be prolonged in some cases. Periodic outbreaks of the virus have occurred throughout southern Africa in the past three decades, but the virus's natural reservoir (i.e. where the virus hides in between outbreaks) has been previously unknown. "We're trying to see where this goes," says Jonathon Towner, the lead author of the report, who is a microbiologist with the Centers for Disease Control and Prevention.

In addition to the CDC, Towner is part of a group that is jointly sponsored by the World Health Organization and the National Institute of Communicable Diseases, a South African government group. Scientists from this group tested 1,100 bats representing ten different species found in Gabon and Congo, and found a total of four infected bats. The number, while admittedly not very large, may be indicative of a more widespread problem throughout sub-Saharan Africa.

However, the researchers remain cautiously optimistic. If it can be definitively shown that the bat is indeed the reservoir of the virus, then the next problem is to determine a feasible course of action. "The knee jerk reaction is to exterminate all the bats in the mine", said Towner, "but ecologically, that's a bad thing to do because the bats pollinate plants and eat harmful insects by the ton." As for a more practical solution, mine workers are advised to wear adequate protection (i.e. gloves, masks, hats, and respirators) in order to minimize the chance of Marburg infection through bat bites.

Author: Frances Mao

Reviewed by: Andrew Wang

Published by: Konrad Sawicki