Emerging Viral Diseases Are Global Threat

Emerging Viral Diseases Are Global Threat



Aug. 2007  - Marburg hemorrhagic fever is 
a global threat to public health, the World Health Organization says in a 
new report on the disease. 
"Emerging viral diseases such as ebola, marburg hemorrhagic fever and 
nipah virus pose threats to global public health security and also require 
containment at their source due to their acute nature and resulting 
illness and mortality," says a summarized version of the 2007 World Health 
report due to be released in Geneva tomorrow. 
Marburg hemorrhagic fever is a severe and highly fatal disease caused by a 
virus from the same family as the one that causes Ebola hemorrhagic fever. 
Both diseases are rare, but can cause dramatic outbreaks with high 
fatality. These viruses are among the most virulent pathogens known to 
infect humans. There is currently no specific treatment or vaccine, 
according to the World Health Organization.
Two cases of Marburg virus infection have recently been reported in 
Uganda. One of the people, a miner, died in July. 
Results of laboratory tests on blood samples from Kampala and Kamwenge 
performed by the U.S. Centers for Disease Control and Prevention, CDC, 
have confirmed Marburg virus infection in the mine worker, and in one of 
his close contacts during his illness. 
Contact tracing and monitoring has been carried out to ensure no further 
transmission of disease, and the extended contacts are coming to the end 
of their period of observation. 
An international team of scientists is working to identify the hosts of 
the virus and mode of its natural transmission in the environment. They 
are focusing on bats living in mines near where the miner became ill.
 
On Friday, experts from the CDC, the National Institute of Communicable 
Diseases in South Africa and the World Health Organization entered a lead 
and gold mine in a remote forest reserve in western Uganda to search for 
bats, which are suspected to be the source of the latest Marburg outbreak. 


Located inside the Kitomi Forest Reserve, the mine is surrounded by hills 
and banana plantations. The nearest community is five kilometers (three 
miles) away and there is a miners' camp nearby. 
The mine had operated, sometimes illegally, from the 1930s to the 1980s 
when it was abandoned. Since it legally reopened last January, between 50 
and 90 miners dig there for lead and gold ore. 
Wearing protective gear, members of the ecological team set up mist and 
harp nets every night to catch bats as they leave the mine to hunt for 
food and water. They catch about 100 bats every night and aim to net more 
than 1,000.

The captured bats are taken to a nearby laboratory, established for 
Marburg research, where scientists there work through the night, taking 
blood and organ samples to look for Marburg virus antibodies. 
The blood and organ samples are preserved in liquid nitrogen and carried 
to Kampala. They will then be transported to laboratories of CDC in 
Atlanta, Georgia, and of NICD in South Africa for further analysis. 
Illness caused by Marburg virus begins abruptly, with severe headache and 
severe malaise. Many patients develop severe hemorrhagic manifestations 
between days five and seven, and fatal cases usually have some form of 
bleeding, often from multiple sites. 
Fatality rates have varied, from 25 percent in the initial 
laboratory-associated outbreak in 1967, to more than 80 percent in the 
Democratic Republic of Congo from 1998-2000, to even higher in the 
outbreak that began in Angola in late 2004. 
There is no precise evidence indicating how Marburg virus is transmitted 
to humans, but the World Health Organization says bats are suspected to 
play a role. 

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