Deadly Ebola virus on the move in Africa
A deadly Ebola outbreak in urban Guinea, where it had not been seen before, has reportedly killed more than 100 people there and in neighboring Liberia and Sierra Leone. The virus causes severe bleeding and has killed up to 90 percent of the people infected in some past outbreaks. Authorities suspect it was transmitted to humans in Guinea through contaminated bat meat and is now being passed from person to person. Read related article.
Why is Ebola so deadly?
Ebola creates holes in blood vessels, often causing bleeding and shock. It does this by killing endothelial cells, which form the blood vessels’ lining and other partitions in the body. When those cells die, blood and other fluids can leak out. Organs shut down.
The virus replicates very quickly, before most people’s bodies can mount an attack. People often have massive bleeding seven to 10 days after infection.
It effectively disables the immune system by hampering the development of antibodies and T cells that would target the virus. Scientists are not certain exactly how.
What can be done?
For now, only symptoms can be treated in hopes of keeping people strong enough that their immune systems can catch up. But within the past five years, several experimental vaccines and treatments have been effective in other primates, said virologist Alexander Bukreyev of the University of Texas Medical Branch in Galveston, and he estimates that something could be approved for human use within the next five years.
How does it spread?
The virus is often spread to humans in the contaminated meat of monkeys and other animals. It spreads from human to human through contact with body fluids.
SOURCES: Steve Monroe, deputy director of the CDC’s National Center for Emerging and Zoonotic Infectious Diseases; World Health Organization.