Dr. Michael Smith: Everyone knows that ebola kills, but what exactly does it do? This worm-like virus has a devious way of working. Once it gets in the body, the virus attaches itself to the surface of the cells. Then it invades them, replicates, and causes the cells to explode, sending infectious particles flying. From there, Ebola overpowers the immune system. It uses the very cells that are meant to fight infection to travel to other parts of the body, including the liver, spleen, kidneys, and brain. It attacks almost every organ and tissue. The particle explosion also sets off an overwhelming inflammatory reaction. That’s what causes the sudden flu-like symptoms that are the first signs of ebola. Inside the blood vessels, the virus causes abnormal clotting and bleeding at the same time. Bleeding into the skin causes a red rash that appears all over. With the ability to clot normally destroyed, bleeding occurs internally as well as from the eyes, ears, and nose. This whole cascade of events causes the organs to fail. The loss of blood, along with organ failure, is what makes ebola so deadly. But if doctors can keep the organs working with intravenous fluids, blood transfusions, a ventilator, and other treatments, there’s a much better chance they can save lives. The infection moves fast and it can kill in 1 to 2 weeks. In the current outbreak, 60% of the people who caught the virus have died. Many more could likely be saved with better access to medical care. The risk of catching ebola is extremely low in the U.S., and officials are working round the clock to make sure it is contained. For WebMD, I’m Dr. Michael Smith.