How many people have been infected? More than 1,600 people in Guinea, Liberia and Sierra Leone have contracted Ebola since March, making this the biggest outbreak on record. More than half of those infected have died.
How contagious is the virus? You are not likely to catch Ebola just by being in proximity with someone who has the virus; it is not airborne, like the flu or respiratory viruses such as SARS. Instead, Ebola spreads through direct contact with bodily fluids. If an infected person’s blood or vomit gets in another person’s eyes, nose or mouth, the infection may be transmitted. In the current outbreak, most new cases are occurring among people who have been taking care of sick relatives or who have prepared an infected body for burial. Health care workers are at high risk, especially if they have not been properly equipped with protective gear. The virus can survive on surfaces, so any object contaminated with bodily fluids, like a latex glove or a hypodermic needle, may spread the disease.
How does the disease progress? Symptoms usually appear about eight to 10 days after exposure. At first, it seems much like the flu: a headache, fever and aches and pains. Sometimes there is also a rash. Diarrhoea and vomiting follow. Then, in about half of the cases, Ebola takes a severe turn, causing victims to haemorrhage. They may vomit blood or pass it in urine, or bleed under the skin or from their eyes or mouths. But bleeding is not usually what kills the patient. Rather, blood vessels deep in the body begin leaking fluid, causing blood pressure to plummet so low that the heart, kidneys, liver and other organs begin to fail.
How is the disease treated? There is no vaccine or cure for Ebola, and in past outbreaks the virus has been fatal in 60 to 90 per cent of cases. All physicians can do is try to nurse people through the illness, using fluids and medicines to maintain blood pressure, and treat other infections. A small percentage of people appear to have an immunity to the Ebola virus.