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cheat sheet

by hazel FlyNNstart at the begiNNiNg: not everyone who catches ebola virus disease will die, but it kills at a far higher rate than many other diseases. africa is currently experiencing a headline-making outbreak of the disease, which is spread by person-to-person transmission. In previous epidemics, 50% of affected people died but without medical treatment this can rise as high as 90%. the Who has reported a fatality rate during the current epidemic in West africa of about 72%. this drops to 60% for patients in hospital.

EbolaWhat are its OrigiNs? the first outbreak of 602 recorded cases was in 1976 in sudan

and in the Democratic republic of congo (formerly Zaire), near

the ebola river. It may have been initially spread as a result of handling bushmeat

(wild animals hunted for food) or contact with

infected bats. the current ebola outbreak, mainly in the West

african countries of guinea, liberia

and sierra leone, began in march 2014 and is the worst so far. By December, there were more than 17,000

people infected and more than 6000 deaths recorded.

tell Me MOre: symptoms appear anywhere from 2-21 days after exposure, but most commonly show up in 8-10 days. unlike, say, chickenpox, a person with ebola cannot spread the disease before their symptoms appear. the virus passes from one person to another only by direct contact with blood and bodily fluids, which may enter the body through mucous membranes or breaks in the skin. It is not spread through the air. People caring for the sick or handling the bodies of people infected with ebola are particularly exposed.

at first, ebola seems much like the flu, causing headaches, pains and fever. Vomiting and diarrhoea and sometimes a rash follows. more than two-thirds of sufferers will then experience a severe decline as the virus causes them to haemorrhage; they may pass blood in urine or vomit, or from the eyes or mouth. Death is usually caused by organ failure and septic shock following the drastic loss of blood pressure when blood vessels leak fluid.

is there aNy gOOd NeWs? yes. ebola is not nearly as contagious as you might fear. each person with ebola passes it to 1.5 to 2 others. In comparison, measles is far more easily transmittable (an average of 18 contagions), but does not have the same high mortality rate. also, hospital healthcare measures such as fluid management and blood transfusions can greatly increase survival rates. Finally, several potential vaccines are now in active development.

Us$1.3m:cost of two ebola patients at nebraska medical center, us. a 70-bed purpose-built ebola unit in Bong, liberia, costs

$1m/month to run and an average liberian centre spends $1200/patient.

Sources: Washington Post; Forbes.com; Samaritan’s Purse

Instant answers

“As we work to help the communities affected by this virus, we must not let our fear outweigh our compassion” Dr Tom Frieden, Director of US Centers

for Disease Control and Prevention (CDC)

GUINEASIERRALEONE

LIBERIA

SUDAN

DEMOCRATICREPUBLIC OF CONGO

6070:Deaths in the first nine months

of the current outbreakSource: WHO, December 3, 2014

Ebola is a filovirus, with a threadlike structure. Its spiky

surface helps viral particles attach to cells and proceed to

enter them and replicate