Thank you for downloading more or less from BBC Radio 4.

Here's Tim Halford.

Hello and welcome to More or Less,

the programme which considers itself the sequined feather boa of statistics

and who are we to argue.

In this week's programme, we have cyclists running over guide dogs

and prisons full of sex offenders.

But first, if you've been listening to the news,

you could be forgiven for feeling very worried.

Doctors at the Royal Free Hospital in North West London

have begun treating a British nurse who caught Ebola in Sierra Leone.

The head of the World Health Organization

has warned that the outbreak of the deadly Ebola virus in Western Africa

is running out of control.

Ebola is probably the most contagious

and most deadly virus in the world.

The strain can kill up to 90% of its victims.

Most of those who get it will die through uncontrollable bleeding.

Ebola, a viral disease, has spread across West Africa,

affecting Guinea, Liberia, Sierra Leone and Nigeria.

Another separate outbreak has just been confirmed in Central Africa.

Now it's come to the UK.

...