In one of my first immunology classes at university, we played a game called Pandemic.

We were each given two sterile Petri dishes filled with a standard agar growth medium, and a sterile and very sticky piece of toffee. We washed our hands thoroughly and then, in one hand, squeezed the toffee until our hands were gooey.

Each person then, one by one, shook hands with one other person. After the first round of hand-shaking, we swabbed our sticky hand and plated it onto the first agarose gel. Then we did a second round of hand-shaking, and plated again.

One toffee, out of the whole class, had been covered in a marker bacterium. The purpose of the experiment was to demonstrate how rapidly, through simple interpersonal contact, a disease could spread.

Michael Jackson had a skin disorder called Vitiligo. It is a chronic disorder that causes pigment loss in patches of the skin. In terms of its biology, it occurs when the melanin pigment-producing cells called melanocytes die are not able to function properly.

There is evidence to suggest that it is triggered as an event by a combination of immune, environmental and cellular development factors.

It is genetically inherited. The worldwide incidence of Vitiligo is between 1 to 2 per cent.

Charles Darwin’s theory of evolution by natural selection has been described as perhaps the most radical scientific theory ever proposed. For atheists such as Richard Dawkins it is the ‘universal acid’ which eats away the traditional view that the world was designed by God, with humans playing a key role in the cosmic drama. Those who want to preserve the traditional values naturally react very strongly, and the fulminations of modern Creationists continue the hostility expressed by many conservative thinkers in Darwin’s own time.