Pandora - Evolution Gone Wrong

On 21/12/2012 a deadly ancient virus, we now know as 'Pandora' escapes from deep beneath the earth crust. After a minor earthquake hits. Lying dormant for centuries this ancient killer once responsible for the extinction of the dinosaurs, spreads fast through the oceans of the world contaminating and killing, every living ocean faring creature. Seeing it as a subsequent feast, starving humans welcome the thousands of fish washing-up on shore. Pandora now becomes airborne moving south, riding the winds to all four corners of the earth, and sweeping across the planet like a curse, devouring everything in its path. Destroying all life, bringing about our destruction. Like a silent stalker, it attacks the elderly and sickly first; striking them down like a bolt of lightning. Then moves on to the rest of the population, killing 99% in under a month. Leaving only children under 16 and pregnant mothers behind. Those who survive retreat to the sewers. Those that do die don't stay dead for long they comeback.