The Plague

In the Year 2020, a rocket containing several strains of a biological weapon impacted in San Fransisco, California on January 17. Its payloads were fatal to nearly all humans and within several weeks, it had wiped out 70% of human life in the US. Eventually, the events after the initial rocket's landing would bring the entirety of human civilization to a grinding hault and only decades later would any semblance of human life be seen.

The Landing
The rocket embedded itselft partially in the ground and it took several days to remove. Initially, it was though to have been a nuclar warhead that did not detonate properly, as there was a nuclear device in the nose. However, it turned out that this was a decoy for the biological payloads contained deeper in the rocket.

People grouped around the rocket but were soon shoed away by military personal that moved in soon after.

Path of the Plague
On January 19, the rocket was to be removed and brought to a local military facility for research. The three miles surrounding the crash site were evacuated for safety purposes. At this point it was confirmed that the weapon did not contain a nuclear payload so the rest of the city was operating normally, albiet anxiously.

On January 20, several researchers became horribly ill and died soon after. The plague spreads from there throughout the western states. By January 23, California had been declared a "dead zone" and the borders were locked down.

By January 30, most of North America was comprimised by the plague and by the start of Febuary, rockets containing the plague had landed in Austrailia, England, Germany, Russia, North and South Korea, and China.

Febuary 5, rockets hit Mexico, North Africa, and India.

Febuary 20, all communication from America has ceased, and only small pockets of Southern Italy remain clean in the western world.

March 5, the only operating first world country, Japan, begins sinking any ships that come within range of artilery. Martial law is declared.

March 20, several plague rockets hit Japan. Within 6 hours, mass panic causes untold amounts of damage to infastructure.

March 28, last human-triggered wireless signal for the next 20 years.

Strains
While many traits of the plague were common between strains, there were some differences. The variety of strains was one of the main ways the plague was so effective.

SBS-40 a.k.a. "Hell Cough" was the first of three strains to affect the United States. It spread through mucus, insect bites, and water sources. As its name states it caused its victims to have bouts of severly painful coughing and headaches. It would kill after 3 days.

SBS-41 a.k.a. "Jitter Fever" was the second strain to affect the Unite States and the main strain that affected Europe. It was responsible for most deaths of people younger than 10 and older than 50. It caused its victims to act confused, panicked, and irrational. The disease would then trigger a high fever that would kill the infected. Normally killed in 20 hours.

SBS-83 a.k.a. "Zombie" was the strain that killed most of Asia. It spread through air, water, and casual contact. It caused its victims to become confused and wander around in an unresponsive "hypnotised" state. The disease would kill 15-20 hours, by cutting off oxygen to the brain.

SBS-29 was the final strain. It exclusively landed in Japan. It often killed in 9 hours or less and was spread by casual contact, air, and water. It caused fevers and hallucinations.