Zenerium Anthovirium

The Zenerium Anthovirium (ZA) is a virus that has made its way around the Earth since the dawn of time. It behaves much like the Influenza does. It slowly evolves new strains, with each strain posing more risk to human and animal health than the last strain.

Background
The ZA virus originates from XU-183, an asteroid that collided with YA-866, another asteroid. XU-183 separated into several fragments while YA-866 was scathed and its course redirected. The fragments of XU-193 bear the course to Earth.

In the year 3012 BC, the Ancient Egyptians witnessed the event. They observed the asteroids colliding with one another and breaking up. The Egyptians predicted the meteors from XU-183 would descend and land in specific areas around the world. The Egyptians were correct in their predictions. One meteor landed in Egypt, another landed in Eastern Russia, another on Pserimos, one to land in Africa, and the last one due to land in central Australia.

The meteorite sites seared and scarred the landscapes they landed on. They were no serious threat beforehand. However, overtime, as the soil and plant life recovered, the radioactive bacteria lingering around the crash sites from the meteorites began to assimilate with the soil and plants.

The bacterium from the meteorites embedded itself into the soil and plant life, remaining there to survive and grow. Over the years, the virus would evolve incredibly slowly. For the next several thousand years it would remain in secret, buried in the earth of the ever changing landscape. It would continue to grow through the plant life slowly emitting its biological threats amongst the plants.

Normally, plants would detect a foreign parasite residing in itself and kill itself off to prevent its spread. Unfortunately, the plants could not detect the foreign body. The plants themselves never exhibited any visual states of decay or infection.

Evolution
The ZA virus would develop its first strain in which it would affect humans when the Bubonic Plague (Black Death or Black Plague) would interfere with its growth on Pserimos. The Bubonic Plague traveled to Pserimos aboard rats on ships after the British Captain Alban Wright colonized Pserimos in 1603 AD.

Animals infected with the Bubonic Plague regularly ate the plant life on Pserimos which in turn transmitted the virus amongst each host. When the Bubonic Plague parasite was transferred into the ZA infected plants, the bacteria in the plants would detect the foreign parasite intrusion and change in order to survive.

The horizontal gene transfer method amongst the bacteria in the plants allowed it to survive against the foreign invading parasite. Thus, allowing it to conform and mutate its microorganisms to a new state. Due to this change, the Zenerium Anthovirium Zero (ZA-0) was born.