What is a pandemic? Could this really happen?

A pandemic is an epidemic or infectious disease that is spreading across a large region; for instance across a continent, or even globally. Many different organisms can cause such pandemics: smallpox, tuberculosis, HIV (AIDS), cholera, influenza - notably the 2009 flu pandemic (also refered to as H1N1 influenza virus, swine flu, mexican flu), typhus, measles, plague (black death), leprosy, malaria, yellow fever. Many pandemics with dramatic consequences have occurred in the past - and will in the future. In TWO JOURNEYS, a simple, modified common-cold virus seems to be the root cause of the demise of man.