Airlines, marine vessels, road, and railway transport networks continue to connect to the far corners of the globe. With these increased connections, travel time has decreased while travel speed and the volume of passengers and goods transported have increased. An advantage of ever-increasing mobility is that it aids disaster relief, recovery, and reconstruction efforts in the aftermath of a disaster. Thus, reducing the vulnerability of regions exposed to non-epidemic catastrophes. However, the consequences of both long- and short-range movements have also made the global human and animal population vulnerable to epidemic disasters because pathogens and their vectors can now move further, faster, and in greater numbers than ever before. Hence, putting more pressure on healthcare, technology, and government to develop and administer vaccines and antivirals to lower our vulnerability.
A disaster results from the complex interaction between and combination of factors and development processes that generate conditions that create vulnerability to a hazard depending on the exposure. Vulnerability depends on the combination of economic, social, governmental, healthcare, technological resources and measures of mitigating the impact of the extreme external shock, i.e. a pandemic. If the vulnerability exists (no or limited economic, healthcare, technological, etc. resources), being exposed (spatially and temporally) to a given hazard, and the fact of not being able to address the consequences of the extreme external shock is a disaster. Rapid and uncontrolled urbanization as well as global population growth, for example, can contribute to the (re-)appearance and facilitate the spread infectious diseases, since humans and animals are living in closer proximity to each other.