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Author(s): Nancy Moreno, PhD, Barbara Tharp, MS, Deanne Erdmann, MS, Sonia Rahmati Clayton, PhD, and James Denk, MA.

The Science of Microbes

Infectious diseases have plagued humans throughout history. Sometimes, they even have shaped history. Ancient plagues, the Black Death of the Middle Ages, and the “Spanish flu” pandemic of 1918 are but a few examples. 

Epidemics and pandemics always have had major social and economic impacts on affected populations, but in our current interconnected world, the outcomes can be truly global. Consider the SARS outbreak of early 2003. This epidemic demonstrated that new infectious diseases are just a plane trip away, as the disease was spread rapidly to Canada, the U.S. and Europe by air travelers. Even though the SARS outbreak was relatively short-lived and geographically contained, fear inspired by the epidemic led to travel restrictions and the closing of schools, stores, factories and airports. The economic loss to Asian countries was estimated at $18 billion. 

The HIV/AIDS viral epidemic, particularly in Africa, illustrates the economic and social effects of a prolonged and widespread infection. The disproportionate loss of the most economically productive individuals within the population has reduced workforces and economic growth in many countries, especially those with high infection rates. This affects the health care, education, and political stability of these nations. In the southern regions of Africa, where the infection rate is highest, life expectancy has plummeted in a single decade, from 62 years in 1990–95 to 48 years in 2000–05. By 2003, 12 million children under the age of 18 were orphaned by HIV/AIDS in this region. 

Despite significant advances in infectious disease research and treatment, control and eradication of diseases are slowed by the following challenges. 

  • The emergence of new infectious diseases 
  • An increase in the incidence or geographical distribution of old infectious diseases 
  • The re-emergence of old infectious diseases 
  • The potential for intentional introduction of infectious agents by bioterrorists 
  • The increasing resistance of pathogens to current antimicrobial drugs 
  • Breakdowns in public health systems

Funded by the following grant(s)

Science Education Partnership Award, NIH

Grant Number: 5R25RR018605