Skip to main content

How and Why Do Animal Viruses Jump

Published February 28, 2022


Spillover events, just like the Black Death in the 14th century, continue today. Watch this engaging short video to learn more about this phenomenon, which has more recently brought us AIDS, and COVID-19. Spillover events are happening much more frequently in the 2000s, and the concept of One Health can help us understand why. Moreover, did you know about spillback? Kelly Cowan explains this in her trademark accessible style in this video.

Approximately how much longer have bacteria been on Earth than humans?

  1. 1.1 trillion years
  2. 4.3 billion years
  3. 1.1 million years
  4. 10 billion years
  1. Do all zoonotic diseases have the capacity to cause human pandemics?
    1. no
    2. yes
    3. sometimes
  2. The COVID-19 pandemic was caused by
    1. human practices
    2. climate change
    3. viral mixing in bats
    4. all the above



About the Author

Kelly Cowan has taught at Miami University since 1993 and was the Middletown Campus Dean from 2005-2009. She was interim director at the local campus of Cincinnati State and Technical College for 2015. She is the author of two successful McGraw-Hill microbiology textbooks. Her interest in under-resourced students led her to her now full-time engagement in two arenas: 1) with students and residents in generational poverty; and 2) with institutions - civic and educational - who serve them. Kelly grew up in eastern Kentucky and was educated at the University of Louisville, the University of Maryland, and the University of Groningen, in the Netherlands. She founded a large non-profit in Middletown that supports the cradle-to-career education of under-resourced families helping them move to self-sufficiency. Kelly is also available, schedule permitting, to speak on these topics at your school, at no or little cost to you. To contact Kelly, please visit her website at

Profile Photo of Kelly Cowan