As of Feb. 25, 2020, the World Health Organization reported 79,339 confirmed cases of novel coronavirus, also known as COVID-19. Thirty-four countries have reported cases, including 2,619 deaths.
The WHO has not declared COVID-19 as a pandemic — a situation defined somewhat vaguely by the WHO as “the worldwide spread of a new disease.”
Michael Vahey, assistant professor of biomedical engineering at the McKelvey School of Engineering at Washington University in St. Louis, researches viruses and the mechanisms and circumstances that make them more or less capable of reaching pandemic status.
In the past, the world has seen pandemics infect and kill millions: The 1918 influenza is estimated to have killed 50 million and the bubonic plague killed an estimated 25 million people in Europe — one third of the continent’s population.
In this video, Vahey explains the properties of a virus that allow it to spread so rapidly across the world, reaching pandemic status:
- Viruses that become pandemics are usually zoonotic in nature; they have made the leap from non-human animals into humans.
- Once in humans, viruses need to be able to survive and thrive in their new environment if they are to reach pandemic status.
- Pandemic viruses also need to be able to spread efficiently from human to human in order to infect people around the globe.
Vahey also offers some advice for predicting and preparing for emerging pandemics.
He is scheduled to speak Feb. 26 in Thailand at a National Institutes of Health Conference on Emerging Infectious Diseases in the Pacific Rim.