New and dangerous infectious diseases are surfacing around the planet at an accelerating rate.
From the spread of Zika virus into the southern U.S. to an Ebola epidemic in West Africa, to a swine flu pandemic that began in Mexico, each of these recent health threats seems have taken the public by surprise.
But they shouldn’t have. We have been in a continuous battle for survival with bacteria, viruses and fungi that live in the environment and inside our bodies. History has been filled and shaped by infectious disease outbreaks that killed millions – from the plague in the Middle Ages to cholera deaths throughout Europe in the 19th century.