Off the Cuff: The 1918 Flu in 2018

Marc Lipsitch
Marc Lipsitch, professor of epidemiology; director, Center for Communicable Disease Dynamics

Q: If the 1918 flu virus—which killed between 50 million and 100 million people worldwide—were to appear in 2018 with all its lethality, would we be better or worse off than we were a century ago?

A: There are a lot of reasons why things would be better now, and a number of reasons why they would be worse. They would be better because we have seen, in the 20th century and the beginning of the 21st, a steady decline in the rate of mortality from all kinds of infectious diseases put together. When you look at a graph, the 1918 flu is an enormous spike that’s visible to the eye, unlike any other spike in the 20th century. But the overall trend is way downwards. It’s due to a number of very basic public health measures: better nutrition, clean water and sanitation, possibly better ventilation, and less crowding. On top of that, in the developed world, we have anti-infective drugs, vaccines, supportive care.

The bad side would be the interconnectedness of the world, our daily dependence on functioning transportation and supply chains, and the just-in-time nature of almost everything, from food to hospital supplies. A disruption in one place has knock-on effects everywhere. We can’t just live off the land while we wait for the flu to pass. The connectedness of the world also means that there are fewer opportunities for rescue. If there’s a hurricane today, for example, people bring trucks from all over the region to the site of the disaster. But if there’s an infectious disease everywhere, you can’t bring to bear the resources of a whole region or country—because it’s not a localized problem. Everyone will suffer at the same time.

On balance, we’re in a better position. But if a flu pandemic got to the point of stopping important social and economic activities, we would be more vulnerable than in 1918, because financial markets and the general scale of disruption would have huge ripple effects that weren’t conceivable 100 years ago.

Madeline Drexler

Photo: Kent Dayton/Harvard Chan