WHEN PROTO LAUNCHED ITS INAUGURAL ISSUE IN 2005, researchers were anxiously watching a new flu virus called H5N1, which many were concerned might lead to a global pandemic.

Although no global crisis came from H5N1, the fear of a new pandemic—whether from new influenza strains or the Ebola virus—is very much alive. Such fears led some researchers to engineer the H5N1 virus with mutations that made it more dangerous, so that researchers might study it and stay one step ahead.

In this video, Martin Hirsch, a senior physician in the infectious disease service at Massachusetts General Hospital, discusses the controversy that followed work on H5N1. He also talks about the advances in public health that aim to keep scientists one step ahead of these diseases.

Hirsch is encouraged by “how good the public health system is in protecting against these viruses.” “Each year, each month, each day,” he says, “we learn a little bit more. But it is a constant fight with new viruses emerging all the time.”