“It’s been a rough flu season this winter in the United States and Europe, but it could be worse. A lot worse,” science writer Carl Zimmer states in National Geographic’s “Phenomena: The Loom” blog. In other parts of the world, including Egypt, India and Cambodia, the H5N1 avian influenza strain is “lurking,” and according to official estimates, the disease has a case-fatality rate of 59 percent, he notes, adding that “may be a serious overestimate.” Zimmerman continues, “[E]ven if the true rate was only half as high, H5N1 would not be a virus you’d want to cross paths with,” and notes that the Spanish flu outbreak of 1918 had a case-fatality rate of about two percent and killed 50 to 100 million people worldwide.

Though scientists cannot predict how many people would die if an H5N1 outbreak occurred, “they can say this: what we do when and if we face an H5N1 pandemic could alter the evolution of the virus itself. And thousands of lives could be saved or lost as a result,” Zimmer writes. He explains the pathology of H5N1 and several laboratory experiments and mathematical models that try to predict how the virus might mutate to become more infectious. Zimmer describes how public health officials’ employment of isolation as a control technique during an outbreak could make the influenza strain less virulent but more widespread. The scenario “help[s] to sharpen our senses to the potential H5N1 has to evolve into something new. Whether the surprise is pleasant or horrifying may be, in part, up to us,” he concludes (2/7).