You probably haven’t thought about the bird flu in a couple of years, unless you’re a virologist, but a new strain that resurfaced in China has the potential to be pandemic. The H7N9 virus only caused mild illness in poultry until recently, but a genetic change means the new strain is deadly for birds. Now, H7N9 has led to more human deaths this season than any other season since it was detected in people four years ago

Between September and March 1, 162 people perished from H7N9. Human cases have increased since December, with reports from eight different provinces in China. Hong Kong University research lab director Guan Yi told NPR, “We’re trying our best, but we still can’t control this virus. It’s too late for us to eradicate it.”

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