Researchers discovered that two natural compounds found in bat cave environments—isovaleric acid and ethyl methyl carbonate—can effectively kill the fungus that causes white-nose syndrome in bats. When used together, these compounds work even better than alone, disrupting the fungus’s cell membranes, causing it to produce too many reactive molecules (free radicals), and triggering cell death. This discovery offers hope for developing new treatments to protect bat populations that have been devastated by this disease in North America.