(CSIS) Two children contracted polio in western Ukraine, right at Europe’s doorstep, in August 2015. This outbreak and response laid bare the degree to which Ukraine’s immunization and overall health system are broken, well beyond what had been commonly understood, crippled by deep corruption, inadequate financing, and widespread popular mistrust. In global terms, Ukraine, the black box of eastern Ukraine, and some neighboring countries amount to a regional danger zone of weak health security capacities to prevent, detect, and respond to threats. Though it was possible for external interests to rally to launch new campaigns (after frightening delays), the acute shortcomings plaguing Ukraine and others in the region persist. The proper reaction from the global health community is a sober, realistic admission: we will almost certainly see a proliferation of infectious outbreaks in Ukraine and the Balkans, especially as governments struggle with a continued massive influx of refugees. An intensified reaction from the United States, European Union, and broader international community is imperative.