But the polio epidemic in Tajikistan and Russia is considered one of the most serious emerging threats, with devastating potential for Europe, and Dr. Coulombier said the agency is urging member states not to lower their guard.
“This is a major one,” Dr. Coulombier said. “We have under-vaccinated populations in the EU. We know that the EU could be at risk of seeing the re-emergence of polio in these populations.”