Germany was among 10 other EU nations classed as "high concern" and France among three of "moderate concern".
Italy, Malta, Spain and Sweden were of low concern.
The agency said four countries had been raised into a higher category since the last assessment, and five countries had been lowered.
The number of cases and deaths is expected to increase by about 50 per cent over the next two weeks, the agency added, reaching a weekly rate of 300 new cases and 2.7 deaths per 100,000 population.
The assessment looks at the 27 EU nations as well as Norway, Iceland and Liechtenstein.