BRUSSELS — European Union officials urged member nations Thursday to move quickly to slow the latest wave of COVID-19 infections to avoid a repeat of the broad lockdowns that paralyzed the continent's economy in the spring. 

EU health commissioner Stella Kyriakides said the most recent risk assessment showed that some countries are reporting more cases now than they did during the earlier pandemic's peak in Europe. 

"We are at a decisive moment. All member states must be ready to roll out control measures, immediately and at the right time, at the very first sign of potential new outbreaks," Kyriakides said. "This might be our last chance to prevent a repeat of last spring."

More than 3 million cases have been reported in Europe since the beginning of the year, including 187,509 deaths, according to figures from the European Center for Disease Prevention and Control. 

To control the virus's rebound, several EU nations have imposed localized lockdowns, limited public and private gatherings again, and restricted the operation of bars, restaurants and entertainment venues. 

European Center for Disease Prevention and Control director Andrea Ammon, noting the social impact of such moves, noted the need to maintain basic precautions such as physical distancing and frequent hand washing. 

"Until there is a safe and effective vaccine available, rapid identification, testing, and quarantine of high-risk contacts are some of the most effective measures to reduce transmission," Ammon said. 

Her agency said in its latest evaluation of the pandemic that the level of immunity in the European population remains low, estimating it is under 15% in most of the EU and the U.K.

"Most of the people can still be infected," Ammon said.

The ECDC said EU countries should emphasize curbing the spread of the virus among children and adults under age 50, making sure the public is aware that people in those categories can become seriously ill from COVID-19 as well as expose more vulnerable populations to the virus.

While some EU members have shortened their mandatory quarantine periods, the ECDC continues to recommended 14-day quarantines for people who had contact with infected individuals. 

"The pandemic is far from over and we must not drop our guard," Ammon said.