Europe is suffering a demoralizing rise in COVID-19 cases after driving down its confirmed case numbers to their lowest in early June. This success led European Union member states to reopen borders to intra-Europe trade and travel starting July - a decision said to have contributed to the recent increases.

The number of new COVID-19 cases in Europe increased 5.6 percent to more than 4 million cases from June 7 to the week ended Aug. 23, according to data from the World Health Organization.

This represents a 6 percent week-on-week jump and an increase of 72 percent compared with the week ended June 7 - which saw the lowest number of weekly infections.

More than half of the new cases in the week ended Aug. 23 came from four countries: Spain (21 percent), Russia (16 percent), France (10 percent) and Ukraine (6 percent). Spain has seen close to 463,000 coronavirus cases. Russia's number of confirmed cases rose to more than 1 million Tuesday.

The 14-day case notification rate for the EU, the European Economic Area and the UK was 46 per 100,000 people as of Aug. 26, said the European Center for Disease Prevention and Control. The rate has been increasing for the past 38 days. The Center for Disease Prevention said the COVID-19 mortality rate for the EU, European Economic Area and the UK was four per million people. The rate has been stable for 53 days.

In its latest risk assessment, the center said the risk of further escalation in infections was "high" in countries that had reported an increase in hospitalizations. This outcome is a strong indication there is a genuine increase in transmission occurring in these three areas.

The center said the risk of escalation was "very high" for countries if they failed to reinforce health policies such as physical distancing, contact tracing and testing.

WHO said a relaxation of public health measures, and people "dropping their guard," helped explain the resurgence of the virus across Europe.

"WHO fully supports efforts to reopen economies and societies," Director-General Dr. Tedros Adhanom Ghebreyesus said. "We want to see children returning to school and people returning to the workplace - but we want to see it done safely."

He also said no country can just pretend the pandemic is over. The reality countries must accept is that COVID-19 spreads easily and "can be fatal to people of all ages and most people remain susceptible."

The U.S. is suffering even more. It exceeded 6 million confirmed cases Tuesday and has reported more than 184,000 deaths - the worst in the world in both categories. The rolling seven-day average of daily cases per million people showed the U.S. with almost 20 times as many cases as the EU.