Regional director Dr Hans Kluge said that there have been “very significant resurgences” in coronavirus infections in 11 European countries, which he did not name.
Dr Kluge told reporters in a virtual press conference: “For weeks, I have spoken about the risk of resurgence as countries adjust measures.”
“In several countries across Europe, this risk has now become a reality — 30 countries have seen increases in new cumulative cases over the past two weeks.
“In 11 of these countries, accelerated transmission has led to very significant resurgence that if left unchecked will push health systems to the brink once again.”
WHO figures show the European region recording 20,000 new coronavirus cases and more than 700 deaths linked to the virus each day.
The region covers 54 countries, including the Middle East and Central Asia. More than 2.6 million infections have been reported overall, with around 195,000 deaths.
Many European countries have gradually begun lifting lockdown measures over the past two months, while pledging to bring back restrictions if cases spike sharply.
Dr Kluge praised countries like Poland, Germany and Spain for their fast responses to outbreaks linked with schools, coal mines, and food production, which helped bring the new batch of cases under control.
He added that the WHO believes coronavirus infection rates be less high over the summer, but warned that countries should prepare for the virus to bounce back in autumn.
Dr Kruge went on: “We have indeed to prepare for the [autumn], when Covid-19 may meet seasonal influenza, pneumonia, other diseases as well, because ultimately the virus is still actively circulating in our communities and there is no effective treatment, no effective vaccine, yet.