The risk of a spike in infections is clearly present as some countries scrambled to restart their economies after easing stringent COVID-19 restrictions, a top health official has warned.

Michael Ryan, executive director of the World Health Organization's (WHO) emergencies program, expressed his concerns on Monday over the lifting of certain lockdown conditions that he reckons may lead to a resurgence of coronavirus cases.

"Shutting your eyes and trying to drive through this blind is about as silly an equation as I've seen.

"And I'm really concerned that certain countries are setting themselves up for some seriously blind driving over the next few months," he added.

His comments came as Germany, France, Spain, Italy, Belgium, the Netherlands and the UK relaxed restrictions in a bid to revive their almost stagnant economies.

Ryan praised Germany and South Korea for putting in place robust measures that would be able to trace and stop virus clusters before they get out of control.

Contact tracing involves a series of steps, which includes reaching out to people who tested positive, tracking down individuals they were in contact with and getting them quarantined. COVID-19 can spread before people start showing symptoms.

Check out The Pandemic Playbook, CGTN Europe's major investigation into the lessons learned from COVID-19