Tedros Adhanom Ghebreyesus, director general of the World Health Organization (WHO), speaks during a news conference on the COVID-19 coronavirus outbreak in Geneva, Switzerland, on Monday, March 2, 2020.

World Health Officials said on Friday that the coronavirus appears to be slowing in some of the hardest-hit countries in Europe like Spain, Italy, Germany and France, however, lifting stay-at-home orders too soon could lead to a "deadly resurgence."

"[The] WHO wants to see restrictions lifted as much as anyone. At the same time, lifting restrictions too quickly could lead to a deadly resurgence. The way down can be as dangerous as the way up if not managed properly," WHO Director-General Dr. Tedros Adhanom Ghebreyesus said.

WHO declared Europe the new epicenter of the disease in March after cases in China, where the pandemic began nearly four months ago, started to slow.

Spain, which is the second hardest-hit country behind the U.S., has more than 157,000 confirmed cases of coronavirus, according to Johns Hopkins University data. Italy, which has the most reported deaths than any country globally, has more than 143,600 confirmed cases. The coronavirus has infected more than 467,100 people in the U.S. and 1.6 million people globally.

There's been an "alarming acceleration" of cases in other countries, especially in Africa, Tedros said. He said that the WHO is now seeing clusters of cases and community spread, where the virus spreads without a known source, in more than 16 countries in Africa, which poses a threat to already overstretched health-care systems.

Tedros added that the WHO is especially concerned about the high level of health-care workers infected across the globe. He said that in some countries, reports indicated up to 10% of health workers are infected with COVID-19.

He said that evidence from some countries, including the U.S. and China, show that some health-care employees are being infected outside health-care facilities. Within the facilities, some personnel are also undertrained and inexperienced when dealing with respiratory pathogens, like the coronavirus, and they're exposed to large numbers of infected patients with inadequate breaks.

"This is an alarming trend. When health workers are at risk, we're all at risk," Tedros said.

Before social distancing restrictions can be lifted, Tedros said each country needs to consider whether the virus' transmission is controlled, if sufficient medical services are available and if outbreak risks in special settings like long-term care facilities are minimized. He said that preventive measures must also be in place in workplaces and schools and that communities are fully aware during the transition.

"Countries who relatively have the strongest health system have been actually surprised by this pandemic," Tedros said. "It shows that any system could have gaps and we should have the humility to see to what extend our system is prepared, where are the gaps and how we can improve it for the future."