Dr. Maria Van Kerkhove, the technical lead for coronavirus response at the World Health Organization, has warned the virus is resurging in several parts of the world.
Speaking during CNN's ongoing town hall tonight, she said places that have seen some success in suppressing transmission are now experiencing a second wave of infection, pointing to South Korea, Singapore, and Wuhan -- the Chinese city at ground zero for the pandemic.
There are different reasons we're seeing a resurgence of the virus in these places, she said; in South Korea, a new cluster in Seoul is linked to nightclubs, while Singapore's outbreak is largely concentrated within migrant worker dormitories.
"But what is really important is that in China, in Korea, in Singapore, they have systems in place to rapidly identify the virus again and rapidly start their contact tracing," Van Kerkhove said.
"And they've never let up. This is a lesson for all countries. The virus likes to find opportunities to resurge, to increase again. And we just all need to be ready for that."
The US risks a second wave if it rushes into reopening: Though infection rates are slowing in the United States, individual states should conduct a thorough assessment before reopening, Van Kerkhove said.
"What is the risk of resurgence? Do we actually have this under control? Are we looking hard enough? Do we have surveillance in place? Do we have contact tracers in place? Do we have hospital beds? If the answer is no, then you need to really consider, are we ready to open this up?" she said.