WHO head: 'Our key message is: test, test, test'

World Health Organisation head Tedros Adhanom Ghebreyesus says there has not been an urgent enough escalation in testing, isolation and contact tracing, which should be the "backbone" of the global response.

He said it is not possible to "fight a fire blindfolded", and social distancing measures and handwashing will not alone extinguish the epidemic.