The World Health Organization said Tuesday that the outbreak of the deadly novel coronavirus, which has spread from China to two dozen countries, does not yet constitute a "pandemic".
"Currently we are not in a pandemic," Sylvie Briand, head of WHO's Global Infectious Hazard Preparedness division, told reporters in Geneva.
Instead, she said, "we are at the phase where it is an epidemic with multiple foci."
The disease has killed more than 425 people and infected a further 20,000 in China, nearly all of them in central Hubei province -- the epicentre of the outbreak -- and spread to two-dozen countries since it emerged in December.
Briand said that while there is rapid spread of transmission in Hubei, outside the province there are mainly "spillover cases" with sporadic clusters of transmission.
"In these other places in China, the strategy currently is to stop transmission," she said, adding that the same was true for affected countries outside of China.
"We would like to make sure that we don't have a second Hubei type of scenario," she said.
Authorities in China have taken dramatic measures to halt transmission, while other affected countries have put in place steps to rein in the spread.
- Wearing mask 'not enough' -
"Countries are implementing early case detection, early isolation and treatment of patients, contact tracing to make sure they identify very early contacts that become symptomatic," Briand pointed out.
"We hope that based on ... measures in Hubei but also in other places where we have had spillover, we can stop transmission and get rid of this virus," she said.
She acknowledged that halting the spread of the new pneumonia-like virus would be "challenging".
"I am not saying it is easy, but ... we believe that it can be done," she said.
The respiratory disease spreads through droplets, for instance when people sneeze or cough, or likely through direct contact with infected people or with objects they have touched.
But Briand said it remained unclear how long the virus could linger on an object, stressing the need for frequent hand-washing to protect against transmission.
"To stop transmission of this virus, it is very important that sick people wear masks" to avoid infecting others, she said, adding though the benefits of healthy people wearing masks as a precautionary measure were less clear.
People wearing masks but not taking other precautions like frequently washing their hands could have a "false sense of security", she said.
"Masks alone are not enough. It is a package of measures that you have to put in place," she said.
"If people use the entire package, it is fine. If they just use masks, I think it is not enough."