People are wearing masks at Myeongdong on February 20, 2020 in Seoul, South Korea.

Jong-Hyun Kim |Anadolu Agency | Getty Images

As cases of the new coronavirus surge outside of China, world health officials said Monday that other countries should start preparing for epidemic outbreaks of COVID-19 to cross their borders.

“It is time to do everything you would do in preparing for a pandemic,” Dr. Mike Ryan, executive director of the World Health Organization’s health emergencies program, told reporters at a news briefing at the organization’s headquarters in Geneva. “In declaring something a pandemic, it is too early. We’re still trying to avoid that eventuality.”

In the past week, the virus has spread substantially outside of China. In Italy, the virus has infected more than 220 people and killed at least seven as of Monday morning. South Korea confirmed another 231 cases on Monday, which brings the total in the country to more than 830. And health officials in Iran have confirmed 61 total cases in the country, with 12 deaths nationwide.

The localized outbreaks outside of China are fueling concerns among infectious disease experts and scientists that the virus has become a pandemic. However, WHO officials declined to declare it as one on Monday, saying that it is still too early to say.

“Pandemos is a concept where there’s a belief that the whole world’s population would likely be exposed to this infection and potentially a proportion of them fall sick and we’ve seen that in influenza,” Ryan said, citing the Greek root of the word pandemic.

He said influenza pandemics can be called much earlier and easier because they know how that virus spreads.

World health officials don’t entirely understand how COVID-19 spreads, Ryan said, but the fact that new cases in China have dropped “goes against the logic of pandemic.” A WHO-led team just concluded a research trip to several provinces in China, including the epicenter of the outbreak, Wuhan in Hubei province. WHO’s director-general, Tedros Adhanom Ghebreyesus, said the team reported that cases “peaked and plateaued” between Jan. 23 and Feb. 2 and have been “declining steadily since then.”

“Yet we see, in contrast to that, an acceleration of cases in places like Korea and therefore we’re still in the balance,” Ryan said.

Globally, the outbreak has now infected more than 79,400 and killed at least 2,600 so far.

“If we’re not using the P-word now, we’ll be using it in the days or weeks to come,” Isaac Bogoch, an infectious disease specialist and professor at the University of Toronto, said in a phone interview with CNBC. The data from China indeed shows a peak and decline, he added, but there are questions about the reliability of that data.

On Sunday, Chinese President Xi Jinping called the outbreak a major public health emergency with “the fastest spread, the widest range of infections, and the most difficult prevention and control in China” since the founding of the People’s Republic of China, according to state media.

Outside China, there are now 2,074 cases in 28 countries, including 23 deaths, Tedros said. He said the sudden increase in cases in Italy, Iran and South Korea is “deeply concerning.”

“Does this virus have pandemic potential? Absolutely it has. Are we there yet? From our assessment, not yet,” Tedros said. “This is not the time to focus on what word we use. That will not prevent a single infection today or save a single life today.”

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