The case fatality rate is between 2% and 4% inside the city of Wuhan, the epicenter of the outbreak, and 0.7% outside of Wuhan, Tedros said, citing the team's findings. For people with mild diseases, recovery time is two weeks, while people with severe or critical diseases recover in three to six weeks, he said.

A WHO-led team of scientists that just returned from China found that the epidemic in that country peaked and plateaued between Jan. 23 and Feb. 2 and has been declining steadily since then, Tedros Adhanom Ghebreyesus, director-general of WHO, said at a news conference at the agency's headquarters in Geneva.

The COVID-19 outbreak in China appears to have peaked and leveled off earlier this month even as the deadly coronavirus spreads to other parts of the world, World Health Organization officials said Monday.

While cases in China have slowed, the "sudden increase in new cases" outside of the country is "deeply concerning," Tedros said. Outside of China, there are 2,074 cases across 28 countries, including 23 deaths, he said.

"What we see is epidemics in different parts of the world, affecting countries in different ways and requiring a tailored response," Tedros said.

The exact timing of when cases in China peaked is unclear. While WHO said cases in China peaked and plateaued mostly in late January, the organization's own data appears to show that cases leveled off sometime during the week of Feb. 14.

The reason for the apparent discrepancy could be because China changed the way it classifies cases three times, said Isaac Bogoch, an infectious disease specialist and professor at the University of Toronto.

"It's hard to look at the data and derive definitive conclusions, given the definition of cases has been changed several times," he said. "Whether or not it peaked at that time or another time, the key point is that it does appear to be peaking and plateauing now."

Localized outbreaks of the virus in Iran and Italy are fueling concerns among infectious disease experts and scientists that the virus is spreading too quickly and may be past the point of containment.

Earlier in the day, health officials reported a seventh death in northern Italy, while the number of confirmed cases rose to more than 220 in the country. In Iran, officials confirmed 61 total cases in the country as of Monday, with 12 deaths nationwide.

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.

WHO officials on Monday declined to declare the virus a pandemic, saying now is the time to focus on containment, not language.

"This is the time for all countries, communities, families and individuals to focus on preparing," Tedros said.

U.S. health officials said they are preparing for the coronavirus to become a pandemic.

"We're not seeing community spread here in the United States, yet, but it's very possible, even likely, that it may eventually happen," Dr. Nancy Messonnier, director of the CDC's National Center for Immunization and Respiratory Diseases, told reporters on a conference call Friday. "Our goal continues to be slowing the introduction of the virus into the U.S. This buys us more time to prepare communities for more cases and possibly sustained spread."

There are currently no proven therapies for the virus and a vaccine will take at least a year to develop, health officials say.

Tedros said last week that preliminary results from two clinical trials testing potential treatments for COVID-19 are expected in three weeks.

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