The new coronavirus that's sickened tens of thousands of people in Asia is not yet a pandemic, but has the potential to become one if countries don't work together to slow its spread, the World Health Organization said Monday.
Concern about possible widespread global infection has increased in recent days, as cases have risen significantly in countries other than China, including Iran, Italy and South Korea, prompting some experts to warn that the coronavirus is already at pandemic levels.
However, the WHO urged preparedness over panic.
"Does this virus have unlimited potential? Absolutely," WHO Director-General Dr. Tedros Adhanom Ghebreyesus said during a media briefing. "Are we there yet? From our assessment, not yet."
While the country-to-country spread may meet a dictionary's definition of the word "pandemic," the WHO's restraint in naming it is based on an ongoing assessment of how far the virus has spread around the world, how severe the disease is and the "impact it has on the whole society," Tedros said.
"For the moment, we are not witnessing the uncontained global spread of this virus, and we are not witnessing large-scale severe disease or death," he said.
Dr. Colleen Kraft, who was part of the team at Emory University Hospital in Atlanta that successfully treated several Ebola patients in 2014, told NBC News the one thing communities can do is "not panic."
"We're not talking about Ebola. We're not talking about something that has a high mortality rate for just anybody," she said.
In fact, the WHO no longer uses the pandemic classification. The shift from declaring a pandemic stems from the 2009 H1N1 swine flu pandemic, which turned out to be mild, leading to some criticism after pharmaceutical companies rushed development of vaccines and drugs. On Jan. 30, WHO declared the novel coronavirus that emerged in Wuhan, China in December a public health emergency of international concern, known as a PHEIC.
Full coverage of the coronavirus outbreak
"Epidemiologic words don't really matter" from a bio-preparedness perspective, Kraft said. "It's more about what we need to do in response to it at our health care level or at our personal level."
A PHEIC is the WHO's highest level of alarm anyway, and is designed to coordinate global outbreak efforts and help vulnerable countries with weaker health systems shore up their defenses, especially in Africa.
Johns Hopkins public health expert Lauren Sauer says the rapid rise of new cases outside of China indicates a pandemic is already happening. But she understands the WHO's hesitation to escalate the global warning.
"If we stick to what we know a pandemic is in a general sense, we can all agree that it is concerning, but in reality what we’re talking about is the geographic spread of a virus," Sauer, director of operations for the Johns Hopkins Office of Critical Event Preparedness and Response, told NBC News."This definition allows us to move past this idea of containment and towards mitigation strategies that the whole world can apply and benefit from."
Slowing down the virus
The WHO said that if countries can throw a collective cog in the coronavirus wheel, it can help delay burdens placed on health care systems currently spread thin by flu season. There have been an estimated 26 million flu illnesses in the U.S. alone this season.
"Even slowing down the virus by a month or six weeks has massive positive benefits on the system," Mike Ryan, executive director of the WHO's Health Emergencies Program, said during the press briefing Monday.
A WHO-led group of scientists has wrapped up a trip to Wuhan, China, the center of the outbreak that's sickened more than 77,000 people. The team is scheduled to offer a full report Tuesday.
But Tedros provided a few early details. Inside of Wuhan, the fatality rate is between 2 percent and 4 percent.
In China, more than 2,600 people have died. For perspective, that's 1,000 more deaths than two other major coronavirus outbreaks — SARS and MERS — combined.
Tedros said that elsewhere in the world, the fatality rate for the new coronavirus is much lower, at 0.7 percent. The mortality rate for seasonal flu is even less, usually around 0.1 percent.
About 80 percent of coronavirus cases are said to be mild. Those patients generally feel better within about two weeks, Tedros said.
But more severe cases can take up to six weeks for recovery. The elderly and people with compromised immune systems have been most vulnerable to serious health effects.
The WHO-led team also found that the epidemic in China appears to have peaked sometime between Jan. 23 and Feb. 2, before declining steadily. That gives health officials encouragement that epidemics in other countries could be managed.
More than 77,000 people in China have fallen ill with COVID-19, the illness that's caused by the coronavirus. And more than 2,600 people have died there.
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