Dozens of new cases of the novel coronavirus are being identified almost daily. While it’s been called an “outbreak,” an “epidemic” and a “crisis,” the illness that’s sickened more than 17,000 people is not a pandemic — at least not yet.
The World Health Organization defines a pandemic as “the worldwide spread of a new disease.” The illness spreads around the world and typically affects a large number of people across a wide area.
So far, 2019-nCoV, as the new coronavirus is being formally called, doesn’t meet that definition.
“We would only call this a pandemic in the instance that there are multiple, ongoing chains of novel coronavirus transmission outside of China affecting a larger population,” says Dr. Isaac Bogoch, an infectious disease specialist based out of Toronto General Hospital.
“We’re not there yet.”
Cases of the novel coronavirus are increasing rapidly, but so far, the transmission of the influenza-like illness has been limited.
China is working around the clock to try and contain the virus. A 1,000-bed hospital dedicated to coronavirus patients was built in just 10 days. It is situated in China’s Hubei province, the epicentre of the outbreak, which has largely been quarantined from the rest of the country.
Other countries with cases — including Canada and United States — have issued high-level travel advisories about travel to China.
It’s too soon to say whether these measures will be enough, Bogoch said, or whether the outbreak will continue to evolve into a pandemic.
“Regardless, all efforts should be made to control this infection at the source while still preparing for the possibility that this may not be contained,” he said.
Compounding the fears of spread across borders is the possibility that the virus may be contagious before the infected person shows symptoms. If true, this would make it far more difficult to identify cases and could hinder containment. It would also call to question how effective tactics like quarantines are in this outbreak.
The transmissibility of the disease is part of the reason why researchers at the University of Hong Kong are calling for “substantial, even draconian, measures… that limit population mobility” in all virus-affected areas.
Their epidemiological model estimates the number of cases is much higher than what’s been reported so far — as many as 75,000 or more as of Jan. 25.
According to the Chinese government, the number of confirmed cases surpassed 17,000 in mainland China with more than 360 deaths as of Feb. 3.
The researchers have a few ideas about the reasons why there is a discrepancy in numbers: a lag in showing symptoms, people delaying getting medical treatment and the time it takes to confirm cases with lab tests.
“We have to be prepared that this particular epidemic may be about to become a global epidemic,” lead researcher and dean of the university’s faculty of medicine, Gabriel Leung, told the South China Morning Post.
But a top WHO official played down the concerns. He commended the efforts China is undertaking to try and suppress the spread, saying its allotted “precious lead time” for the rest of the world to prepare for its own response.
“That is not to say that the disease won’t get ahead of the Chinese authorities completely or get ahead of the other countries that are containing it,” Dr. Mike Ryan, who heads WHO’s Emergencies Program, told STAT News in an interview on Saturday.
“But there’s enough evidence to suggest that this virus can still be contained.”
The WHO defines “outbreak” as the “occurrence of disease cases in excess of normal expectancy.” An “epidemic” is defined as an “occurrence in a community or region of cases of an illness, specific health-related behaviour or health-related events clearly in excess of normal expectancy.” For an epidemic, the number of cases varies based on the size and type of population exposed, as well as time and place of occurrence, among other criteria.
A pandemic is considered a public health emergency by WHO. The agency declared the 2019-nCoV a public health emergency of international concern (PHEIC) on Jan. 30.
Few viral outbreaks have been given the PHEIC declaration in the past decade, including the 2009 H1N1 virus that caused an influenza pandemic, the Ebola outbreak in West Africa in 2014, the Zika virus in 2016 and the ongoing Ebola outbreak in the Democratic Republic of Congo.