In the wake of the month-long coronavirus outbreak that has infected more than 7,700 people and killed 170, the World Health Organization (WHO) has declared a global emergency today (January 30).
What does this mean?
According to the WHO web page on international health regulations (IHR), a public health emergency of international concern (PHEIC) is an "extraordinary event" that constitutes a "public health risk to other States through the international spread of disease". It also might require "a coordinated international response" that might include "immediate international action".
PHEICs have been invoked in the past for the H1N1 (swine flu) virus outbreak in 2009, the Ebola virus outbreaks of 2019 and 2014, the Zika virus in 2016, and the polio virus in 2014 after a rise in the number of cases worldwide the year before after the disease was thought to be near eradication globally.
Recommended measures for the affected countries are meant "to prevent or reduce the international spread of disease and avoid unnecessary interference with international traffic". (China, the source of the outbreak, has already quarantined at least 16 cities—including Wuhan, where the virus was first detected on December 31, 2019—with a total population of about 50 million people. Canada and other countries are making plans to evacuate citizens caught in China when travel restrictions were put into place recently.)
Once the WHO's emergency committee declares a PHEIC, it can issue travel advisories to help countries affected by the outbreak. It can also advise on the public-health steps taken by affected countries.
Although the WHO cannot enforce any of its recommendations, countries that are members of the organization are bound by signed agreement, and international pressures can be brought to bear on states that refuse to abide by advisories because of political and/or economic reasons.
The WHO's FAQ for its most recent (2005, two years after the global SARS outbreak) IHR has this to say about member-state compliance: "Perhaps the best incentives for compliance are 'peer pressure' and public knowledge. With today's electronic media, nothing can be hidden for very long. States do not want to be isolated. The consequences of non-compliance may include a tarnished international image, increased morbidity/mortality of affected populations, unilateral travel and trade restrictions, economic and social disruption and public outrage."
Member states are responsible for implementing all WHO regulations proclaimed during a PHEIC.