On January 30, the World Health Organization (WHO) declared the new coronavirus outbreak that emerged in China in December a Public Health Emergency of International Concern (PHEIC). Over 73,000 cases of the disease, known as Covid-19, have been confirmed worldwide as of February 18. In a striking move, some 60 countries have imposed travel restrictions on visitors from China or tightened visa requirements in order to slow the outbreak’s spread. Major commercial airlines have also suspended flights to China, including American Airlines, Air France, and British Airways.

However, the WHO has advised countries not to restrict travel and trade with China, in accordance with the 2005 International Health Regulations (IHR), a binding international treaty. In addition, a chorus of independent experts have argued that travel restrictions are of “limited effectiveness” in containing the outbreak. They can even be counterproductive by generating substantial economic losses and preventing the transfer of much-needed goods and services, such as medicines and personal protective equipment, which are in short supply in China.

The debate over Covid-19-related travel bans represents one of several policy disagreements that have emerged in recent weeks over the most effective way to respond to the novel pathogen, whose transmission patterns and severity of illness remain uncertain. While governments around the world have implemented drastic measures in response to the outbreak, many of these appear inconsistent with available scientific evidence, independent expert opinion, and WHO guidance. As panic spreads along with the outbreak, will evidence-based public health prove to be its biggest victim?

On February 15, WHO Director-General Tedros Adhanom Ghebreyesus reminded WHO member states that approaches to controlling the outbreak must be “guided by evidence and public health priorities.” He warned, “Now more than ever is the time for us to let science and evidence lead policy. If we don’t, we are headed down a dark path that leads nowhere but division and disharmony.”

Experience from past pandemics suggests response activities are frequently at odds with scientific or expert opinion. During the 2014-16 Ebola outbreak in West Africa, 43 countries prohibited the entry of foreigners who had recently visited a country with widespread Ebola transmission, in violation of the IHR. Another oft-cited example is Egypt’s culling of 300,000 pigs in 2009 to prevent the spread of H1N1 influenza (“Swine Flu”), despite no evidence that the virus could be spread by pigs or eating pork products.

Quarantines Questioned

Arguably the most controversial of current approaches has been the widespread use of quarantines (i.e., separation of healthy individuals who have been exposed to the virus). In an unprecedented move, China has placed Wuhan, the epicenter of the outbreak, under cordon sanitaire­ by preventing its 11 million inhabitants from entering or exiting the city. As many as 760 million people across China are under some form of residential lockdown, according to a New York Times analysis. The government has also required travelers returning to Beijing to self-isolate for 14 days.

While this may not be surprising for China, even democratic countries have enacted strict quarantine policies. The United States’ Centers for Disease Control and Prevention (CDC) imposed a mandatory, 14-day quarantine on more than 800 Americans who returned from China’s Hubei province, including 200 held at a military base in California. Similarly, Australia quarantined 270 citizens and permanent residents who were evacuated from China for 14 days on Christmas Island in the Indian Ocean. Other countries have adopted quarantines as well, including Japan and Russia.

In a February 5 briefing, the CDC stated that these and other movement restrictions are needed to “slow the introduction and impact” of the virus in the US. However, numerous independent experts have questioned the efficacy of quarantines and other social distancing measures.

On February 12, independent public health experts, including former US Ebola Response Coordinator Ron Klain, testified before the US Congress that, in today’s interconnected world, quarantines and other travel bans are unlikely to be effective in preventing transmission of the virus to the US (which some believe may already be circulating in the population). A recent editorial in the Journal of the American Medical Association argued that while US quarantines may be legally justified, there are “less-restrictive alternatives” that would uphold civil rights, including enhanced patient screening, active monitoring, and house arrest.

My colleagues and I at the Johns Hopkins Center for Health Security argued in a recent report, “Preparedness for a High-Impact Respiratory Pathogen Pandemic,” that there is currently a “broad lack of evidence of efficacy and a lack of understanding about secondary adverse impacts” of quarantines and other non-pharmaceutical interventions. For example, they could lead to harm by stigmatizing vulnerable populations and make people more likely to hide away or conceal their health status from authorities.

This occurred in Hong Kong during the 2003 SARS epidemic, when residents fled an apartment complex under lockdown before police arrived, effectively driving the disease underground. Last week, in a concerning trend, multiple people across Russia escaped from quarantines by breaking locks and fleeing from police. Quarantines require strict adherence and work best when government and law enforcement have a trusting relationship with the public.

WHO Under Scrutiny

Interestingly, the WHO has been silent with regards to domestic quarantine measures, even as it condemns international travel bans. In fact, Tedros has repeatedly praised China’s domestic response to the outbreak, stating on February 15 that he was “encouraged [by] the steps China has taken to contain the Covid-19 outbreak at its source.” This is despite revelations that Chinese officials may have suppressed internal warnings about the disease’s emergence while not being fully transparent with the international community about the actual number of cases.

As others have argued, this stance likely reflects WHO’s desire to stay on good terms with the Chinese government, a major WHO stakeholder, while avoiding interfering in a national sovereignty issue that is beyond the agency’s purview. However, this has also exposed the agency to criticism. As reported by the Wall Street Journal, Tedros has been accused of playing politics by being overly deferential to China. Critics point to his January 23 decision to rule against declaring the Covid-19 outbreak a PHEIC after the WHO Emergency Committee, an independent group of experts tasked with advising him, was divided. A public health emergency was declared the following week instead, but the delay baffled some experts.

In response to the incident, an online petition signed by nearly 400,000 people has called for Tedros’ resignation for “underestimating” the outbreak and for not remaining “politically neutral.” While it remains to be seen if the WHO acted appropriately, the incident underscores the challenge of making public health decisions at the intersection of science of politics.

Moving forward, the international community will need to ensure that public health interventions to control the Covid-19 outbreak are evidence-based and not influenced by external and domestic political pressures, especially amid a climate of fear and uncertainty. While there is broad consensus on the need for enhanced surveillance and screening measures, many have questioned the public health necessity of sweeping movement restrictions that are likely to result in unforeseen consequences, potentially doing more harm than good.

In addition, compliance with WHO recommendations on travel and trade restrictions under the IHR can be strengthened by naming, publicly, those nations that undermine them. The WHO can also safeguard its credibility by revisiting reform of the PHEIC declaration process to return decision-making power to independent scientific experts and away from the director-general—a recommendation that has been made previously. Finally, it is vital that the WHO, in partnership with academia and public health, launch a research agenda to capture data from the response to the Covid-19 outbreak to determine when and under what conditions quarantines and travel bans may actually be effective at limiting the spread and severity of outbreaks.