Municipal workers wait before spraying insecticide at Sambodrome in Rio de Janeiro, in this Jan. 26 photo. (Pilar Olivares/Reuters)

The World Health Organization jumped into action on the Zika outbreak in 2016. That’s in sharp contrast with the WHO’s much slower response to the Ebola outbreak in 2014. Political science research on international organizations and on how issues are framed can help explain the difference.

Slow with Ebola, fast with Zika

The WHO confirmed an Ebola outbreak in March 2014. Five months and nearly 1,000 deaths later, the WHO announced that the West African Ebola outbreak was a Public Health Emergency of International Concern (PHEIC).

This was only the WHO’s third PHEIC declaration, after the 2009 H1N1 influenza pandemic and polio’s resurgence in 2014. After the Ebola PHEIC delaration, donors mobilized financial and military resources, and the U.N. Security Council created the U.N. Mission for Ebola Emergency Response. Public health officials and policymakers found the time lag inexplicable, given the WHO’s scientific knowledge and experience with Ebola in Uganda and the Democratic Republic of Congo.

In contrast, the WHO quickly flagged Zika as a PHEIC, despite significantly fewer deaths. More precisely, the third Zika-related death in Brazil — the epicenter of the current outbreak — was recorded 10 days after the PHEIC announcement. Zika may have already infected more than 1 million people. Most have recovered, and an estimated 80 percent do not experience symptoms. The WHO’s PHEIC declaration was intended to jump-start scientific research, vaccine and treatment development, and mosquito-control campaigns.

WHO officials blamed the slow Ebola response on budget cuts that hit programs on infectious disease control and on poor communication between Ebola-affected countries and WHO headquarters in Geneva. Despite ongoing budget pressures, in 2016 the WHO said that the need for greater scientific knowledge on Zika drove its PHEIC announcement. And surely the WHO, after being accused of dragging its feet with Ebola, wanted to act quickly with Zika.

Political scientists would argue that the story is still more complicated. In “Rules for the World,” Michael Barnett and Martha Finnemore show that international organizations’ internal workings and technical expertise influence their actions in ways that are sometimes at odds with the goals of the countries that set up these organizations to work on their behalf.

1. The WHO has six autonomous regional offices that behave differently

The WHO is not a monolith. It does not always behave uniformly across its six regional offices, each of which is autonomous. The organization’s internal dynamics matter when it comes to launching an urgent health initiative. In the Zika case, the Pan-American Health Office (PAHO), a regional WHO office, had expertise on mosquito-transmitted diseases such as dengue and chikungunya fever, which legitimated its call for more WHO action. PAHO, the oldest WHO regional office, also showed the professionalism needed to bump up the Zika response. With its close links with the United States, PAHO could put into place the disease-control measures needed to respond to Zika.

In contrast, the WHO’s African Health Office (AFHO) was relatively ineffective against Ebola. That was in part because of its culture of cozy political relationships and inefficiency and in part because it wasn’t as well funded or staffed.

2. The WHO cares about its reputation among powerful countries 

International organizations, such as the WHO, also care about their reputations with states, because these reputations shape trust, legitimacy and, ultimately, resources. By acting swiftly on Zika, the WHO may be trying to rebuild the reputation for efficiency and decisiveness that it gained when responding to the severe acute respiratory syndrome (SARS) pandemic in 2003 — but then lost during the Ebola crisis.

The WHO is also influenced by how powerful nations’ populations and policymakers — such as those of the United States — perceive particular health issues. For those states, Ebola was a distant threat in the world’s poorest region.

Zika cases, on the other hand, appeared quickly throughout the Western hemisphere, with Brazil predicted to soon have over 2,500 microcephaly cases. With summer approaching, the United States may soon see its own Zika cases. And the long-term costs of caring for microcephalic children will be high.

Political scientist Adam Kamradt-Scott shows how the WHO’s autonomy has historically vacillated, depending on nations’ interests. The WHO’s early PHEIC declaration on Zika may reflect pressures from both the United States and Brazil.

Indeed, the WHO seemed to follow the Centers for Disease Control and Prevention and several countries’ health ministries when on March 8 it advised pregnant women to avoid traveling to Zika-affected countries. Brazil and the United States showed theWHO scientific evidence linking microcephaly and Zika, and Brazil and other Latin American states called for more global funding for Zika. Zika could hamper Brazil’s attempt to be taken seriously as an emerging global power, with a strong economy and responsive state services.

3. The message matters

There’s a final point to understand. Health issues are more likely to become global political priorities when they are conveyed in a way that resonates with an audience of policymakers and citizens. This “framing” may have little to do with how much that mortality, morbidity or disability come from that disease. If it did, cardiovascular diseases and mental illnesses would be much higher health priorities.

Margaret Keck and Kathryn Sikkink show that issue frames that stress the prevention of bodily harm for vulnerable or innocent groups may sway policymakers. Newborns that have developed microcephaly from Zika-infected mothers stand for innocence and vulnerability.

While Ebola had high mortality rates and caused intense suffering, it infected wide swaths of society, making it harder to frame the need for action around a particular group. What’s more, Ebola aligned with what Priscilla Wald terms the “outbreak narrative.” That’s the conventional view that poor countries have disease outbreaks, and that powerful states only care about those outbreaks when their spread threatens those states. Zika hit far closer to powerful countries — and hit “threat perception” level before Ebola.

In deciding how to respond to outbreaks, global organizations and the states that support them should realize that how those diseases are framed matters.

Amy S. Patterson is a professor of politics at the University of the South.