Outbreaks of disease are among the ultimate tests for any leader who wants to play on the global stage. They demand diplomacy, decisiveness, leadership, humility, and expertise—and they quickly unearth any lack of the same. “As far as I can tell, Trump has zero experience on this,” says Jack Chow from Carnegie Mellon University, who has worked at both the World Health Organization (WHO) and the State Department under Colin Powell. “If I asked him, ‘What is your stance on global health?,’ I don’t know what he’d say. I don’t think anyone really does.”

Bioethicist Art Caplan from the New York University School of Medicine envisages a quick slide towards isolation and authoritarianism. In a blog post that can only be described as pandemic fan-fiction, he imagines that a lethal mutant strain of H7N9 flu emerges in China and spreads to America. A hypothetical President Trump responds with a quick succession of moves: He seals the borders with Canada and Mexico; he quarantines sick Americans; he declares martial law, builds detention-style camps for quarantine-defiers, and uses epidemic conspiracies to launch a trade war with China.

Future years will reveal whether the story is prophetic or far-fetched. For now, we can only speculate, using the president-elect’s own words and actions to predict how he might fare in an outbreak.

We know that international diplomacy is essential during large-scale epidemics. During the Ebola outbreak, the U.S. had to coordinate its aid with the WHO, other donor countries, and hospitals and laboratories in the affected countries. “The rhetoric about building walls and reneging on NATO calls into question how willing the administration would be to work with other countries,” says Elizabeth Radin from Columbia University, who works to improve health in poor nations. “And the phone calls to Taiwan and Pakistan call into question how effective they would be.”

Accurate public communication is also vital. During the Ebola outbreak, misinformation circulated more widely than the virus itself. People repeatedly and wrongly heard that the virus could go airborne, that victims bleed dramatically from their eyes and ears, that foreign health workers brought the virus to West Africa, that folk remedies were effective, and so on. These were all myths, and they encouraged practices that helped the virus to spread in affected countries, while fomenting panic in unaffected ones. They resembled the pernicious and long-debunked claim that vaccines cause autism, which has led to a resurgence in mumps, measles, and other infectious diseases, and which Trump has himself promoted.

If anything, this problem is likely to get worse, given America’s continuing struggle to deal with “fake news.” Inaccurate information can be easily seeded by foreign parties, and given weight and prominence by online algorithms. It’s arguable whether such misinformation made a difference between victory or defeat in the election, but inarguable that it could mean life or death in an outbreak.