The CDC is not the only affected agency. USAID also received $300 million from the same dwindling pot of money, which it used to expand its work in the Middle East and Asia. Those programs may also have to shut down in 2019.

These changes would make the world—and the United States—more vulnerable to a pandemic. “We’ll leave the field open to microbes,” says Tom Frieden, a former CDC director who now heads an initiative called Resolve to Save Lives. “The surveillance systems will die, so we won’t know if something happens. The lab networks won’t be built, so if something happens, we won’t know what it is. We can’t be safe if the world isn’t safe. You can’t pull up the drawbridge and expect viruses not to travel.”

The $1 billion of Ebola money was used under the umbrella of the Global Health Security Agenda—a five-year international partnership to improve the health security of developing nations. Barack Obama convened the GHSA in 2014 with strong bipartisan support, and it has already made a significant difference.

Thanks to the GHSA, Uganda now has a secure lab for studying dangerous germs. Tanzania has a digital communications network so people can phone in information on potential outbreaks from remote locations. Liberia has more than 115 frontline disease detectives trained by the CDC. Cameroon shortened its response time to recent outbreaks of cholera and bird flu from 8 weeks to just 24 hours. The DRC controlled an outbreak of yellow fever and built an emergency operations center (EOC)—a kind of war room for responding to outbreaks. But there is still much to do: The DRC, for example, still needs to train staff to run its EOC.

Last October, at a meeting in Kampala, Uganda, Tim Ziemer, the White House senior director for global health security, confirmed that the United States wants to ensure that GHSA is extended to 2024. “Distance alone no longer provides protection from disease outbreaks,” he noted. “We recognize that the cost of failing to control outbreaks and losing lives is far greater than the cost of prevention.” (Ziemer’s leadership is a promising sign for the public-health community, given his redoubtable credentials: He led George W. Bush’s President’s Malaria Initiative, and has been described as “one of the most quietly effective leaders in public health.”)

But that verbal commitment hasn’t yet been followed by a financial one. It is entirely possible that the next budget, which is due to be issued on February 12, will include money for the GHSA. But the uncertainty has already forced the CDC to begin preparing for potential pullbacks. Damage is already being done. “The reality is that people have to prepare and live their lives,” says Linda Venczel, from PATH, a nonprofit working in global health. “People are packing their bags and looking for other jobs. Things will unravel pretty quickly.”