The Trump administration’s campaign to slash the federal civil service hit one of the crown jewels of global public health on Friday. Members of the Epidemic Intelligence Service, a legendary training program run by the Centers for Disease Control and Prevention, were warned on Friday morning that they were about to be fired, two people with knowledge of the meeting told STAT.

The 135 members of the two-year program were informed that many would be hearing of their dismissals by late in the day. But by late Friday afternoon, none had yet received a notice of their firing, one of the sources said.

It is believed there will be a small number of exceptions: people who are in the Public Health Service and military officers who had been on the CDC staff before entering the program. Those two groups make up only a quarter of the current roster of EIS officers.

The EIS, as it is known, is the world’s premier training program for applied epidemiology. Many public health leaders at the CDC and elsewhere in the world are graduates of the EIS, which was established in 1951 by the CDC’s then-chief epidemiologist Alexander Langmuir, in part because of Cold War era concerns about the threat of germ warfare.

EIS officers make up the frontline in public health emergencies, both in the United States and abroad. When a difficult disease outbreak hits, when state health departments need assistance tracing the source of foodborne illnesses, EIS officers are dispatched. They were among the first responders when letters laced with anthrax were mailed to legislators and news outlets around the country in 2001. They were even portrayed on the big screen: In the 2011 Steven Soderbergh movie Contagion, about the start of a pandemic, Kate Winslet’s character was an EIS officer sent to investigate the unnerving new disease that an American businesswoman had unwittingly transported to Minneapolis.