As cases of the diarrhea-causing parasite cyclospora rise across the US, former employees of the Centers for Disease Control and Prevention say the country’s response is being severely hampered by personnel cuts at the agency.

Amid mass government layoffs last year implemented by President Donald Trump and his so-called Department of Government Efficiency, the CDC lab that responds to outbreaks of the parasite cyclospora was downsized from 11 people to just three, according to Joel Barratt, a molecular parasitologist and assistant professor at Emory University School of Medicine who previously led that team.

“Based on simple math, these outbreak responses—which require rapid, timely responses—are going to be greatly diminished,” he tells WIRED. “Cyclospora is just one piece. It’s making the news right now, but there are other, more dangerous pathogens than cyclospora.”

Barratt says he left the CDC voluntarily in September after working at the agency for eight years because he felt he could no longer “do right by public health” amid sweeping policy overhauls and staff purges under Health and Human Services secretary Robert F. Kennedy Jr.

“It became a hostile work environment,” he says. “I had to sit down with many people in my office and tell them, ‘Look, I’m really sorry we can’t renew you because of the hiring freezes.’”

WIRED reported in October that the CDC reduced its total workforce by about 3,000 employees—roughly a quarter of the agency—since January 2025. That number includes layoffs, as well those who accepted the Trump administration’s buyout program. The estimate was compiled by the American Federation of Government Employees Local 2883, which represents CDC workers. The size of the cuts at Barratt’s former lab was first reported by Nature.

An HHS spokesperson did not respond to a request for comment.

Nearly 7,000 people across the country may have been sickened with cyclospora, although experts say that number is almost certainly higher. As of Thursday, Michigan alone has identified more than 4,300 cases.

The CDC is also being stretched thin by a wave of public health crises. Amid the staffing reductions, the agency is also responding to a major Ebola outbreak in the Democratic Republic of Congo, as well as several US outbreaks including measles; E. Coli linked to frozen blueberries; infant botulism found in certain powdered infant formula; and salmonella from several sources. The CDC is working on pinning down the source of the cyclosporiasis outbreak and has identified lettuce from Taylor Farms as a possible source, anonymous sources told The Washington Post.

“Even before the cuts of 2025, we’ve known that our public health surveillance systems and our food safety systems leave a lot to be desired,” says Amira Roess, a professor of global health and epidemiology at George Mason University and a former CDC epidemic intelligence service officer.

Barratt says responding to disease outbreaks is a complex process that involves lots of coordination between states and the federal government.

Cyclospora comes with its own set of challenges, particularly the lag time between when someone is initially exposed to a contaminated food product and the onset of sickness. Symptoms can take a week or two to appear, and people who get sick may not seek medical care for several days after that, if at all.

Once a stool sample tests positive for cyclospora, it’s sent to that state’s health department for analysis, which then passes it to the CDC for genetic testing. At the same time, epidemiologists at the state health department reach out to the patient for an interview, which is designed to identify what the person ate within the past two weeks. That information is also sent to the CDC, where epidemiologists look for commonalities among reported cases.

Meanwhile, the CDC’s lab for parasitic diseases performs genetic testing on the parasites in the stool sample. This can identify patients who are infected with the same strain of cyclospora—information that CDC epidemiologists use to determine disease clusters, groupings of illness related by time, geographic location, or common exposures.

“When it comes to investigating outbreaks, we have a lot of the techniques down,” Roess says. “We know what to do, but if we don’t have personnel, a lot of it can’t get done.”