More than 3,000 public health workers have left the CDC through firings, forced retirements and attrition. This workforce reduction, combined with a downgrade in active surveillance for the parasite Cyclospora cayetanensis, has contributed to a massive outbreak of cyclosporiasis in the United States this summer.
Outbreak scale and surveillance changes
As of 15 July, the CDC had confirmed 1,645 domestically acquired cases across 34 states, with 141 hospitalizations. The agency is aware of more than 5,100 further cases awaiting analysis. Michigan, which typically records 40 to 50 cases per year, has reported more than 3,700 cases. Investigators have not yet identified the source of contamination.
On 1 July 2025, the CDC downgraded FoodNet, the active surveillance network it has run with the FDA, USDA and 10 state health departments since 1995. Tracking of Cyclospora, along with listeria, campylobacter, shigella, vibrio and yersinia, became optional at its sites. Only Salmonella and E. coli remained mandatory. The change arrived with budget cuts and no public announcement, and was reported almost two months later.
Why surveillance matters
Cyclospora is not transmitted from person to person; oocysts must mature in the environment for days before infecting someone. Every case traces back to contaminated food or water. The incubation period is about a week, so by the time a patient is tested, the contaminated produce has been consumed or shipped onward. Effective treatment exists for individual patients, but ending outbreaks requires identifying and removing the source from the food supply. According to Dr. Robert B Shpiner, a clinical professor of medicine at UCLA, "For cyclospora, surveillance is not the paperwork that accompanies the treatment. Surveillance is the treatment."
The downgrade's impact is evident: through early July, the CDC's national tally held at 145 cases. By 13 July, the confirmed figure had jumped to 1,645, with a single state reporting more illness than the entire country had officially registered. A count that lands after the food has been eaten can document an outbreak but cannot stop one.
Official rationale and broader context
The CDC stated that funding has not kept pace with resources required for all eight pathogens, that remaining pathogens are trackable through other systems, and that a narrower mandate allows focus on core work. However, the other systems are slower and passive, as demonstrated during this fast-moving outbreak.
The FoodNet downgrade is not an isolated act. More than 3,000 public health workers have left the CDC through firings, forced retirements and attrition, roughly a quarter of its workforce by the end of last year, according to KFF Health News. Much of the CDC's work involves pushing money and expertise to state and local departments that conduct interviews and food tracebacks. The Trump administration has described the department as bloated and promised to close wasteful and duplicative programs. The redundancy eliminated here was the capacity to notice.
Lessons from history
Dr. Shpiner, who began practicing intensive care medicine in Los Angeles in 1981 during the early AIDS epidemic, draws an institutional lesson: "What a health system does not measure can spread in plain sight, and by the time the measurement catches up, the argument is no longer about prevention." He recommends restoring Cyclospora to mandatory active surveillance at FoodNet sites, publishing national counts weekly through summer, and rebuilding state and local teams. This capacity is modest in cost compared to the illness and hospital admissions it prevents.
Surveillance is not clerical overhead. It is the promise a country makes to its citizens that it will notice when they begin to get sick. As Dr. Shpiner warns, "We are withdrawing that promise quietly, one pathogen at a time, and we are practicing on a parasite that rarely kills. The organism that tests this system next may be less forgiving."
