The United States is grappling with what experts are calling the largest cyclosporiasis outbreak in its history, with Michigan alone reporting more than 5,000 cases — a staggering figure in a state that typically sees fewer than 50 cases in an entire year. The surge comes as federal and state public health agencies, hollowed out by billions in funding cuts, struggle to contain the parasitic disease before it spreads further.
An Outbreak Without Precedent
When Michigan health officials first detected cyclosporiasis cases in late June, they launched an emergency response that has not let up since. Notifications went out to federal agencies and the public ahead of the July holiday weekend, warning home cooks and commercial kitchens about the dangers of potentially contaminated produce. Teams worked straight through the break and have not taken a single day off since.
The numbers tell a stark story. By Friday, Michigan had recorded more than 5,000 confirmed cases — a jump of 1,300 from just three days earlier — alongside 102 hospitalisations. The parasite, which triggers weeks of explosive diarrhoea and vomiting, has also surfaced across five states: Indiana, Kentucky, Ohio, and West Virginia, all linked by the CDC. But the true footprint is almost certainly wider, because cyclosporiasis can take weeks to manifest, meaning officials cannot yet determine whether their warnings have stemmed the tide.
“If we focus only on Michigan’s numbers, this is almost certainly the biggest outbreak of cyclosporiasis in US history,” said Natasha Bagdasarian, Michigan’s chief medical executive.
A Workforce Decimated
The crisis is unfolding against a backdrop of severe institutional erosion. In March 2025, the Trump administration slashed $12bn in public health funding, stripping away laboratory capacity, disease monitoring infrastructure, and outbreak investigation resources. Half of US states joined a lawsuit to reclaim those funds, but the states that did not join the legal challenge never received the money — and disbursement delays triggered layoffs, furloughs, and widespread uncertainty across the sector.
Michigan’s experience is emblematic. The state lost an entire regional laboratory and 23 employees from its bureau of infectious diseases. Local health departments shed a further 123 staff due to the federal funding squeeze. At the federal level, the CDC has shed roughly one-third of its workforce, and most permanent leadership positions now sit vacant.
“If you lose one player from a football squad, you might not trace every goal back to that absence, but you will feel the impact,” said Susan Kansagra, chief medical officer at the Association of State and Territorial Health Officials. “It catches up with you over time, and that is precisely what we are witnessing now — multiple public health threats landing on a workforce and a funding climate that are already stretched to breaking point.”
Surveillance Gaps and a Tepid Federal Response
Communication between state and federal agencies has faltered. Bagdasarian noted that during previous outbreaks, the CDC provided additional assistance and coordination — support that has been conspicuously absent this time. The CDC issued a health advisory to medical providers on a Tuesday, some two weeks after the first warning signs had emerged. Robert F Kennedy Jr, the secretary of the Department of Health and Human Services, made his first public remarks about the outbreak on a Friday, appearing on a Tampa-based podcast where he downplayed the severity by noting that “there are cyclospora outbreaks every summer” without clarifying that current case numbers are dramatically elevated.
The surveillance picture has been further complicated by policy changes. In 2025, the administration designated cyclospora and several other pathogens as optional for reporting to FoodNet, the national foodborne-illness tracking system. Melanie Firestone, assistant professor at the University of Minnesota School of Public Health, warned that these reductions will make it increasingly difficult to identify trends and risk factors in foodborne illness over time. However, she stressed that FoodNet is not the primary mechanism through which outbreaks are detected in the United States.
“FoodNet gets a lot of attention, but the real issue is how much funding state and local health departments receive to do this work,” Firestone said. “The CDC plays a vital coordinating role in multi-state outbreaks and aggregating data. Any funding constraints that limit their capacity are a contributing factor.”
The Investigation and the Cost of Detection
Michigan’s public health staff have devoted more than 1,000 hours to patient interviews, layered on top of the coordination burden of the response itself. Only four specialists in gastrointestinal illness are assigned to the state’s team, with dozens more pulled into the cyclospora effort — and away from other critical programmes.
“We have to prioritise and make the best of what we have,” Bagdasarian said. “There is only so much bandwidth. Pull too many people from one area and you begin to see consequences elsewhere.”
Those consequences are already visible. Health departments are simultaneously screening between 100 and 150 travellers arriving in the United States each day, monitoring outbreaks of measles, mumps, and pertussis, and contending with summer heatwaves and wildfire smoke from Canada that is degrading air quality.
The laboratory effort itself is running out of money. Michigan has approximately 2,000 samples that have been sequenced or are awaiting sequencing, but at $122 per test, the lab has already blown through its entire cyclospora budget. Meanwhile, diagnosis remains a barrier for patients. Tests cost several hundred dollars, insurance may not cover the full expense, and high copayments are deterring even insured individuals from seeking testing. Those who have lost Medicaid coverage under federal cuts face even steeper obstacles.
“There are people who are uninsured or underinsured because of these federal cuts to Medicaid,” Bagdasarian said. “More people are falling off coverage, which means it is going to be harder for us to know how many cases are actually out there.”
The Source and the Spread
Investigators have pointed to shredded iceberg lettuce from a supplier in Mexico as the probable source, with Taco Bell named as an affected restaurant chain. But Bagdasarian cautioned that the outbreak likely extends far beyond a single brand.
“There is no single place that has jumped out at us,” she said. “The question is where contamination occurred upstream — and many of these producers supply not only restaurants and fast-food chains but also grocery stores.”
Taylor Farms, a California-based company with operations in Mexico, has previously been linked to a 2013 cyclospora outbreak at Olive Garden and Red Lobster, as well as an E. coli outbreak tied to slivered onions at McDonald’s in October 2024. The company has not publicly commented on the current investigation.
Why it Matters
This outbreak lays bare a dangerous feedback loop: when public health infrastructure is defunded, the systems that detect, track, and contain infectious diseases degrade precisely when they are needed most. The United States is not facing a single isolated threat — it is confronting cyclosporiasis alongside measles, mumps, pertussis, and environmental health emergencies, all while its frontline workforce has been halved and its surveillance networks have been deliberately weakened. The $12bn in cuts made in 2025 did not merely reduce budgets; they removed the capacity to identify outbreaks early, respond swiftly, and protect the most vulnerable communities. As this parasitic outbreak spirals across multiple states, the question is no longer whether these cuts were affordable — it is whether the country can afford what comes next.
