'Sharp rise' in cyclosporiasis cases in UK linked to Mexico travel. Here's what to know
Health officials in the U.K. are reporting a "sharp rise" in cyclosporiasis cases among travelers returning from Mexico.
Between April 30 and July 15, 67 cases have been reported among some returning travelers in England, Wales and Scotland, according to data published last week from the U.K. Health Security Agency (UKHSA).
Comparatively, an annual average of 93 cases has been recorded between 2022 and 2025, UKHSA data shows.
It comes as cases of cyclosporiasis continue to spread across the United States with at least nine states identified as part of an outbreak. The outbreak has been linked to shredded iceberg lettuce served at some Taco Bell restaurants, supplied by Taylor Farms and sourced from central Mexico.
The multi-state outbreak has led to two deaths in Michigan, state health officials announced Monday. Deaths from cyclosporiasis are rare, officials say.
Taylor Farms issued a voluntary recall of all iceberg lettuce sourced from central Mexico.
John Brownstein, an epidemiologist, chief innovation officer at Boston Children's Hospital and an ABC News medical contributor, said cases in multiple countries linked to Mexico -- be it travel or sourced produce -- underscore the challenge of understanding the source of infections.
"It highlights a likely source at a country level, but we still don't fully appreciate where the contaminations have occurred: farms, water, processing or distribution," he said. "We still don't even know if it's one or several farms that are sharing a common source. There's been real challenges identifying specific products [and] environmental samples as positive."
Brownstein went on, "So it's not surprising that we see illness connected to supply chain, but also illness connected with people actually in the areas where the potential source of the outbreak took place."
The UKHSA said travel information is available for 51 out of the 67 cases, of which 48 reported travel to Mexico.
Among patients who traveled to Mexico, they reported staying at a variety of hotels in the Cancún and Riviera Maya regions and consuming a range of foods and beverages as part of all-inclusive packages, according to the UKHSA. Officials said investigations are ongoing.
Brownstein added that it's possible health officials are seeing more cases because more people are being tested due to increased awareness.
"We always have to remember when it comes to surveillance, awareness can drive identification of cases," he said. "Even here in the U.S., we're probably seeing increased testing [more] than we see normally. Now, this doesn't discount the fact that we have an outbreak, but ... those that come in with stomach or gastrointestinal issues back from travel, they'll be more prone to getting that testing."
In the U.S., cases of cyclosporiasis have topped 18,000 in 45 states, according to the latest data from the Centers for Disease Control and Prevention.
There are at least 6,707 laboratory-confirmed cases of cyclosporiasis, including 423 hospitalizations, the CDC data shows. The agency is also aware of at least 11,500 additional cases that have not yet been laboratory confirmed or require further investigation and analysis.
Brownstein said individuals shouldn't panic and don't need to avoid all leafy greens but rather they should keep up with updates from the CDC and Food and Drug Administration and avoid any recalled products.
