Cilantro grown in the Puebla, Mexico, area is suspected as the cause of at least some of the cases in a summer outbreak of Cyclospora infections in Texas, which now appears to be over, according to state and federal officials.
At least 18 other states are tracking cyclosporiasis cases, but there is no indication that any of their cases are linked to cilantro from Mexico, the Centers for Disease Control and Prevention (CDC) said in an update yesterday.
Texas: 126 cases
The Texas Department of State Health Services (DSHS) said yesterday that the state's outbreak seems to be over after 126 cases in which patients fell ill after May 1 and had no history of international travel in the 2 weeks before onset. The state has had a total of 166 Cyclospora cases this year.
"The number of new illnesses being reported has returned to background levels, and the investigation has linked the cases in four restaurant clusters to cilantro imported from Puebla, Mexico," the DSHS said in a press release.
The DSHS and local health departments investigated four restaurant clusters in North Texas that included a total of 21 people who got ill, the agency said. All 21 reported eating a food item from the restaurant containing cilantro within 2 weeks before they became ill.
A preliminary trace-back investigation by the US Food and Drug Administration (FDA) and the DSHS identified Puebla, Mexico, as the source of the cilantro that was served in all four restaurants, the state agency said.
No cilantro with Cyclospora contamination has been found, but there is enough evidence to establish a strong epidemiologic link between the illnesses and the cilantro, the DSHS said. It noted that the state of Puebla was also identified as the source of fresh cilantro linked to a cyclosporiasis outbreak in 2013.
US 2014 total: 304 cases
On the national front, the CDC said yesterday that 304 cyclosporiasis cases have been reported this year through Aug 26. Of those cases, 207 patients from 19 states had no history of international travel in the fortnight before they got sick. Texas accounted for 133 (64%) of the 207 cases, the agency said.
Among 183 persons with available information, 7 (4%) reported being hospitalized, but no one has died, the CDC said. Most of the patients (85%) got sick in June or July.
Two weeks ago the CDC had put the total count of cyclosporiasis cases at 283—21 fewer than in yesterday's update. At that point the agency had not sorted out how many of the patients had recently traveled abroad.
Noting Texas's findings about cilantro, the CDC said, "To date, there is no evidence to suggest that any illnesses outside of Texas are linked to cilantro from Puebla, Mexico."
Increased FDA sampling
Yesterday the FDA announced it was increasing surveillance sampling of cilantro imported from Puebla and was working with Mexican authorities to determine if there is a common farm or growing area there that could have provided the fresh cilantro linked to the outbreak.
As is true this year, Texas was the hardest-hit state in last summer's multistate Cyclospora outbreak, which involved at least 631 people in 25 states and New York City. Past foodborne Cyclospora outbreaks have been linked to many kinds of imported fresh produce, including raspberries, basil, snow peas, and mesclun.
Aug 28 Texas DSHS statement
Aug 28 CDC update
Aug 28 FDA statement
Related Aug 14 CIDRAP News item