UK says Cyclospora outbreak over as US continues investigation

Cyclosporiasis in UK travellers to Mexico has sickened 132 people.

A total of 44 cases were confirmed by a reference laboratory and 88 are probable cases.

Ill people are in England, Scotland, Wales, Isle of Man and Jersey.

Public Health England (PHE) said it was not possible to identify the vehicle of infection but it was likely a food or drink item.

Strong link to Mexico​

Cases began to increase from the beginning of June with the majority in June and July (92) compared to 203 in the same period in 2016.

Six cases were reported earlier in 2017 (two in January, one in March and three in May).

Of 132 cases, travel history is known for 109 of them. Of these, 84 reported travel to Mexico, 18 to 14 other destinations (including three to Dominican Republic) and seven did not travel outside the UK in the 14 days prior to onset of symptoms.

Of the 77 cases that travelled to Mexico with a known onset date the earliest date was 19 May and the most recent date was 18 August.

The median age for these cases was 42 years (range 16-77 years); 53% were female and 47% male.

Of the cases that travelled to Mexico, 74 had information about region or hotel they stayed at. Of these, all but one stayed in the Riviera Maya and Cancun region on the Caribbean coast of the Yucatán peninsula, north eastern Mexico.

Cases stayed at 27 different hotels, with 37 having stayed at one of three hotels and 37 cases stayed at 24 other hotels.

Food and drink exposures were available for 50 cases that travelled to Mexico.

More than two-thirds of cases consumed bottled water, mixed salad leaves, orange juice, tomatoes, mint in drinks, ice in drinks, lettuce and onions.

“It is likely that that the vehicle of infection was a food or drink item that is seasonally distributed to hotels in Riviera Maya given that cases have occurred during the UK summer months in 2015, 2016 and 2017 and travel to Mexico from the UK occurs year round,”​ said PHE.

US and Canada outbreaks​

The US Centers for Disease Control and Prevention (CDC) said it has been notified of 1,065 laboratory-confirmed cases of cyclosporiasis in people who became ill in 2017 from 40 states.

At least 597 of these did not report international travel and became ill on or after May.

The agency said no specific vehicle of interest has been identified.

Previous outbreaks have been linked to imported fresh produce (e.g., basil, cilantro, mesclun lettuce, raspberries or snow peas).

The Public Health Agency of Canada (PHAC) is investigating locally acquired Cyclospora infections in three provinces.

A total of 157 cases have been reported in British Columbia (17), Ontario (136), Quebec (three) and Nova Scotia (one) between May and August of this year.

The majority of cases (52%) are female with an average age of 48 years.