Public Health England is investigating an increase in Cyclospora infections for the fourth successive year. Up to early August, 57 cases had been reported in England, Scotland and Wales, of which 46 had travelled to Mexico.
Where information is known, people who were infected stayed at several different hotels in the Cancun and Riviera Maya region, mostly on an all-inclusive basis. Officials say that suggests the source is likely to be a foodstuff distributed to hotels in the area.
The outbreak is being monitored by Public Health England (PHE), Health Protection Scotland, Public Health Wales and the Public Health Agency in Northern Ireland.
Between 2005 and 2014, an average of 32 Cyclospora cases were reported in England and Wales each year. Foods commonly contaminated with the parasite are soft fruits such as raspberries and salad products such as coriander, basil, and lettuce.
Cyclospora infection, cyclosporiasis, causes watery diarrhea, nausea, loss of appetite and abdominal cramps, usually within two to 14 days after the ingestion of oocysts.
PHE said there may be substantial under reporting of cyclosporiasis cases, because not all patients are tested for Cyclospora and not all positives are reported by laboratories. The organisms can also be difficult to spot and recognize in unstained wet films or concentrates.
In 2015, Cyclospora cayetanensis was identified in 176 returned travelers from the Riviera Maya region of Mexico between June and September; there were 79 in the United Kingdom and 97 in Canada.
One year later a similar outbreak in the UK involved 443 cases between June and October, 359 of whom reported travel to Mexico, mostly to the Riviera Maya and Cancun regions. France reported six confirmed and three probable cases in July and August 2016 in travelers from Mexico.
In 2017, 78 cases were recorded in the UK, of which 37 travelled to Mexico. However, 14 cases had traveled to nine other overseas destinations and seven had no overseas travel.
Belgium noted four cases of cyclosporiasis in 2017, three of whom had a travel history to Mexico.
In an assessment last year, the European Centre for Disease Prevention and Control (ECDC) said risk from Cyclospora infection amongst travelers to Mexico was high due to the lack of confirmation of suspected vehicles and related control measures.
Cyclosporiasis is not a mandatory notifiable disease in most European countries. The ECDC recommended awareness of the infection be raised among travelers and travel agencies as well as clinical laboratories and healthcare professionals.
In the United States, there are two ongoing multistate outbreaks of cyclosporiasis.
One is from Fresh Express salad mix sold at McDonald’s restaurants. A total of 395 cases have been reported from 15 states including 16 hospitalizations.
The other is linked to Del Monte Fresh Produce vegetable trays where 237 laboratory-confirmed cases come from four states. The trays contain broccoli, cauliflower, carrots, and dill dip.
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