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. 2015 May 27;10(5):e0125955.
doi: 10.1371/journal.pone.0125955. eCollection 2015.

An Outbreak of Cryptosporidium parvum across England & Scotland Associated with Consumption of Fresh Pre-Cut Salad Leaves, May 2012

Caoimhe McKerr  1 , Goutam K Adak  2 , Gordon Nichols  3 , Russell Gorton  4 , Rachel M Chalmers  5 , George Kafatos  6 , Paul Cosford  7 , Andre Charlett  6 , Mark Reacher  4 , Kevin G Pollock  8 , Claire L Alexander  8 , Stephen Morton  9
Affiliations

An Outbreak of Cryptosporidium parvum across England & Scotland Associated with Consumption of Fresh Pre-Cut Salad Leaves, May 2012

Caoimhe McKerr et al. PLoS One. .

Abstract

Background: We report a widespread foodborne outbreak of Cryptosporidium parvum in England and Scotland in May 2012. Cases were more common in female adults, and had no history of foreign travel. Over 300 excess cases were identified during the period of the outbreak. Speciation and microbiological typing revealed the outbreak strain to be C. parvum gp60 subtype IIaA15G2R1.

Methods: Hypothesis generation questionnaires were administered and an unmatched case control study was undertaken to test the hypotheses raised. Cases and controls were interviewed by telephone. Controls were selected using sequential digit dialling. Information was gathered on demographics, foods consumed and retailers where foods were purchased.

Results: Seventy-four laboratory confirmed cases and 74 controls were included in analyses. Infection was found to be strongly associated with the consumption of pre-cut mixed salad leaves sold by a single retailer. This is the largest documented outbreak of cryptosporidiosis attributed to a food vehicle.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. Cumulative count of cases of Cryptosporidium sp reported to national surveillance, weeks 1–25 inclusive, England & Wales, 2005–2012.
Fig 2
Fig 2. Cumulative count of cases of Cryptosporidium sp reported to national surveillance, weeks 1–25 inclusive, Scotland, 2005–2012.
Fig 3
Fig 3. Count of cases of Cryptosporidium sp reported to national surveillance by date of onset of illness, May 2012, England regions and Scotland.
See this image and copyright information in PMC

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