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An outbreak of Cryptosporidium parvum linked to pasteurised milk from a vending machine in England: a descriptive
Anya Gopfert1, Rachel M Chalmers2,3, Sarah Whittingham4
1Health Protection Team, UK Health Security Agency South West, Bristol, UK.
Abstract:
We describe the investigations and management of a Cryptosporidium parvum outbreak of linked to consumption of pasteurised milk from a vending machine. Multiple locus variable number of tandem repeats analysis was newly used, confirming that C. parvum detected in human cases was indistinguishable from that in a calf on the farm. This strengthened the evidence for milk from an on-farm vending machine as the source of the outbreak because of post-pasteurisation contamination. Bacteriological indicators of post-pasteurisation contamination persisted after the initial hygiene improvement notice. We propose that on-farm milk vending machines may represent an emerging public health risk.
Insights
A Cryptosporidium parvum outbreak linked to pasteurized milk from vending machines highlights a potential public health risk. Investigations confirmed post-pasteurization contamination as the source.
Area of Science:
- Foodborne illness epidemiology
- Microbial source tracking
- Public health risk assessment
Background:
- Cryptosporidium parvum outbreaks pose significant public health challenges.
- Pasteurized milk is generally considered safe, but contamination risks exist.
- On-farm milk vending machines offer direct consumer access but require stringent hygiene protocols.
Purpose of the Study:
- To investigate and manage a Cryptosporidium parvum outbreak linked to pasteurized milk from a vending machine.
- To identify the source and transmission route of the outbreak.
- To assess the public health implications of on-farm milk vending machines.
Main Methods:
- Epidemiological investigation of human cases.
- Microbiological analysis of milk and environmental samples.
- Multiple Locus Variable Number Tandem Repeats (MLVA) analysis for microbial source tracking.
Main Results:
- MLVA confirmed indistinguishable C. parvum strains in human cases and a farm calf.
- Evidence strongly implicated post-pasteurization contamination of milk from an on-farm vending machine.
- Bacteriological indicators of contamination persisted despite hygiene interventions.
Conclusions:
- On-farm milk vending machines can be a source of post-pasteurization contamination.
- Cryptosporidium parvum outbreaks linked to milk vending machines represent an emerging public health concern.
- Enhanced surveillance and hygiene practices are crucial for milk vending machine safety.
