Catered Wedding Norovirus Outbreak and Permit Suspension
At a wedding reception for 210 guests, 78 people develop vomiting and diarrhea 24–48 hours after eating a buffet prepared by a licensed caterer. The menu included chilled shrimp salad, cut fruit, roast beef, and a whipped cream cake. The caterer's two food workers reported diarrhea during prep but wore gloves; one continued working the event. Inspectors find a handwashing sink blocked by stacked trays and a refrigerator holding shrimp salad at 12°C. The local lab detects norovirus GII in two guest stool specimens but has not tested food. The caterer agrees to discard remaining food but refuses to stop operating. The county may suspend a food permit when an imminent health hazard exists. The wedding party wants a shutdown and public notice; the caterer says the illness could be from a guest who brought a child to the buffet.
1. Assess the evidence for norovirus and for the caterer as the source, including the attack rate and alternative explanations.
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Attack rate: 78 ÷ 210 × 100 = 37%, which is high for a point-source foodborne outbreak and consistent with norovirus.
Supporting evidence
- Incubation of 24–48 hours and vomiting plus diarrhea fit norovirus.
- Two guest stool specimens are positive for norovirus GII.
- A food worker had diarrhea during preparation and another worked while ill; gloves do not replace handwashing and can contaminate surfaces.
- The blocked handwashing sink and shrimp salad held at 12°C create opportunities for contamination and amplification.
Limits
The food was not tested, and the guest-child explanation is possible but weak: a single child would not easily explain 78 illnesses unless the child contaminated a widely served item. The caterer is not proven as the source without a cohort analysis showing higher attack rates among people who ate specific foods, especially shrimp salad, and without excluding other exposures.
Conclusion: Norovirus is the likely agent and the caterer is the leading source, but the investigation should collect food-specific attack rates, worker stool samples, and invoices to confirm. The evidence is already sufficient for immediate control.
2. Decide whether to suspend the food permit immediately, and specify the findings and corrective actions required before reopening.
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Decision: suspend the permit immediately.
The county has an imminent health hazard: a highly infectious food worker, a blocked handwashing sink, temperature abuse of a ready-to-eat shrimp salad, and an outbreak with a 37% attack rate. Voluntary food discard does not address ongoing operations. Suspension should be in writing, state the factual findings and legal authority, and give appeal rights.
Corrective actions before reopening
- Exclude the ill worker and any other symptomatic staff until at least 48 hours after symptoms resolve.
- Discard all implicated ready-to-eat foods and clean and sanitize the facility with an EPA-registered product effective against norovirus.
- Unblock and restock the handwashing sink; verify hot water, soap, and paper towels.
- Repair or adjust refrigeration so cold holding is at or below 5°C.
- Retrain staff on ill-worker reporting, handwashing, and bare-hand contact.
- Submit a written cleaning and illness policy, then pass a reinspection.
Reasoning: The order is proportionate to a documented ongoing hazard and includes a clear path to reopening.
3. Draft a public health notice that names the caterer but avoids implying individual guilt.
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Public health notice: gastrointestinal illness linked to a catered event
The county health department is investigating an outbreak of vomiting and diarrhea among people who attended a wedding reception on [date] catered by [caterer]. As of [date], 78 of 210 guests reported illness. Two guest specimens tested positive for norovirus. The investigation is ongoing, and the caterer's food permit has been suspended while corrective actions are completed.
Advice to guests: If you develop vomiting, diarrhea, or abdominal cramps, drink fluids and contact a healthcare provider if symptoms are severe or persistent. Stay home while ill and for at least 48 hours after symptoms resolve. Wash hands frequently and do not prepare food for others while ill.
What this notice does not mean: A positive guest specimen and an inspection finding do not establish that any individual worker or the caterer intentionally caused illness. The department is identifying the source and preventing further cases.
For questions, call [number]. Updates will be posted at [website].