Four Guests Vomiting Two Hours After a Church Lunch
A café served a set lunch to a church group of 40 on Sunday at 12:30 p.m. The menu was baked ham, chicken salad, rice pilaf, green salad, and rolls. Between 2:45 and 3:30 p.m., four of the 40 guests began vomiting; one also had stomach cramps. None of the four had diarrhea. A fifth guest reported diarrhea at 9:00 p.m. on Monday. All four who vomited ate the rice pilaf and the chicken salad; the fifth guest ate only the ham and rolls. Leftover chicken salad and rice are still in the walk-in. The owner wants to reheat both to 165°F and put them back on Monday's line, and wants to know whether to open at all.
1. Using the onset times and symptoms, what kind of hazard are you hunting for, and which menu items deserve the most scrutiny? Explain how the Monday case fits into the picture - or doesn't.
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Short onset plus vomiting means the toxin was already in the food. A person cannot grow enough bacteria in their gut to vomit 2¼ hours after eating. So look for organisms that produce toxin in the food before it is eaten:
- Staphylococcus aureus - a handler's hands, a cut or rash, or a sinus infection contaminating protein-rich food. The chicken salad (mixed by hand, creamy, often held cold in a big tub) and the ham are the classic vehicles.
- Bacillus cereus, emetic type - cooked rice held warm and then cooled slowly. This one fits the rice pilaf almost too well.
Rank the leads by how well the food explains the pattern, not by how nervous you are about it. The rice is the strongest lead because cooked rice is the textbook vehicle and because rice pilaf is the item most likely to sit in the danger zone. The chicken salad is a close second because it is a bare-hands food.
The Monday guest does not belong in this cluster. A 32-hour onset is far too slow for a pre-formed toxin and sits right in the window for a live infection (Salmonella, Norovirus, Campylobacter). Record it, interview that guest about what else they ate, and investigate it separately. Combining the two will send you chasing the wrong food.
Also compare attack rates by item: 4 of 40 is small, so confirm what the other 36 actually ate before concluding anything.
2. The owner's plan is to reheat the leftover chicken salad and rice to 165°F and serve them Monday. Is that safe? Give your decision and the reasoning.
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No. Reheating will not fix this food.
Staphylococcal enterotoxin and the emetic toxin of B. cereus (cereulide) are heat-stable. Boiling destroys the bacteria but not the toxin they have already produced. Reaching 165°F makes the food look properly cooked and changes nothing about the hazard.
Decision: hold the leftovers - do not serve and do not repurpose them into another dish. Notify the local health authority, and keep the food available in case they want to sample it. If they don't want it, discard it. Discard is the defensible call even without confirmation, because you do not need a confirmed link to stop serving a suspect food.
One more trap: do not quietly serve the ham instead on the theory that nobody got sick from it. A food that has been in the same kitchen during the same service is inside the investigation until the investigation says otherwise.
3. Name three checks you would make in the kitchen, and say what result would point to the rice versus the chicken salad and ham.
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1. The rice timeline. After cooking, was the pilaf held at 135°F or above, and when it was cooled, did it go from 135°F to 70°F within 2 hours and to 41°F within 6 hours total? If you find it sitting in a deep bus tub at room temperature, or a full hotel pan parked in the walk-in overnight, that points to B. cereus.
2. Hands on the chicken salad. Was it mixed, portioned, or plated with bare hands? Is there any handler with a cut, boil, rash, or infected fingernail on hands, wrists, or forearms, or someone who has been sneezing over the prep table? Any yes points to S. aureus. Cold holding at 41°F or below matters too - a salad tub left on the counter during service gives the organism hours to multiply and make toxin.
3. Who worked and how sick were they. Anyone on the schedule with vomiting, diarrhea, or a skin infection in the days before Sunday? Was the hand sink stocked and used?
What each result buys you: a clean rice record plus a handler with an uncovered hand wound points the investigation at the chicken salad; an unrefrigerated hotel pan of rice plus clean hands points at the pilaf. If both checks come back clean, look again at the ham - sliced meats handled after cooking are a well-documented S. aureus vehicle.