A guest experienced a reversal of hot and cold sensations after eating seafood. What most likely caused the illness?

The experience of a reversal of hot and cold sensations after eating seafood is a significant indicator of a particular type of illness caused by toxins, specifically those produced by certain species of fish. This effect is often associated with the consumption of seafood that contains neurotoxins, such as those from the dinoflagellate organism that can contaminate shellfish, leading to conditions like ciguatera poisoning.

Neurotoxins directly affect the nervous system, resulting in unusual sensory experiences such as the reversal of hot and cold sensations. This is a classic symptom associated with toxin-related foodborne illnesses, particularly when the source is seafood. When these toxins enter the body, they disrupt normal nerve function, leading to the neurological symptoms described.

In contrast, bacterial infections typically manifest with gastrointestinal symptoms like diarrhea, vomiting, and fever, while allergens can provoke immune responses with symptoms like itching, hives, or respiratory issues. Pesticide poisoning may present with a variety of symptoms including headaches, nausea, and other systemic effects, but wouldn’t specifically cause the peculiar sensation reversal noted in this scenario. Thus, toxins are clearly the most probable cause of the symptoms described.