Answer:
This person most likely has been exposed to a(n) superantigen
Step-by-step explanation:
Some bacteria and viruses are producers of superantigens, proteins that stimulate a large proportion of T lymphocytes when they bind to the TCR and MHC-II, putting them in contact with each other for much longer than normal creating a more intense immune response, like the one observed in the example given. Staphylococcal enterotoxin A (SEA) and toxic shock syndrome toxin (TSST) are examples of these superantigens.
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