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    Infection Testing (Serology vs PCR)

    Different test types answer different questions. I help you avoid “positive = active” traps.

    • Antibodies (IgM/IgG/IgA): immune “memory” with timing rules
    • IgM: early responder (timing varies by illness)
    • IgG: longer-term memory (can persist for years)
    • IgA: mucous membrane defender (gut/respiratory)
    • PCR: detects genetic material—sensitive, but timing/sample quality matter
    • PRISM warning: positive ≠ active disease; negative ≠ none
    Good to know
    • I explain patterns and questions—not conclusions
    • PCR/serology should be read with symptoms and other tests

    PRISM is for learning, not diagnosing. It explains what tests measure and how clinicians reason — it never tells you what to conclude, and it doesn't replace your doctor.