During a visit to Busan, I ate clams and pork belly together, which led to abdominal pain and diarrhea. I visited Kim Du-hee's Family Medicine Clinic for a consultation. I was surprised when asked if I had recently consumed shellfish or oysters. I was diagnosed with norovirus and prescribed medication. After taking the medication for about two days, I recovered completely. After hearing the director's detailed explanation, I learned once again that norovirus does not die when boiled or fried in shellfish and oysters, even in winter. I was grateful that I was the only one experiencing these symptoms, even though I had eaten with my family. I am deeply grateful for the kind and detailed explanation and the dedicated work of the nurses.