This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
[{'content': 'Best test to diagnose prodrome of Hepatitis A ? \nSelect and explain. \nA. HAV in blood, B. IgG anti-HAV, C. IgM anti-HAV, D. HAV in stool', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. is \'c\' i.e., IgM anti-HAV Lab diagnosis of HAV "Detection of IgM - specific anti-HAV in the blood of an acutely infected patient confirms the diagnosis of hepatitis A". IgM appears in acute phase, peaking about 2 weeks after elevation of liver enzymes and becomes undetectable within 3-6 months. ELISA is the method of choice for measuring antibodies. Diagnosis can also be established by detection of virus in the stool from about 2 weeks prior to the onset of jaundice up to 2 weeks after. "But these tests for detection of HAV, are not widely available or useful in practice".', 'role': 'assistant'}]