Which marker appears last during hepatitis A infection according to the described sequence?

Which marker appears last during hepatitis A infection according to the described sequence?

• A. Stool antigen
• B. IgM antibody
• C. IgG antibody
• D. IgA antibody

Answer: (C)

In hepatitis A infection, the immune response evolves from early viral shedding in stool to acute antibodies, then to lasting immunity. The first signal is the virus being present in stool, an early marker of infection. Shortly after, IgM anti-HAV rises, indicating an acute infection. Later, IgG anti-HAV appears and persists for life, providing long-term protection and signaling immunity from past infection or vaccination. Because IgG comes after the initial acute response and remains as the durable marker of immunity, it is the last marker to appear among these options. Stool antigen reflects early infection, and IgA is not the final durable indicator in this sequence.

In hepatitis A infection, the immune response evolves from early viral shedding in stool to acute antibodies, then to lasting immunity. The first signal is the virus being present in stool, an early marker of infection. Shortly after, IgM anti-HAV rises, indicating an acute infection. Later, IgG anti-HAV appears and persists for life, providing long-term protection and signaling immunity from past infection or vaccination. Because IgG comes after the initial acute response and remains as the durable marker of immunity, it is the last marker to appear among these options. Stool antigen reflects early infection, and IgA is not the final durable indicator in this sequence.