What are the differences between hepatitis E IgM and IgG?
Dec 03, 2025
Source: Cainiu Health
Dr. Huang Yuhong
Introduction
HEV IgM and IgG antibodies generally differ in terms of onset time, duration, antibody concentration, clinical significance, and infectivity. IgM antibodies are the earliest specific antibodies to appear after hepatitis E virus infection, typically detectable within 2 to 4 weeks after infection, indicating the acute phase of infection. IgG antibodies appear relatively later, usually during the middle-to-late stages of infection or during the recovery phase.
HEV IgM and IgG antibodies generally differ in terms of time of appearance, duration, antibody concentration, clinical significance, and infectivity. The specific analysis is as follows:
1. Time of appearance: IgM antibodies are the earliest specific antibodies to appear after hepatitis E virus (HEV) infection, typically detectable within 2 to 4 weeks after infection, indicating the acute phase of infection. IgG antibodies appear relatively later, usually during the mid-to-late stages of infection or during recovery.
2. Duration: IgM antibodies are short-lived, generally lasting for about 2 to 3 weeks before gradually disappearing. IgG antibodies can persist in the body for a longer period, sometimes for several months or even years.
3. Antibody concentration: During the early stage of infection, IgM antibody levels are high but gradually decline as the condition improves. IgG antibody levels remain relatively stable and may persist at detectable levels even after recovery.
4. Clinical significance: A positive IgM test indicates recent HEV infection and has value for early diagnosis. A positive IgG test suggests past infection or recovery phase and cannot alone determine the timing of infection.
5. Infectivity: A positive IgM result may indicate active viral replication, meaning the patient is infectious. A positive IgG result usually indicates that the acute phase has passed, with reduced or no remaining infectivity.
Interpretation of hepatitis E antibody tests should be based on a comprehensive evaluation including clinical symptoms and epidemiological history. If symptoms such as fatigue or jaundice occur, or if infection is suspected, medical attention should be sought immediately for serological testing and liver function assessment.
