Duration of Dengue IgG Antibodies
Dengue IgG antibodies persist for months to years after infection, providing long-lasting immunity. 1
Timeline of Antibody Development
- IgG antibodies develop around day 5-7 after symptom onset in primary dengue infections, and appear even earlier in secondary infections 1
- In contrast, IgM antibodies typically appear 3-5 days after symptom onset 1
Long-Term Persistence of IgG
- IgG antibodies remain detectable for years following dengue infection, making them useful markers of past infection rather than acute disease 1
- Research demonstrates that 96.61% of symptomatic dengue patients still had detectable IgG antibodies three years after their initial infection 2
- The persistence of IgG is significantly higher in symptomatic patients compared to asymptomatic individuals (96.61% vs 27.08% at 3 years), with an odds ratio of 76.731 2
Clinical Implications
- IgG testing is not useful for diagnosing acute dengue infection because these antibodies persist long-term and cannot distinguish between current and past infections 1
- For acute diagnosis within 7 days of symptom onset, nucleic acid amplification tests (NAATs) and NS1 antigen detection are preferred 1
- For specimens collected >7 days after symptom onset, IgM antibody testing becomes the preferred diagnostic method 1
Important Caveats
- IgG antibodies can cross-react with other flaviviruses, potentially causing false-positive results 1
- In areas with multiple circulating flaviviruses, confirmatory plaque reduction neutralization tests (PRNTs) may be required for definitive diagnosis 1
- The long-term presence of IgG antibodies may play a role in antibody-dependent enhancement (ADE) during secondary dengue infections with different serotypes 2