Seroprevalence of dengue virus antibody in Korea

Purpose: The number of dengue fever cases is rising due to increasing overseas travel. Vaccination makes severe dengue fever in seronegative individuals after vaccination when they exposure to wild-type dengue virus. We investigated the seroepidemiology of the dengue virus for monitoring of Korean dengue virus immunity and establishing the prevention of dengue infection. Methods: The study was based on 446 residual sera collected from 98 infants (2 months to 1 year old), 152 adolescents (13 to 19 years old), 90 adults (20 to 50 years old), and 106 elderly participants (more than 65 years old) for other studies. Antibody levels for dengue virus immunoglobulin G (IgG) in each age group were measured using an enzyme-linked immunosorbent assay (ELISA). For each dengue virus IgG positive or equivocal result, an IgG ELISA was performed for Japanese encephalitis virus. Results: Of the 446 serum samples, only 1 (0.2%) adolescent had a positive result from the dengue IgG antibody test. In the dengue virus IgG antibody test, 14 (3.1%) samples showed equivocal results (10 adolescents and 4 elderly). In the 1 positive case of dengue virus IgG, the Japanese encephalitis IgG test was also positive. In the 14 equivocal cases of dengue virus IgG, there were 6 positive, 3 equivocal, and 5 negative of Japanese encephalitis IgG. Conclusions: The seroprevalence rate of dengue virus was very low in Koreans. This study provides important data for establishing the policy for preventive measures of dengue fever. It will be necessary to continuously monitor for dengue virus immunity.