Dengue virus infections in the first 2 years of life and the kinetics of transplacentally transferred dengue neutralizing antibodies in thai children.
BACKGROUND
Understanding dengue virus infection in children and the kinetics of maternal dengue neutralizing antibodies is essential for effective dengue immunization of children in endemic areas.


METHODS
Serum samples from 219 mother-child pairs and 140 children at 3, 6, 9, 12, 18, and 24 months of age from Bangkok, Thailand, were tested for serotype-specific dengue antibodies. Febrile episodes in the children were recorded.


RESULTS
Antibodies were found in 97% of cord serum samples and disappeared in 27%, 80%, and 95% of the children by the age of 6, 9, and 12 months, respectively. Geometric mean titers (GMTs) of the antibodies to 4 dengue serotypes decreased to 5.4-15.5 in 6-month-old infants. Eleven of 12 children acquired dengue virus infection at 6 months of age and beyond; 1 had the infection at 3 months of age. Two exhibited undifferentiated febrile illnesses, and 10 had subclinical infections.


CONCLUSIONS
Evidence of dengue virus infection and very low GMTs against all dengue serotypes in children at 6 months of age and beyond was demonstrated. There was no evidence that maternal antibodies were harmful to infants. Dengue virus infection rates increase from 12 months of age onward. These data provide information for supporting the optimal age at vaccination.
Pengsaa
Krisana
K
Department of Tropical Pediatrics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. tmkps@mahidol.ac.th
Luxemburger
Christine
C
Sabchareon
Arunee
A
Limkittikul
Kriengsak
K
Yoksan
Sutee
S
Chambonneau
Laurent
L
Chaovarind
Udom
U
Sirivichayakul
Chukiat
C
Lapphra
Keswadee
K
Chanthavanich
Pornthep
P
Lang
Jean
J
D000914:Antibodies, Viral / Q000097:blood*; D002675:Child, Preschool; D003715:Dengue / Q000276:immunology* / Q000517:prevention & control*; D003716:Dengue Virus / Q000276:immunology*; D019353:Endemic Diseases; D004797:Enzyme-Linked Immunosorbent Assay; D005312:Fetal Blood / Q000276:immunology; D005335:Fever of Unknown Origin; D006801:Humans; D007112:Immunity, Maternally-Acquired; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007223:Infant; D007700:Kinetics; D009035:Mothers; D009500:Neutralization Tests; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D013785:Thailand
D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007075:Immunoglobulin M