title: Dengue virus infections and maternal antibody decay in a prospective birth cohort study of Vietnamese infants.
abstract: Dengue hemorrhagic fever can occur in primary dengue virus (DENV) infection of infants. The decay of maternally derived DENV immunoglobulin (Ig) G and the incidence of DENV infection were determined in a prospectively studied cohort of 1244 Vietnamese infants. Higher concentrations of total IgG and DENV-reactive IgG were found in cord plasma relative to maternal plasma. Maternally derived DENV-neutralizing and E protein-reactive IgG titers declined to below measurable levels in >90% of infants by 6 months of age. In contrast, IgG reactive with whole DENV virions persisted until 12 months of age in 20% of infants. Serological surveillance identified 10 infants with asymptomatic DENV infection for an incidence of 1.7 cases per 100 person-years. DENV-neutralizing antibodies remained measurable for > or = 1 year after infection. These results suggest that whereas DENV infection in infants is frequently subclinical, there is a window between 4 and 12 months of age where virion-binding but nonneutralizing IgG could facilitate antibody-dependent enhancement.
authors.affiliation: Oxford University Clinical Research Unit, Hong Vuong Hospital, Ho Chi Minh City, Vietnam.
authors.forename: Tran Nguyen Bich
authors.initials: TN
authors.lastname: Chau
authors.forename: Nguyen Trong
authors.initials: NT
authors.lastname: Hieu
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Anders
authors.forename: Marcel
authors.initials: M
authors.lastname: Wolbers
authors.forename: Le Bich
authors.initials: le B
authors.lastname: Lien
authors.forename: Lu Thi Minh
authors.initials: LT
authors.lastname: Hieu
authors.forename: Tran Tinh
authors.initials: TT
authors.lastname: Hien
authors.forename: Nguyen Thanh
authors.initials: NT
authors.lastname: Hung
authors.forename: Jeremy
authors.initials: J
authors.lastname: Farrar
authors.forename: Stephen
authors.initials: S
authors.lastname: Whitehead
authors.forename: Cameron P
authors.initials: CP
authors.lastname: Simmons
mesh_terms: D000367:Age Factors; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood*; D015331:Cohort Studies; D003716:Dengue Virus / Q000276:immunology*; D005260:Female; D006801:Humans; D007112:Immunity, Maternally-Acquired; D007074:Immunoglobulin G / Q000097:blood*; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D019595:Severe Dengue / Q000453:epidemiology*; D014744:Vietnam
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D007074:Immunoglobulin G