Measles antibody titers in early infancy.
OBJECTIVE
To determine the prevalence of measles seronegativity among infants younger than 6 months and to ascertain their serologic response to measles vaccine.


METHODS
Cross-sectional measles antibody survey during the 1989 measles epidemic in Chicago, Ill.


METHODS
Inner-city perinatal center.


METHODS
Two hundred three infants younger than 6 months who had been admitted to the neonatal intensive care unit at birth; 130 (64%) of these infants were premature. Transplacental antibody transfer was evaluated in a subset of 89 mother-newborn pairs.


METHODS
Administration of measles monovalent vaccine to seronegative infants.


RESULTS
Measles IgG antibody was measured using indirect fluorescent assay. At birth, 19 (38%) of 50 neonates born at less than 37 weeks' gestation had antibody titers that were twofold to fourfold lower than those of their mothers compared with three (8%) of 39 neonates born at more than 37 weeks' gestation (P < .01). Of the 203 study infants, fewer than 4% were seronegative at birth, while 74% of these infants aged 4 to 5 months were seronegative. Univariate logistic regression analysis indicated that the independent variables related to seronegativity were as follows: gestational age at birth (P = .007), chronological age (P < .001), history of having received three or more packed red blood cell transfusions (P < .001), and maternal age at delivery (P = .001). Multiple logistic regression analysis confirmed the association of seronegativity with chronological age (P < .001), gestational age (P < .02) and maternal age at delivery (P < .001). Seroconversion following administration of the measles vaccine was documented in 11 (79%) of 14 infants.


CONCLUSIONS
A significant proportion of 4- to 5-month-old infants who had been admitted to the neonatal intensive care unit at birth lack measurable measles antibody; this population should be taken into account when strategies to control measles are considered.
Kamat
M
M
Department of Pediatrics, Hektoen Institute for Medical Research, Cook County Children's Hospital, Chicago.
Pyati
S
S
Pildes
R S
RS
Jacobs
N
N
Luayon
M
M
Muldoon
R
R
Levy
P S
PS
D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D005260:Female; D006801:Humans; D007112:Immunity, Maternally-Acquired; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D008457:Measles / Q000276:immunology*; D008458:Measles Vaccine / Q000276:immunology*; D011446:Prospective Studies
D000914:Antibodies, Viral; D007074:Immunoglobulin G; D008458:Measles Vaccine