Loss of maternal measles antibody in black South African infants in the first year of life--implications for age of vaccination.
In order to investigate the feasibility of measles vaccination before the age of 9 months the duration of passive immunity against measles was estimated by conducting a longitudinal study of measles antibody levels in 20 black neonates delivered at term. Measles serum antibody (IgG) was measured by enzyme-linked immunosorbent assay in the mother at childbirth and on consecutive samples taken from the infants from birth until 9 months of age. Protective measles antibody level was defined as greater than 200 mIU. Unprotective levels were found in 88% (95% confidence interval (CI) 81-99%) of 6-month-old infants, while at 9 months all were susceptible. The mean antibody level was 192 mIU (CI 104-348%) at 4 months; 34 mIU (CI 15-73%) at 6 months and 13 mIU (CI 6-24%) at 9 months of age. Our data support the recent World Health Organisation recommendation to immunise children in developing countries at 6 months with the 'high titre' Edmonston-Zagreb measles vaccine, since most infants in our study had lost passive immunity against measles by this age.
Kiepiela
P
P
Department of Paediatrics and Child Health, University of Natal, Durban.
Coovadia
H M
HM
Loening
W E
WE
Coward
P
P
Abdool Karim
S S
SS
D000367:Age Factors; D000914:Antibodies, Viral / Q000032:analysis*; D044383:Black People; D005260:Female; D006801:Humans; D007112:Immunity, Maternally-Acquired; D007115:Immunization Schedule; D007074:Immunoglobulin G / Q000276:immunology; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008457:Measles / Q000276:immunology*; D013019:South Africa
D000914:Antibodies, Viral; D007074:Immunoglobulin G