Immunologic response of extremely premature infants to tetanus, Haemophilus influenzae, and polio immunizations.
OBJECTIVE
To determine whether extremely premature infants have immunologic responses to tetanus toxoid, Haemophilus influenzae type b polysaccharide and polio vaccines similar to those of full-term infants.


METHODS
Sixteen extremely premature (< 29 weeks, < 1000 g at birth) infants received separate diphtheria-tetanus-pertussis and H influenzae type b oligosaccharide-CRM197-conjugated (HbOC) vaccines at 2, 4 and 6 months of chronologic age, enhanced potency inactivated polio vaccine at 2 months, and oral polio vaccine at 4 months. Serum was obtained for anti-tetanus toxoid (TT), anti-Haemophilus b polysaccharide (HbPs) and polio neutralizing antibody assays before the 2-month vaccination and 4 to 6 weeks after the 6-month vaccination. Comparison sera were obtained from full-term infants immunized with the same lots of diphtheria-tetanus-pertussis (n = 46) and HbOC (n = 66) vaccines or the same sequence of polio vaccines (n = 10).


RESULTS
Preterm and full-term infants had similar geometric mean titers of anti-TT antibodies, anti-HbPs antibodies, and neutralizing antibodies to polio serotypes 1, 2, and 3 after the completion of the primary series of vaccines. After vaccination, similar proportions of preterm and full-term infants had protective levels of antibody to TT (preterm 100% vs full-term 100% with levels > 0.01 IU/mL), HbPS (82% vs 87%, > 1.0 microgram/mL), and polio serotypes 1 (85% vs 80%, > or = 1:8) and 2 (100% vs 100%, > or = 1:8). Preterm infants were less likely than full-term infants to have protective levels of neutralizing antibody to polio serotype 3 (31% vs 90%, > or = 1:8).


CONCLUSIONS
Extremely premature infants have adequate antibody responses to tetanus and HbOC antigens but may have diminished responsiveness to serotype 3 polio vaccine.
D'Angio
C T
CT
Department of Pediatrics, Strong Children's Medical Center, University of Rochester, NY, USA.
Maniscalco
W M
WM
Pichichero
M E
ME
D000907:Antibodies, Bacterial / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D001426:Bacterial Proteins / Q000008:administration & dosage / Q000276:immunology*; D018073:Haemophilus Vaccines / Q000008:administration & dosage / Q000276:immunology*; D006193:Haemophilus influenzae / Q000276:immunology; D006801:Humans; D007230:Infant, Low Birth Weight / Q000276:immunology; D007231:Infant, Newborn; D007234:Infant, Premature / Q000276:immunology*; D017955:Poliovirus / Q000276:immunology; D011055:Poliovirus Vaccine, Oral / Q000008:administration & dosage / Q000276:immunology*; D013744:Tetanus Toxin / Q000276:immunology; D013745:Tetanus Toxoid / Q000008:administration & dosage / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology*
D000907:Antibodies, Bacterial; D000914:Antibodies, Viral; D001426:Bacterial Proteins; D018073:Haemophilus Vaccines; D011055:Poliovirus Vaccine, Oral; D013744:Tetanus Toxin; D013745:Tetanus Toxoid; D014614:Vaccines, Synthetic; C061963:HibTITER protein, Haemophilus influenzae