Maternal antibodies to pneumolysin but not to pneumococcal surface protein A delay early pneumococcal carriage in high-risk Papua New Guinean infants.
Immunization of pregnant women can be an efficient strategy to induce early protection in infants in developing countries. Pneumococcal protein-based vaccines may have the capacity to induce pneumococcal serotype-independent protection. To understand the potential of maternal pneumococcal protein-specific antibodies in infants in high-risk areas, we studied the placental transfer of naturally acquired antibodies to pneumolysin (Ply) and pneumococcal surface protein A family 1 and 2 (PspA1 and PspA2) in relation to onset of pneumococcal nasopharyngeal carriage in infants in Papua New Guinea (PNG). In this study, 76% of the infants carried Streptococcus pneumoniae in the upper respiratory tract within the first month of life, at a median age of 19 days. Maternal and cord blood antibody titers to Ply (rho = 0.824, P < 0.001), PspA1 (rho = 0.746, P < 0.001), and PspA2 (rho = 0.631, P < 0.001) were strongly correlated. Maternal pneumococcal carriage (hazard ratio [HR], 2.60; 95% confidence interval [CI], 1.25 to 5.39) and younger maternal age (HR, 0.74; 95% CI, 0.54 to 1.00) were independent risk factors for early carriage, while higher cord Ply-specific antibody titers predicted a significantly delayed onset (HR, 0.71; 95% CI, 0.52 to 1.00) and cord PspA1-specific antibodies a significantly younger onset of carriage in PNG infants (HR, 1.57; 95% CI, 1.03 to 2.40). Maternal vaccination with a pneumococcal protein-based vaccine should be considered as a strategy to protect high-risk infants against pneumococcal disease by reducing carriage risks in both mothers and infants.
Francis
Jacinta P
JP
Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea.
Richmond
Peter C
PC
Pomat
William S
WS
Michael
Audrey
A
Keno
Helen
H
Phuanukoonnon
Suparat
S
Nelson
Jan B
JB
Whinnen
Melissa
M
Heinrich
Tatjana
T
Smith
Wendy-Anne
WA
Prescott
Susan L
SL
Holt
Patrick G
PG
Siba
Peter M
PM
Lehmann
Deborah
D
van den Biggelaar
Anita H J
AH
D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D001426:Bacterial Proteins / Q000276:immunology*; D002353:Carrier State / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D005260:Female; D006801:Humans; D007112:Immunity, Maternally-Acquired; D007231:Infant, Newborn; D009305:Nasopharynx / Q000382:microbiology; D010219:Papua New Guinea / Q000453:epidemiology; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D011247:Pregnancy; D015995:Prevalence; D013296:Streptococcus pneumoniae / Q000276:immunology* / Q000302:isolation & purification; D013301:Streptolysins / Q000276:immunology*; D055815:Young Adult
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D013301:Streptolysins; C032290:plY protein, Streptococcus pneumoniae; C051592:pneumococcal surface protein A