Ma. Koenig et al., DURATION OF PROTECTIVE IMMUNITY CONFERRED BY MATERNAL TETANUS TOXOID IMMUNIZATION - FURTHER EVIDENCE FROM MATLAB, BANGLADESH, American journal of public health, 88(6), 1998, pp. 903-907
Objectives. Although maternal tetanus immunization has been shown to b
e highly effective in the prevention of neonatal tetanus, unresolved q
uestions remain concerning the required minimum number of doses and th
e resulting duration of effective: immunity. This study examined the d
uration of effective immunity against neonatal tetanus provided by mat
ernal tetanus immunization. Methods. A randomized, double-blind choler
a vaccine trial of 41 571 children and nonpregnant adult women carried
out in 1974 in the Matlab comparison area of rural Bangladesh provide
d a unique opportunity to address dose and immunity issues. Results. C
hildren of women who received either 1 or 2 injections of tetanus toro
id experienced 4- to 14-day mortality levels consistently lower than t
hose of children of unimmunized mothers. Analysis of neonatal-tetanus-
related mortality showed that 2 injections of tetanus toroid provided
significant protection for subsequent durations of up to 12 or 13 year
s. Conclusions. The data demonstrate that a limited-dose regimen of ma
ternal tetanus toroid provides significant and extended protection aga
inst the risk of neonatal tetanus death.