1) What is ATT?
2) Type of immune response involves
3) Why it is given 2 dose in primid pregnancy
Tetanus vaccine is an inactivated toxin (toxoid) made by growing the bacteria in a liquid medium and purifying and inactivating the toxin. It involves activation of type II Immune response
It is administer once the quickening felt and can be repeated 2-3 months after first injection in primid women as a booster injection. (Usually 5th and 7th months of pregnancy)
For the first time injection, it will stimulate the production of IgM and activation of memory B cell. This IgM could not cross the placenta, hence it action mainly for the protection of the mother.
During the second @ booster dose, it will stimulate the production of IgG. This antibody can cross the placenta and it can give protection for the baby.
Examples of importance of ATT is illustrated in this case.
For woman who undergoes caesarean section, they are always at risk of developing the tetanus from contaminated surgical instrument. ATT are meant to prepare the mother for this event.
As for the baby, the most common source of infection is during the cutting of umbilical cord especially with inadequate sterility of scissors.
Notes: It is different from Anti tetanus human immunoglobulin which are preparation containing IgG immunoglobulin derived from plasma of donors sensitized to tetanus toxoid. It acts by The IgG antibodies acts to neutralize the free circulating exotoxisn of clostridium tetani and prevent its fixation in tissue and its consequences.