How often to vaccinate?
Furthermore, how often to vaccinate with a tetanus booster is simply guesswork. Apparently too much of this vaccine can backfire. Tetanus toxoid appears to afford protective effect up to 3 or more years following vaccination. However, in Tanzania researchers have reported that the serum antibodies against tetanus toxin in 7 neonates who were infected with tetanus were found to be 4-13 times higher than the presumed protective level. All but one of the mothers had been vaccinated with tetanus toxoid in pregnancy. Two mothers who had received booster doses during pregnancy had anti-toxin concentrations 100-400 times the presumed protective level. The toxin dose may overwhelm the pre-existing anti-toxin level and produce disease and lead to an ineffective immune response.
