PERFORMANCE AND POTENCY OF TETANUS TOXOID - IMPLICATIONS FOR ELIMINATING NEONATAL TETANUS

Neonatal tetanus (NT) is a major cause of mortality in developing coun tries with over 400000 deaths estimated to occur annually. WHO has ado pted the goal of eliminating NT worldwide, and a major strategy for if s prevention is the administration of at least two properly spaced dos es of tetanus toroid (TT) to women of childbearing age in high-risk ar eas to protect passively their newborns at birth. In certain countries the locally produced TT vaccine has been shown to be subpotent, while other countries have reported NT among infants born to vaccinated wom en. An extensive review of production and quality control procedures w as carried out between 1993 and 1995 in 8 of 22 TT-producing countries that also report NT cases, with a more superficial assessment being c arried out in the remaining 14 countries. Only 4 of the 22 countries h ave a functioning national control authority to monitor TT production and vaccine quality. A total of 80 TT lots from 21 manufacturers in 14 of the 22 NT-reporting countries were tested for potency. Of these, 1 5 lots from eight manufacturers in seven countries had potency values below WHO requirements. TT potency can also be compromised by improper vaccine handling. To eliminate neonatal tetanus worldwide requires as surance that all doses of TT meet WHO production and quality,requireme nts and that the field effectiveness of TT is monitored through system atic NT case investigations and assessment of coverage.