Rakesh Kumar
Tetanus toxoid is one of the most successful vaccines used in immunization programme almost all over the world. Neonatal tetanus can be prevented by immunizing women of childbearing age with tetanus toxoid, either during pregnancy or outside of pregnancy. Tetanus vaccine is used either in mono or in combination with other antigens i.e. Diphtheria, Pertussis (whole cell or acellular), Hepatitis B, Haemophilus influenzae B, Inactivated polio vaccine etc. Tetanus toxoid is produced batch-wise using complex media, often containing poorly defined components. Therefore, batch related quality control to guarantee safety and potency is a statutory requirement. In the new concept, quality control is seen as an instrument to monitor consistency of the critical steps in the production process and testing of vaccines. Monitoring consistency places emphasis on in-vitro methods, since in-vivo tests are less appropriates (expensive, time consuming and inaccurate) for this purpose. Immunochemical techniques may include the use of polyclonal antibodies for direct ELISA or monoclonal antibodies in capture ELISA and immunoblotting to indicate local differences in antigenicity.