Inactivated poliovirus vaccine (IPV), developed in the USA by Jonas Salk in the 
early 1950s, was field tested in 1954, and found to be safe and effective. The 
year 2004 marks the golden jubilee of this breakthrough. From 1955 IPV was used 
extensively in the US and polio incidence declined by more than 95 per cent. 
However, in 1962, when oral poliovirus vaccine (OPV) became available, the 
national policy was shifted to its exclusive use, for reasons other than science 
and economics. The World Health Organisation (WHO) also adopted the policy of 
the exclusive use of OPV in developing countries. Thus IPV fell into disrepute 
in much of the world, while Northern European countries continued to use it. New 
research led to improving its potency, reducing its manufacturing costs and 
combining it with the diphtheria-tetanus-pertussis (DTP) vaccine to simplify its 
administration and reduce programmatic costs. All countries that chose to 
persist with IPV eliminated poliovirus circulation without OPV-induced polio or 
the risk of live vaccine viruses reverting to wild-like nature. IPV is highly 
immunogenic, confers mucosal immunity and exerts herd protective effect, all 
qualities of a good vaccine. It can be used in harmony with the extendend 
programme on immunization (EPI) schedule of infant immunisation with DTP, thus 
reducing programmatic costs. During the last ten years IPV has once again 
regained its popularity and some 25 industrialised countries use it exclusively. 
The demand is increasing from other countries and the supply has not caught up, 
leaving market forces to dictate the sale price of IPV. Anticipating such a turn 
of events India had launched its own IPV manufacturing programme in 1987, but 
the project was closed in 1992. Today it is not clear if we can complete the job 
of global polio eradication without IPV, on account of the genetic instability 
of OPV and the consequent tendency of vaccine viruses to revert to wild-like 
properties. The option to use IPV is complicated since it is not yet licensed in 
India, we do not manufacture it and imported vaccine would be prohibitively 
costly. However, in this golden jubilee year we have much to celebrate as the 
global eradication of wild polioviruses is within sight. Had we strictly 
followed the principles of science and health economics, perhaps we could have 
achieved success earlier and cheaper, with the absence of vaccine-induced polio 
as the bonus.