Addressing the Re-emergence of Poliovirus

Eradicating polio is perhaps the largest worldwide public health initiative in history, and through extensive vaccination efforts, one of the three poliovirus types (poliovirus type 2) has nearly been exterminated while the incidence of polio has declined to the lowest levels ever. Unfortunately, poliovirus has begun to re-emerge in once polio-free countries and new vaccination and therapeutic strategies are being considered. Challenges are many but critical is maintaining good surveillance and sufficient supplies of Oral polio vaccine (OPV), as well as Inactivated polio vaccine (IPV) which ultimately will replace OPV when wild poliovirus transmission has been interrupted. There is a need to develop enhanced polio vaccine cell lines that can increase vaccine titers and production to provide the means lower the cost of vaccine manufacture, to meet worldwide demand, and to address vaccine efficacy by preventing vaccine losses due to ‘cold chain’ requirements implicit in delivering vaccines to third world nations. In addition, there is a need to develop safe and effective antivirals to address the incidence of OPV ‘shedders’ and in achieving and maintaining global eradication and containment of poliovirus.