Vaccines Global Summit

Polio vaccines have played a monumental role in the global battle against polio, a highly infectious viral disease that can cause paralysis and even death in extreme cases. Polio primarily affects children under five years old and, prior to the advent of vaccines, instilled widespread fear, devastating many countries around the world.

There are two main types of polio vaccines: the oral polio vaccine (OPV) and the inactivated polio vaccine (IPV). The OPV was introduced in the 1960s by Albert Sabin and is administered in drops to introduce a weakened, live poliovirus into the body. This vaccine creates widespread immunity in the gut, where the poliovirus replicates, thereby reducing virus circulation within the community. OPV is easy to deliver and inexpensive, making it the centerpiece of vaccination campaigns aimed at eradicating polio worldwide, particularly in developing countries. However, in a small minority of vaccinees, the live virus in OPV can mutate over time and become vaccine-derived polio, posing a barrier to the ultimate goal of eradication.

The IPV, developed by Jonas Salk in the 1950s, uses an inactivated (killed) form of the poliovirus and is administered through injection. It induces effective systemic immunity and cannot cause polio at all, making it the preferred option in countries that have already eliminated wild poliovirus, as population immunity can be maintained without the risk of vaccine-derived cases. However, IPV is more expensive and requires skilled health professionals for administration, which makes it less ideal for mass immunization in resource-scarce settings.

Together, these vaccines have significantly reduced polio cases worldwide by more than 99%, bringing the world closer to eradicating the disease. Continued vaccination efforts are essential, particularly in areas where wild poliovirus still exists and where vaccine-derived poliovirus is likely to occur. The remarkable success of polio vaccines highlights the power of global collaboration in disease eradication efforts and stands as one of the most significant public health achievements in history.