A groundbreaking study released last week shows that a single injectable dose of inactivated polio vaccine (IPV) along with bivalent oral polio vaccine could protect up to 90 percent of children from polio and strengthen community protection against the disease.
[Photo: Dr. Edwin Asturias]
This research, led by Dr. Edwin Asturias at the Center for Global Health in the Colorado School of Public Health, provides the evidence behind the worldwide switch to a polio vaccine strategy by demonstrating that new schedule of injectable vaccine, when combined with bivalent oral vaccine, protects children faster and is more reliable than the oral vaccine, alone.
Most underdeveloped countries, until now, solely used three-component oral polio vaccines given over multiple months. While effective, poor health and sanitation has meant that many children need multiple doses to achieve the necessary protection. Not only is this more impractical and risky, but the type 2 component in the trivalent oral vaccine has also been the source of most of the rare outbreaks of vaccine-derived polio.
Because the type 2 wild polio has not been reported anywhere since 1999, all OPV-using countries switched to the bivalent polio vaccine, which does not include the type 2 component. The bivalent form will be coupled with the IPV in the primary immunization series, providing faster, stronger protection.
The study was sponsored by FIDEC, funded by the Bill & Melinda Gates Foundation, collaborated by stakeholders of the Global Polio Eradication Initiative, and conducted over 12 months with more than 1,400 subjects in Guatemala, Colombia, Panama and the Dominican Republic.
The findings have implications for routine immunization today, as well as polio outbreak response strategies in the future. It also confirms the importance of the polio vaccine switch strategy and the feasibility of achieving a polio-free world.
Read more here.