The World Moves Closer to Polio Eradication with Oral Vaccine ‘Switch’ and Containment of Laboratory Samples
By Dave Ross, ScD, President and Chief Executive Officer, The Task Force for Global Health
With polio eradication on the horizon, The Task Force for Global Health has been assisting the World Health Organization (WHO) and U.S. Department of Health and Human Services (HHS) in coordinating immunization and containment activities vital to wiping out the disease permanently.
From April 17-May 1, The Task Force supported the synchronized ‘switch’ in the type of oral polio vaccine used in more than 150 countries. Countries changed from a trivalent (containing weakened versions of types 1, 2, and 3 polioviruses) to bivalent oral polio vaccine (containing types 1 and 3). The change took place because the type 2 strain has been eradicated. During the two weeks of the ‘switch,’ The Task Force provided technical assistance to countries in switching vaccines and had representatives at WHO headquarters in Geneva, Switzerland, and in Nigeria, Ghana, Kenya, and Madagascar.
After polio is eradicated, the oral polio vaccine will be phased out in favor of an injectable polio vaccine to ensure that polioviruses do not emerge again.
The Task Force has been working with WHO since 2014 on coordinating the ‘switch.’ Last May, it hosted a ‘switch’ planning meeting of 80 trainers and consultants from 35 countries. The Bill & Melinda Gates Foundation supports Task Force activities focused on global polio eradication.
Laboratory Containment Vital to Polio Eradication
In addition to supporting the ‘switch,’ The Task Force is assisting HHS with polio eradication in the United States by serving as the secretariat for the U.S. National Certification Committee. This group is charged with ensuring samples of eradicated polioviruses are contained in U.S. facilities and not reintroduced into the population.
The risk of poliovirus spread from U.S. facilities is low. All countries have established National Certification Committees as part of the Polio Eradication and Endgame Strategy.
The certification process consists of initially surveying 120 U.S. laboratories that had been previously identified as holding wild poliovirus samples. If these facilities still hold samples, these laboratories are asked to destroy, inactivate, or transfer their samples to designated facilities. The Task Force supported the original survey of U.S. laboratories in 2002-03 that was conducted by Walter Dowdle, PhD, and colleagues. The National Certification Committee is initially focusing on containment of type 2 poliovirus by the end of July 2016 and will later focus on containing all polioviruses by 2019.
As the secretariat for the National Certification Committee, The Task Force identified eminent public health and scientific experts to serve on the committee. It is also convening the committee regularly throughout the year. Olen Kew, PhD, former associate director for Global Laboratory Science at Centers for Disease Control and Prevention (CDC), serves as the National Poliovirus Containment Coordinator.
“The certification process must be done independently of the work of CDC,” said Kew. “The Task Force–as an independent entity–plays an extraordinarily important role by ensuring that the certification process is handled ethically and without reproach.”