Advances toward eradication: U.S. taking inventory of potential poliovirus materials
TrishaKorioth, Staff Writer
For Your Information
Major strides toward complete polio eradication have been made, but crucial next steps
lie ahead in the World Health Organization (WHO) Global Poliovirus Eradication Initiative
Since the comprehensive GPEI launched in 1988, wild poliovirus type 2 was declared
eradicated in 2015, and no cases of wild poliovirus type 3 have been detected since
2012. Only 29 cases of wild poliovirus type 1 were identified at the end of 2018.
Efforts will not end once wild poliovirus has been eradicated. Activities will be
needed to minimize the risks of wild and vaccine poliovirus re-introduction and the
emergence of circulating vaccine-derived poliovirus.
To eliminate the rare risk of vaccine-associated paralytic polio and circulating vaccine-derived
poliovirus, a choreographed global switch to bivalent (types 1 and 3) oral poliovirus
(OPV) vaccine was introduced in 2016 along with at least one dose of inactivated poliovirus
(IPV) vaccine in areas using bivalent OPV. Trivalent OPV no longer is used. For details,
The Centers for Disease Control and Prevention (CDC) National Authority for Containment
of Poliovirus is overseeing an initiative to ensure that polioviruses retained by
U.S. laboratories and facilities are accounted for and safely contained.
A national CDC inventory survey recently was issued to facilities in the U.S. that
test, extract, handle or store biological samples from humans, experimentally infected
animals, sewage or environmental waters. Because these materials potentially could
contain poliovirus, facilities that continue to handle or store poliovirus will be
expected to meet all biological risk management requirements, according to the CDC.
The inventory is part of a WHO global objective to eventually contain the three types
of poliovirus, beginning with poliovirus type 2. Countries are working to meet four
pillars of containment:
Identify infectious and potentially infectious poliovirus materials.
Destroy unneeded poliovirus materials.
Transfer needed poliovirus materials to designated poliovirus-essential facilities.
Contain poliovirus type 2 in compliance with WHO global action plan requirements at
designated poliovirus-essential facilities.
IPV is used for routine polio immunization in the U.S. and many other countries, but
bivalent OPV continues to be used in some areas of the world.
According to the Red Book, fully immunized individuals who will be traveling to or from areas where polio is
endemic, who will reside for four or more consecutive weeks in countries with ongoing
poliovirus transmission or who plan to travel from these countries to polio-free countries
should receive an additional dose of IPV between four weeks and 12 months before travel.
Travelers who depart from countries with ongoing poliovirus transmission with fewer
than four weeks’ notice who have not been vaccinated with OPV or IPV within the previous
four weeks to 12 months should receive a dose by the time they depart the country.
Refer to Red Book online for updates and information, http://bit.ly/RedBookPolio.