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Type 2 Polio Eradicated


Polio-Free World in Sight as Largest Vaccine Rollout in History Kicks Off

GENEVA, 14 April 2016 – Next week marks the beginning of the largest and fastest globally coordinated rollout of a vaccine into routine immunization programs in history. Between 17 April and 1 May, 155 countries and territories around the world will stop using the trivalent oral polio vaccine (tOPV), which protects against all three strains of wild poliovirus, and replace it with bivalent OPV (bOPV), which protects against the remaining two wild polio strains, types 1 and 3. This effort will provide better protection for children against polio, particularly those most vulnerable to infection.

This transition, referred to as the global vaccine “switch,” is possible because type 2 wild polio has been eradicated. The switch has been recommended by the Strategic Advisory Group of Experts on Immunization and endorsed by the World Health Assembly as a critical component of the polio endgame strategy.

“We’re closer than ever to ending polio worldwide, which is why we are able to move forward with the largest and fastest globally synchronized vaccine switch ever,” said Michel Zaffran, Director of Polio Eradication at the World Health Organization. “It is a massive undertaking, but it is testimony to how much progress is being made toward achieving a lasting polio-free world and to the commitment of all countries to make this dream a reality.”

The oral polio vaccine (OPV) has been used to stop polio in most of the world. On very rare occasions in under-immunized populations, the live weakened virus contained in OPV can mutate and cause circulating vaccine-derived polioviruses (cVDPV). More than 90% of cVDPV cases in the last 10 years have been caused by the type 2 vaccine strain. Withdrawing tOPV and replacing it in routine immunization programs with bOPV will eliminate the risks associated with the type 2 vaccine strain and, just as importantly, boost protection against the two remaining wild strains of the virus.

The switch must be globally synchronized because if some countries continue to use tOPV it could increase the risk of the spread of type 2 poliovirus to those no longer using tOPV. The switch is the first major step toward the eventual removal of all OPV after wild polio transmission has been stopped.

“This is an extremely important milestone in achieving a polio free world,” said Reza Hossaini, Chief of Polio at UNICEF. “Hundreds of thousands of vaccinators and health workers have been trained for the switch to happen quickly and effectively, so that children everywhere can be protected from this devastating disease.“

To ensure that the switch takes place as planned, thousands of independent monitors will confirm the absence of tOPV at public and private service facilities and cold chain stores.

“The switch is a massive undertaking and is only possible due to the tremendous collaboration of country governments, GPEI partners, and the independent monitors. It is another example of the program moving in the right direction toward global eradication,” said Jay Wenger, Director of the Polio Program at the Bill & Melinda Gates Foundation.

In countries at higher-risk of a polio outbreak, a dose of inactivated polio vaccine (IPV) has been added to routine immunization schedules, in addition to bOPV, to further boost immunity. To protect against the very small risk of an outbreak of cVDPV type 2 after the switch, a global stockpile of monovalent OPV (mOPV) type 2 is ready to be dispatched if an outbreak occurs.

“The stockpile of mOPV type 2 is like an insurance policy in case there is an outbreak,” said Stephen Cochi, Senior Adviser to the Director of the Centers for Disease Control and Prevention’s Global Immunization Division. “A lot of time has been spent evaluating the possible risks and minimizing them.”

The switch is a significant milestone in the effort to achieve a polio-free world. In 2015, there were fewer cases reported in fewer countries than ever before. This year, the focus is on reaching every child with the polio vaccine and stopping the virus in its final strongholds. In order for that to happen, donors must continue to invest in the eradication effort.

“When Rotary started the campaign to end polio, more than 350,000 children were paralyzed every year by this deadly virus,” said Michael K. McGovern, Chair of Rotary’s International PolioPlus Committee. “This switch is an important step, but we must maintain our support until every last child is safe from this disease.”

Media contacts:

Oliver Rosenbauer, World Health Organization; +41 79 500 6536;

Francesca Heintz, Global Health Strategies; +1 914 588 0823;

John Butler, Global Health Strategies; +1 917 573 1339;

 Note to editors:

The Global Polio Eradication Initiative is spearheaded by national governments, WHO, Rotary International, the US Centers for Disease Control and Prevention (CDC) and UNICEF, and supported by key partners including the Bill & Melinda Gates Foundation. Since 1988, the incidence of polio has been reduced by more than 99.9 percent. At the time, more than 350,000 children were paralyzed every year, in more than 125 endemic countries. Today, only two countries remain that have not stopped endemic transmission of wild polio: Pakistan and Afghanistan. In 2015, 74 cases of wild poliovirus and 32 cases of circulating vaccine-derived poliovirus were recorded.

Polio Eradication Progress

 The world is closer than ever to eradicating polio with only 10 cases of wild polio to date as of April 14th in 2016. The two endemic countries have 8 cases in Pakistan and 2 cases in Afghanistan, a reduction of 60% for the same period in 2015. The End Game Strategy 2013-18 aimed at delivering a polio free world by 2018 at a cost of $5.5 billion over this period. However due to the continuing wild polio transmission in two endemic countries this year an additional $1.5 billion is currently projected to be necessary to finish the job in 2019. This is because if transmission of the polio virus is stopped in 2016, vaccinations must continue for another three years to secure certification of a polio free world.

Between 17 April and 1 May, every country in the world currently using oral poliovirus vaccine (OPV) must withdraw the trivalent vaccine (tOPV) and replace it with the bivalent vaccine (bOPV). This programme involves 155 countries, this will continue to protect infants from poliovirus types 1 and 3 while withdrawing the type 2 component, thereby mitigating the risk of seeding new type 2 circulating vaccine-derived poliovirus (cVDPV2). With careful planning and thorough oversight, the switch will represent a huge achievement for the polio programme and will provide a basis for the eventual withdrawal of all OPV, following eradication of poliovirus types 1 and 3.

The Global Polio Eradication Initiative partners’ press release on the switch is attached for information.

As part of the End Game Strategy for polio eradication, the inactivated polio vaccine (IPV) is being introduced into the routine immunization systems of every country that currently uses the oral polio vaccine (OPV). To date 96 countries have introduced IPV, which will help to boost immunity against all types of poliovirus, giving children higher protection against paralytic polio. This is the most ambitious, largest and fastest globally synchronised vaccine introduction in history.

The gains in polio eradication made to date are precarious and constantly at risk of being reversed. Polio remains endemic in two countries – Afghanistan and Pakistan. Eight countries are considered to be vulnerable Cameroon, Equatorial Guinea, Ethiopia, Iraq, Nigeria, Somalia, South Sudan and Syria.

Until poliovirus transmission is interrupted in the endemic countries, all countries remain at risk of importation of polio, especially vulnerable countries with weak public health and immunization services, and travel or trade links to endemic countries. Circulating vaccine-derived poliovirus is causing outbreaks in Madagascar, Guinea, Myanmar and Ukraine.

It is imperative that Rotarians stay engaged and help raise funds for polio eradication by 2019. Failure to eradicate polio could result in as many as 200,000 new cases every year within a decade all over the world. Rotary started the programme in 1985 and our support must not waiver now. We have vaccinated two billion children and saved over 13 million children contracting polio, a remarkable achievement.  Please help raise the funds required and remember that every pound raised will receive two pounds from the Bill & Melinda Gates Foundation.

Judith Diment

Chair Polio Eradication Advocacy Task Force and Member of International PolioPlus Committee

April 14 2016