Despite the big success this year in the eradication of wild poliovirus in the African region, the COVID-19 crisis has seen a temporary interruption of polio vaccine programmes. This has led to a rise in vaccine-derived polio cases which, are more likely to occur when vaccine coverage is weaker, WHO and African Region health officials told World Health Assembly (WHA) member states in a wide-ranging review of WHO’s massive two-decade polio eradication effort.

The prospect of a forthcoming COVID-19 vaccine, meanwhile, underlines the important role the programme can play, WHO’s Dr Michel Zaffran, director of the Polio Eradication Programme, said at the WHA session. He specified that adapting national polio eradication teams to COVID-19 prevention and eventually immunization was critical.

“Since July … polio immunization campaigns have resumed under strict infection control protocols in endemic impoverished countries,” he noted, adding that “polio staff have rapidly pivoted to support COVID-response activities, helping with disease surveillance, contact tracing, and educating communities on physical distancing and hygiene.”

Zaffran warned, however, that inadequate vaccine coverage in areas at risk of outbreak mean that “risks are high”.

“Last week, UNICEF and WHO issued a global call,” he said, “for the international community to ensure that the financial resources needed to respond to outbreaks are made available.”

WHO’s Sylvie Briand confirmed that WHO is looking at options to ensure the continued cross-fertilizing between polio eradication and the COVID battle.

She said: “We know that innovative partnerships, mechanisms and platforms, developed through the ACT Accelerator can be leveraged for long term investment in pandemic preparedness, including the research, development and availability of innovative influenza pharmaceutical products.

“So … learning from the COVID-19 crisis, we are looking at options to ensure the continent continues cross-fertilising between programmes.”

“There is an opportunity to link the transition of polio-funded assets with COVID-19 recovery efforts to build back better,” said a representative of the UN Foundation, one of the partners in the polio eradication effort.

Integrating Polio Programmes with National Health Systems

Over the longer term, better integration of polio programmes with national health systems remains a key priority, donor states have emphasized.

“Polio programmes have become cornerstones of the national health system, including their response to COVID 19. It is essential that we progress on integration of the project assets into the national health programmes and have polio vaccines integrated,” said Germany’s WHA representative.

The wide-ranging conversation followed WHO’s presentation to member states of a progress report on its eradication effort. A parallel WHO report covers polio “transition planning” – shifting polio staff and resources into broader Ministry of Health vaccines and primary health care activities.

The Global Polio Eradication Initiative (GPEI) is one of the WHO’s and the world’s largest single global health efforts, with a separate budget of US$4.2 billion, that employs teams embedded in the national health systems of countries in Africa, the Eastern Mediterranean region, and the Western Pacific (Asia). Gavi, the Vaccine Alliance has contributed more than US$180 million to the GPEI, and has pledged an estimated US$800 million in support of inactivated polio vaccines (IPV), as part of GPEI’s Polio Endgame Strategy.

Polio Programmes: From Downsizing to Repurposing

Only a couple of years ago, the main corridor conversation inside WHO was how to dramatically downsize the polio programme – including termination or transition of polio team members to other positions – as eradication goals were progressively met.

Now, talk has pivoted to a conversation about how to repurpose those same programmes and teams to help deliver COVID-19 vaccines when these become available – a new and equally momentous task.

Along with that, donors and countries are talking about the importance of better, long-term “integration” of the vertically-designed, donor-driven polio programme into countries’ broader immunization plans and national health systems.

De facto, polio teams are already deeply involved in national health services delivery of a much broader array of vaccines – including the 3-in-1 Td/IPV vaccine (protecting against tetanus, diphtheria and polio).

But until the COVID-19 pandemic, the relevance of the polio programme to vaccine services more broadly was not well understood.

Now that COVID has made this more obvious, the challenge of supporting and funding the institutional rea-lignment of resources remains. With this support in place, national ministries and immunization programmes can staff and fully budget for tasks being fulfilled by the polio programme, as part of primary health care systems.

New Low Risk Oral Vaccine Rollout Urged

A new oral vaccine that is expected to have a substantially lower risk of generating vaccine-derived poliovirus (VDPV) cases was also announced to replace a predecessor that had been used until 2016. The new vaccine is expected to be rolled out, beginning in January 2021 and will be deployed under emergency use.

While oral polio vaccines (OPV) are generally safe and effective, on rare occasions the live poliovirus component can cause infection.

But since 2016, when the earlier OPV was withdrawn, some 49 outbreaks of a genetically distinct circulating VDPV have been reported in 21 countries, including in Africa and the Eastern Mediterranean and Western Pacific Regions.

“Unfortunately, 2020 has seen a dramatic increase in outbreaks of circulating VDPV in Africa and Asia,” said Dr Zaffran. Commenting on the deployment of the new vaccine, he added: “This must be complemented by existing tools, including efforts to strengthen routine immunisation with a second dose of IP.”

Increasing Risk of VDPVs in Migrants to Polio-Free Countries

Several countries – including those certified polio-free – reported an increased risk of polio infection in vulnerable populations, caused by COVID-impeded vaccination campaigns.

Malaysia is a country that was declared polio-free in 2000, however it warned that delays in vaccination campaigns pose a risk to newborns and migrants. The representative said that the GPEI and international organisations need to assist countries to “address the issues of highly-mobile, cross-border populations.”

A representative from Iran cited a “growing concern due to illegal immigration” with neighbouring countries. Wild polioviruses still exist in Afghanistan, which sits along Iran’s eastern border, and experienced an outbreak of VDPV type 2 earlier this year.

The Malaysia representative also said: “Undocumented migrants are at an even greater risk of missing not only routine immunisation, but also polio vaccination campaigns. Efforts to address these marginalised populations will benefit polio control.”

Image Credits: UNICEF Ethiopia/Mulugeta Ayene 2018, WHO.