World Health Organization (WHO) member states endorsed a new polio eradication strategy 2022-2026 last week that aims to permanently interrupt all poliovirus transmission – both of the wild poliovirus and vaccine-derived cases. 

Meanwhile, WHO Director-General Dr Tedros Adhanom Ghebreyesus said that the discovery of a second wild poliovirus case in Africa, confirmed on 18 May in Mozambique, was “not unexpected” in light of the case previously reported in Malawi. 

But Tedros maintained that member states still have a real opportunity to end polio in the coming years if they “reach every child,” and countries free of the virus build resilient health systems.”

Tedros was speaking at a session on poliovirus eradication shortly before the World Health Assembly’s closure on Saturday.  

Along with the earlier reported case in Malawi, the reported case in Mozambique raises questions over the continued status of the WHO African Region as “wild poliovirus free”.

The wild virus is still endemic in just two countries, Afghanistan and Pakistan. 

But the appearance of the two new wild poliovirus cases in southern Africa, as well as six  new cases in Pakistan in April and May this year, after 15  months in which no cases were reported, underscores the fragility of recent gains.

A WHO spokesperson told Health Policy Watch that Africa’s current wild poliovirus eradication status is not affected at the moment, because these cases are not endemic to Africa, but are linked to virus from Pakistan.  

“We’ve seen this time and again in the past, in other regions as well, where poliovirus was imported into the region, but because it is not endemic to that region, it would not affect the certification status,” said the WHO official.

“That does not make it any less tragic of course, particularly for the children affected and their families, nor does it make the outbreak any less of a public health emergency.  That is why Mozambique immediately declared detection of this outbreak to be a national public health emergency, and the country continues to participate in the multi-country outbreak response with Malawi and other neighbouring countries to urgently stop this outbreak again.”

Vaccine-derived outbreaks increased 

Type II vaccine-derived polio cases continue to be reported in about 20 other countries,  including recent cases in developed countries such as Ukraine and Israel, where the first vaccine-derived polio case in over 30 years was found in March in an ultra-Orthodox Jewish community with low rates of childhood vaccination.  

Overall, a WHO Progress report found a sharp increase in the number of circulating vaccine-derived poliovirus outbreaks between 2018–2021 and “continued vastly insufficient inactivated polio vaccine and oral polio vaccine coverage rates across many polio transition priority countries. 

Even so, the most recent WHO report also found that “compared to 2020, the epidemiological situation improved in 2021, with a 96% decline in cases of poliomyelitis due to wild poliovirus type 1 and a 47% decline in cases due to circulating vaccine-derived poliovirus, globally.

“In endemic areas, five cases due to wild poliovirus type 1 were reported in 2021. This favourable situation must not give rise to complacency; it is a unique opportunity that should be capitalized on through strengthened engagement and support by all partners in the public and civil society sectors,” it adds. 

Civil insecurity, and vaccine hesitancy 

At the same time, the report warns that “the polio eradication programme continues to face both ongoing and emerging challenges, such as the need to catch up with and vaccinate children in endemic reservoir areas who are persistently missed by programmes; insecurity and uncertainty in Afghanistan; the continuing COVID-19 pandemic, which affects polio surveillance and campaigns; and a precarious financial situation adversely affecting the global effort.” 

Member states expressed particular concerns about the resurgence in southern Africa, where wild poliovirus cases have been reported recently in Mozambique as well as Malawi, sparking a massive, five-country vaccination campaign targeting some 23 million children.

As with Malawi, the wildpolio virus strain that has been reported in Mozambique originated  in Pakistan, members said.  However, the appearance of the two cases underscores the fact that the virus is now circulating locally – insofar as neither of the two children had become infected had a travel history.  

The USA said “It strongly supports the WHO efforts for eradicating polio and proposes effective field campaigns in Pakistan, Afghanistan, Malawi and Mozambique. It also expressed concerns about the importation of polio cases in southern Africa”.

Build capacity for countries to produce their own vaccines 

Western African nation republic of Benin speaking on behalf of 47 African states said asked for the capacity building in the health systems including producing local vaccines to end polio. 

It said member states are committed to eradicating polio till 2023 but results so far are fragile, adding that governments have to build strong policies and sustainable financial programs to maintain the success against polio. 

Regional Director of the WHO Africa region, Dr Matshidiso Moeti, said member states need to prioritize the commitments to end polio with political commitment and increased domestic funding. 

She urged a strengthened surveillance system to be the best defence against wild and vaccine-derived polio cases.

Moeti said that the Mozambique case, like that in Malawi, was “genetically linked to Pakistan,” and  “does not affect the WHO African region wild polio-free certification for now. 

However, she acknowledged that the continued appearance of cases would in fact pose an obvious  threat to Africa’s polio-free status, saying, “the governments of Malawi and Mozambique are taking determined and swift action with the support of GPEI partners and action of their neighbours to address a setback which threatens decades-long hard work and region’s certification status.”

Dr Ahmed Ali Mandhari, regional director of WHO’s Eastern Mediterranean Region to which Pakistan and Afghanistan belong, said that fragile campaigns have given a chance to survive the wild poliovirus in Pakistan and Afghanistan. However, the health systems and polio workers are doing impressive work in difficult regions where they face deadly attacks. 

He further said that added investments in polio eradication programs can help wipe out the vaccine-derived cases “on the fast track” from conflict zones, such as Somalia, Yemen, and Sudan. 

In its statement, Gavi, the Vaccine Alliance, said full implementation of the eradication plan for 2022-26 means reaching 1.71 million more children, mostly in the AFRO and EMRO regions,  who have not yet been vaccinated at all.

Gavi said the COVID-19 pandemic disrupted immunization activities across the world and widened the vaccine equity gaps as well. 

Wildvirus re-emergence due to fragile anti-polio drives

At the same time, Rotary International, a WHO and GAVI partner said although the lowest numbers of polio ever were reported in 2021, the virus re-emerged in 2022 because of fragile anti-polio drives. 

 “The fragility in 2022 of anti polio drives led to the emergence of cases in Malawi and Mozambique,” said the Rotary delegate to the WHA. He  and called countries to address gaps in their immunization programs”.

Rotary asked the member states to address immunization gaps in their respective polio programs. 

Pakistan also re-affirmed its commitment to ending polio.  The country has proposed five years program with the financial assistance of above 10 million dollars to end polio from the country.

The African nation Malawi said the country has 2.9 million population of children and it has submitted a budget proposal to increase efforts against polio which resurge after years. 

It said the polio response program and Emergency Operations Center are working and the plan is to achieve zero polio cases in Malawi.   

Ten recommendations – including global polio integration into health systems 

Another WHO evaluation of progress on poliomyelitis presented ten recommendations to member states for accelerating eradication efforts. 

These include developing a global plan to integrate polio eradication and vaccination efforts into national health systems. 

Traditionally polio eradication has been funded separately by a massive donor driven effort under the auspices of the Global Polio Eradication Initiative (GPEI), and managed vertically – although behind the scenes, better-funded polio teams sometimes also were used by national health systems to administer other vaccine efforts in tandem. 

The WHO plan aims to better include polio activities in relation to other WHO investments in primary health care, vaccine-preventable diseases, and emergency response, as well as broader, global polio and polio transition efforts.

Member states have a real opportunity to end polio by 2023, adding that 50 countries have the support of GPEI and each has challenges ahead. 

“Countries still fighting with the virus must reach every child, and countries free of the virus must build resilient health systems,” said Dr Tedros. 

Image Credits: Sanofi Pastuer/Flickr.