Poliomyelitis and Child Paralysis
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KeywordsEradication Immunization Global health
On 12 April 1955, church bells rang out across the United States to celebrate the long-awaited announcement that the largest clinical trial then undertaken had confirmed the safety and efficacy of the first-ever vaccine against polio (Oshinsky 2005). A mere 2 years earlier, 36,000 children across the United States had been killed or paralyzed by poliomyelitis. Estimates of worldwide polio incidence suggest that before the discovery of Jonas Salk’s intravenous polio vaccine (IPV), there were nearly 600,000 cases of the disease every year (Smallman-Raynor and Cliff 2006). The relief from fear brought about by the vaccine was palpable across the world: Salk had babies named after him, was fêted by movie stars, and received thousands of gifts and messages from distant admirers (including a 209-foot-long telegram signed by 8,000 grateful residents of Winnipeg, Canada).
Poliomyelitis – a name derived from Greek for “inflammation of the grey marrow” – is caused by infection with poliovirus, a type of enterovirus found throughout the world. Wild poliovirus is transmitted primarily via the fecal-oral route through which individuals swallow water or food that has come into contact with contaminated water or feces. Consequently, the environmental context plays a significant role in determining who contracts polio and at what age. In socioeconomic contexts with fragile or nonexistent public sanitation systems, infants primarily contract asymptomatic cases of polio in which the body develops sufficient antibodies to confer lifelong immunity. In these cases, the poliovirus lingers in the digestive tract, primarily in the small intestine, where the host’s immune system produces antibodies that counteract the virus before it is excreted several weeks after initial infection. In approximately 1 in 200 cases, the virus spreads into the central nervous system, replicating in the gray matter of the spinal cord, the brain stem, or the motor cortex, where it causes lesions which, if extensive, can affect the motor nerve control of muscles and result in paralysis.
The polio epidemics of mid-twentieth-century America were, counterintuitively, the result of improved public sanitation; children were not exposed to wild poliovirus until they were older and when the disease is more likely to result in paralysis and can be fatal. In many parts of the Global South, where sanitation systems are weak, poliomyelitis has rarely been seen as a major health concern due to the earlier exposure of infants to the wild poliovirus when symptoms are relatively mild and few cases lead to paralysis.
More than 60 years after the successful Salk trial, the incidence of polio and paralysis is radically different. In 2017, there were a mere 22 cases of poliomyelitis derived from wild poliovirus transmission globally and a further 96 cases of circulating vaccine-derived poliovirus linked to the use of the Sabin oral polio vaccine (OPV). Once associated with paralysis, deformity, and lengthy confinement in an “iron lung” ventilator, polio is now close to joining smallpox as only the second infectious human disease to ever be eradicated.
This entry unpacks the contemporary framing of polio as an urgent threat to global health security, before examining the ongoing multiform challenges that undermine efforts to eradicate the disease, and concludes by gesturing to the risks to global health that arise from a poorly implemented wind-down of polio investments as eradication draws seemingly nearer.
Pursuing Zero: Polio Eradication as a Security Project
The member states of the World Health Organization (WHO) first announced the ambitious goal of eradicating polio in 1988, framing this effort to reduce the worldwide incidence of the disease to zero by the year 2000 as a gift from the twentieth to the twenty-first centuries. Investment in eradication, the WHO noted, would strengthen health infrastructure and primary health care by delivering an eradication dividend to endemic countries. The Global Polio Eradication Initiative (GPEI), a public-private partnership launched in 1988, has played a pioneering role in coordinating the eradication activities of global health organizations and private philanthropies (notably the Bill & Melinda Gates Foundation and Rotary International). GPEI funding has made possible the deployment of vaccination teams across the world, financed the operation of 146 WHO-accredited surveillance laboratories, and supported the vital work of over 20 million social mobilizers worldwide in communicating the importance of vaccines to children and communities beyond the reach of other health services. GPEI has accomplished remarkable gains against the virus, spearheading the eradication of serotype 2 poliovirus in 1999 and serotype 3 in November 2012; serotype 1 remains endemic in only three countries (Afghanistan, Nigeria, and Pakistan), leading many commentators to speculate that eradication is within reach.
At the heart of GPEI’s eradication strategy is the annual immunization of at least 80% of children worldwide under 12 months of age. Immunization teams attempt to administer three doses of either IPV or OPV in the first 18 months of life to develop near-complete immunity in the child. If high coverage rates are not maintained, pockets of nonimmunized children develop, promoting the continued transmission of poliovirus. From such localized clusters, the virus has proven remarkably efficient at spreading across borders and between continents via infected travelers, displaced populations, or those who have refused or been denied immunization. In January 2013, for instance, poliovirus traced genetically to circulating strains common in Pakistan was identified as far away as Egypt, and later that year, an outbreak in Eastern Syria was also traced to the volatile Pakistan-Afghanistan border. Polio immunization as part of a broader eradication strategy is thus characteristic of other attempts to secure global health against infectious disease; it is based upon principles of prevention, surveillance, containment, and control.
This securitized approach to polio eradication has developed alongside broader shifts in global health policy that have prioritized disease-specific interventions, targeting progress toward clearly defined goals within ambitious time frames. Hardon and Blume (2005), for instance, have traced a general shift within global health policy from the broad-based, horizontal health projects of the early 1980s that were to be implemented through primary health-care systems – such as the WHO’s Expanded Programme on Immunization – to an emphasis on siloed, vertical disease eradication campaigns from the early 1990s. For donors such as Rotary International, which has raised more than US$1.7 billion for polio eradication worldwide as of 2017, time-bound and disease-specific campaigns help generate activism among members and provide a clear focus for fundraising. How, though, can global grand strategies and local priorities be reconciled when discordant priorities arise? Should endemic countries, often with multiple competing demands for limited health budgets, cooperate with the global push to eradicate the disease when few of their own citizens consider polio to be a key priority?
In the campaign to eradicate polio, these questions have largely been silenced in favor of a dogged determination to end the disease. There is an inclination, for instance, to concentrate on the virus – usually framed as an acultural entity – rather than on the distinctive social, political, and historical circumstances of the countries or regions where the virus circulates. Henderson (1998), for instance, highlights the affective power of the “siren song of eradication,” claiming that the public, donors, and global health personnel have been enticed by the finality of eradication, and neglect, as they did in the campaign to eradicate smallpox, the catalytic potential of strengthening local primary health systems as part of a broad-based eradication strategy. The GPEI campaigns have also been criticized for deploying a “cookie-cutter” model of global health intervention that assumes successful strategies from one context can simply be transplanted into significantly different geographical milieus. Rather than tailoring the conduct of interventions to the specific needs of regions with uneven health infrastructure or strained relations with central government, campaign staff tasked with delivering progress toward zero have deployed uniform and technical protocols that are poorly adapted to local needs and concerns.
Insecurity and Polio: Conflict, Misinformation, and Questions of Credibility
While GPEI has been fundamental in pushing the world closer toward zero cases of polio over the past three decades, 2014 represented a setback for eradication efforts worldwide, with a spike in cases from 93 in 2013 to 359 in 2014. This reversal in progress against the disease challenged the overarching narrative of the campaign against polio: that eradication was inevitable and would eventually be accomplished through more funding, greater coordination, and renewed political commitment. In May 2014, then Director-General of the WHO Dr. Margaret Chan attributed the downturn of eradication efforts to: “Armed conflict that flies in the face of international humanitarian law. Civil unrest. Migrant populations. Weak border controls. Poor routine immunization coverage. Bans on vaccination by militant groups. And the targeted killing of polio workers.” What is clear from the breadth of this statement is the sheer multiplicity of emergent political barriers to eradication, many of which originate from outside the polio campaign itself, which directly or indirectly continue to threaten global health security.
The clearest threat to polio-vulnerable populations is civil conflict, with the three remaining polio-endemic countries experiencing ongoing regional civil conflict in which the deliberate targeting of infrastructures for living has been commonplace. In these contexts, access to key populations is frequently limited due to violence and the contested control of territory. In Afghanistan, for instance, Taliban-controlled villages in the remote borderlands of Kandahar province have been inaccessible to polio vaccination teams for several years, and GPEI teams report that Afghan government commandos frequently raid and burn health facilities on the suspicion that they treat insurgents. In Nigeria, insurgents from the Boko Haram group hold vast swathes of territory in the northeast of the country and prevent vaccination teams from accessing local populations under their control. The success of vaccination is ultimately linked to the control of territory, with GPEI advocating greater coordination with government forces in conflict-affected areas in a move that critics see as raising greater suspicions among local communities about the supposed impartiality of public health teams. Perhaps best encapsulating the vulnerability caused by conflict is the 2015 return of polio after 19 years to Ukraine. Two children contracted polio in Western Ukraine at the external border of the European Union, but GPEI and the WHO were quick to blame the fragility of preventative health services in the country on the effects of the ongoing Russian-backed military intervention in the eastern Crimea and Donbass regions. The Ukrainian case acts as a reminder that even in seemingly conflict-free regions, the consequences of disruption to infrastructure and government inattention arising from conflict can be sources of magnified health insecurity.
Likewise, polio vaccinators and allied health workers have been deliberately targeted by warring parties and extremists because of their association with domestic and foreign security agendas. In Peshawar, for example, a restive city in the northwestern Pakistani province of Khyber Pakhtunkhwa, threats against door-to-door immunization staff made by armed groups, including the Pakistani Taliban, represent a real and present danger to the success of seasonal polio campaigns (Taylor 2016). These armed groups assert that the OPV campaign is actually a western conspiracy to sterilize Muslim children, and they see those who disseminate the vaccine as legitimate targets. Between January 2012 and July 2017, militants killed more than 100 people across Pakistan in drive-by shootings on primarily female polio workers and their security details. The deliberate targeting of door-to-door vaccinators has left many parents wary of having their children publicly immunized. During one immunization drive in September 2014, for example, over 16,000 children in the environs of Peshawar went unvaccinated because of parental fears about likely violence. Attacks against polio workers, then, pose a series of security challenges to routine immunization, the reputation of the Pakistani state in the eyes of donors, and the entire eradication initiative (Closser 2010).
Elsewhere, deliberate misinformation campaigns and rumors have stifled progress against the disease in the remaining endemic countries. Religious leaders and regional health authorities in three northern states of Nigeria encouraged parents to boycott polio immunization in 2003 and 2004. The boycott was motivated by concerns about the safety of the vaccine – including suggestions that the vaccine was contaminated with HIV, antifertility agents, and carcinogens – and skepticism about medicines arising from the deaths of 11 children in 1996 during Pfizer’s controversial trial of the trovafloxacin antibiotic in Kano. A Kano-based physician and leader of a prominent Sharia council in the state summarized the stance of those promoting the boycott when he stated that polio vaccines were “corrupted and tainted by evildoers from America and their Western allies … [w]e believe that modern-day Hitlers have deliberately adulterated the oral polio vaccines” (Jegede 2007). The boycott represented a huge setback for GPEI and the broader goal of global eradication. Case counts in the country rose from 202 in 2002 to 1143 in 2006, with virus surveillance suggesting that Nigerian strains of polio went on to spread to formerly polio-free countries in Africa and beyond. The urgent response to the boycott-linked outbreak is estimated to have cost GPEI over US$500 million. Renne (2010) suggests that the rumors and misinformation that birthed the boycott in northern Nigeria gained traction because of a variety of context-specific factors, most notably the interplay of socioeconomic marginalization; competing priorities of international, national, and regional campaigns; a long and also recent history of exploitative health practices; and contemporary insurgency. Of particular concern for the GPEI campaign was the vaccine skepticism espoused by influential, high-profile leaders; this highlights the role that individuals play in shaping the political, religious, and societal context for vaccine refusal. Contemporary campaigns seek to tackle insecurity arising from rumor at an early stage by prioritizing opportunities to listen to concerns voiced by prominent individuals, and those of the constituencies they represent, in order to better respond to local misinformation or anxieties before they develop into further national or regional crises (Taylor 2015).
In response to the situations described above, GPEI country plans in the remaining endemic countries have been adapted to include enhanced security components, new public health strategies, and more comprehensive communication plans. However, as Margaret Chan’s statement made clear, resistance and rejection of polio vaccination arise from multiple sources. In other words, any attempt to identify political limits to the accomplishment of polio eradication must also address broader, systemic issues within global health governance itself, particularly as and when these securitized policies compromise the credibility of operatives and messaging on the ground. There is perhaps no better illustration of the contradictions of global health intervention than the case of the ongoing civil war in Syria. United Nations mandates have imposed strict limitations on the operational ability of the WHO to provide even basic health interventions in conflict areas. Indeed, a growing chorus of voices on the ground in the country have accused the United Nations and the WHO of implicitly supporting the punitive counterinsurgency campaign of President Bashar al-Assad by disregarding the health needs of many Syrians living in rebel-held areas. Polio vaccination campaigns have been drawn into this controversy. Syria was first certified as polio-free in 1999, but local reports suggest cases of polio-like symptoms reappeared in May 2013 in the eastern Deir ez-Zour governorate. Syrian health officials only confirmed that the outbreak was linked to polio in October 2013, meaning that there were significant delays in the treatment of the disease and the containment of the virus. Kennedy and Michailidou (2017) note that the Assad government and the WHO in-country team were later accused of delaying the testing of stool samples from Deir ez-Zour and other areas sympathetic to the opposition, so as to perpetuate a health crisis that would weaken anti-regime resolve.
In closing, it is important to acknowledge a final set of security concerns that emerge around the polio eradication campaign, and these are questions about what happens after polio. The current push to accomplish zero cases of polio has, as noted above, diverted affective and financial investment streams toward eradication and away from equally pressing global health concerns such as the long-term viability of routine immunization systems. GPEI itself will end funding in non-endemic countries from 2019, and this means that many public health campaigns that have benefitted from the largesse of polio donors will see significant reductions in funding. If ending polio in the present has significant security implications, so too does the transition of global health programming away from secure polio investment streams.
The eradication of polio provides an opportunity to reorganize global health policy and practice, but if this opportunity is to be seized, global health actors must be cognizant of three principal barriers likely to restrict health gains after polio. These are weak and fragile immunization systems bequeathed uncertain futures after the withdrawal of polio funding, increased pressures on domestic financing as a result of polio donor withdrawal, and the operational complexities of shifting current approaches from vertical to horizontal health systems (i.e., from specifically targeted programs to general health services). GPEI partners cannot avoid the difficult political decisions that will emerge in these domains as a post-polio reality emerges, although the technical nature of many polio interventions acts to obscure the compounding impact that the wind-down of a key institutional assemblage could have on countries left to assimilate essential elements of donor-funded programs. Despite decades of eradication activity and several years of transition planning, for instance, much about the ownership of essential functions and routine immunization after polio is yet to be decided. The seemingly imminent eradication of polio thus represents a critical juncture to urgently rethink approaches to the transition of finance, assets, and human resources after polio that could further strengthen global health security and protect the lives and health of millions of children worldwide.
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