Help if you need it.
I’m working on the first draft of my Refutation Argument for your benefit.
The material I would ordinarily collect in my White Paper is posted below. As I massage that material into a draft Resolution, you’ll find my ongoing effort at the very bottom of this post in the section called: Draft Rebuttal.
Mine examines the primary claims of the hypothesis I defended in my Definition Argument, that because polio is fundamentally unlike smallpox—which was eradicated in the 1960s—the differences make it nearly impossible to eradicate polio, ever.
If it sounds ridiculous to devote 1000 words to the OPPOSITE of my own hypothesis, you’re misunderstanding a crucial element of good argument. To persuade skeptics to your point of view, you must address and refute the strongest counterarguments. Ignoring them is fatal. Readers will merely humor you if you try to skirt the best refutations and never change their minds.
- My post will be about 1000 words before the References section.
- It will use in-text citations WITHOUT parentheses.
- Please follow this model in your posts as well.
- It will use an APA-style References section
- APA is the new style choice of the Writing Arts Department
- I made mine for free using BibMe.com
- It will PRESENT but also REFUTE strong arguments against my hypothesis. It’s not AN OPPOSITION ARGUMENT, but a CONFIRMATION ARGUMENT that identifies objections to the hypothesis before re-affirming it.
- It’s a first draft, so it will embarrass me until I revise it.
- Once I revise it, it will be a second draft, still embarrassing but less so.
- Questions? Use the Reply field below this post.
I’ve gathered my sources, notes, quotations, and Purposeful Summaries here. Ordinarily, they’d be in my White Paper, and I will move them there after you’ve had a chance to see how much I gathered for my Rebuttal Argument. The actual Argument is at the bottom of the post, in the section called: Draft Rebuttal.
Full Text Link:
Journal of the Royal College of Physicians
eradication of disease: hype, hope and reality
The possibility of eradicating disease has been discussed for more than 100 years. A significant number of diseases have been targeted for eradication at various points, including hookworm (1907), yellow fever (1915), yaws (1954) and malaria (1955). So far, however, only one human disease, smallpox, has been eradicated,1 with rinderpest, a major disease of cattle, eradicated more recently.2 Both of these were viral infections that could be prevented with a highly effective, long-lasting vaccine. Polio and Guinea worm are now tantalisingly close to eradication, but polio eradication has been close to eradication for a decade and so shows how hard it is to achieve.
Eradication is highly attractive as a concept. The idea that one generation can, for all time, get rid of a disease for all successive generations is very motivating, including to people not usually involved in public health. Under some circumstances, eradication can be highly cost effective, because a time-limited surge in spend can save for all time, and this certainly was the case for smallpox.3 Even doing the preparation for an eradication campaign can stimulate innovation and change mindsets; the fact that malaria eradication is currently being considered has led to a systematic search for new tools and approaches.4
Three factors must be present. Easy diagnosis—so evident with smallpox—is not present with polio. Does this factor alone make eradication impossible?
Three factors have always been considered essential to any eradication effort. The first is effective interventions that alone or in combination can interrupt transmission of infection or at least take it well below R0 = 1 in all epidemiological settings. The second is that the disease has to be easy to diagnose, preferably with minimal complex laboratory facilities, so that the final cases at the end of eradication are identifiable. Smallpox, for example, could be diagnosed just by looking at someone, so finding the last cases was relatively easy and, indeed, schoolchildren were good case finders in the final stages.5 Finally, there must be no significant animal reservoir. A number of important infectious diseases that are now rare in humans, such as plague, will never be eradicated, because there is always a wild animal reservoir for the disease. In addition, for any eradication to be successful, we will need relatively simple-to-use technology, considerable central organisation, and sustained political will and money.
Should we be content with “good control,” or is the huge investment of resources necessary for eradication warranted?
It is possible to be highly ambitious in reducing the impact of a disease globally or eliminating it in a few defined areas without going for the final step of eradication, and this will be the right approach for the great majority of diseases.
Purposeful Summary: While successful eradication is hugely expensive (though not as expensive as the ongoing social cost of doing nothing to control a disease), attempting but failing to eradicate can be both costly and disastrous to the continuance of less ambitious efforts. Malaria was substantially reduced globally and eliminated locally during an effort to eradicate it. But because the stated goal was eradication, the campaign was considered a failure. Morale flagged as a result, funding for research dried up, and the disease rebounded.
Purposeful Summary: The risk of trying but failing to eradicate is greatest when the natural transference rate is high, as it is for polio. A single lingering case can start an epidemic.
Measles example: ” . . . in some high-risk groups, the incidence bounces back as soon as vaccine coverage drops, as has repeatedly been seen with polio. The recent mini-epidemics of measles in several communities in the UK where uptake of the measles, mumps and rubella (MMR) vaccine was low show how easily this can happen.”12
Eradication of polio could fail for several reasons:
- Insufficient technology
Shifts in antigens for vaccine targets
- Social and political factors
- Small group resistance to final severe controls
- Indifference of target groups as eradication nears
- (“Polio, which has been very close to eradication for more than a decade, suffered in part from imperfect organisation9 but more from social concerns from social and religious groups in Nigeria and Pakistan, who see no reason to collaborate on a disease they seldom now see.”)10
- Political will.
- “When the disease is very uncommon, the political advantage of investing a lot of resource into getting rid of the very final cases is low, as other public health problems become relatively more important to the population.”
To achieve eradication you need good technology, the maths must be right and, above all, the social, economic and political science for the endgame must be there before we start. Calling for eradication is easy, achieving it is not, and it will take a long time – always longer than planned and with most efforts in the ‘final mile’ when political support begins to evaporate. When eradication works, it leads to large investments producing indefinite gains. Trying and failing eradication is costly,17 pulls resources from other priorities, breeds cynicism and may destroy good control programmes. The key, therefore, is not to call for it where we cannot achieve it, and, for most diseases, we cannot. Once committed to a few sensible and achievable targets for eradication, determination, organisation, stoicism, deep pockets for a very long haul, innovation and flexibility are essential.
An editorial from Eastern Mediterranean Health Journal 2016
Closer to a polio-free Eastern Mediterranean Region
A. Alwan and C. Maher
Things were looking very good in 2012 before the “final stage” of eradication was interrupted by social factors.
By the end of 2012, when only 95 cases were reported in total from the Region, it seemed that finally stopping the transmission of poliovirus was just around the corner. The number of cases and countries were at the lowest-ever recorded levels
Purposeful Summary: Despite social and political setbacks, in 2012, 2013, and 2014, rapid and effective responses have brought several outbreaks under control in Nigeria, Pakistan, and Afghanistan. Constant conflict in Afghanistan, bans on inoculation in some regions, attacks on inoculators in Pakistan, complicated eradication efforts and reversed successes. A virus imported from Nigeria caused an outbreak in Somalia. Etc.
Coupled with a massive surge in partner agency technical support – WHO alone has more than doubled the size of the teams working on polio in the two countries since the start of 2014, and now has nearly 2500 technical and operational experts in the field – these improvements have had a significant operational impact. At the time of writing, only 30 cases of polio have been recorded by Pakistan (18 cases) and Afghanistan (12 cases) combined so far in 2016 – a far cry from the 334 cases recorded by these countries in 2014 (9). Similarly, in 2016 only about one in 10 environmental samples in Pakistan has been positive for wild poliovirus, compared to one in every two in 2014.
The author is optimistic in 2016. Let’s see whether his optimism was warranted.
Polio Vaccine and Gresham’s Law
Letter to the Editor of Indian Journal of Pediatrics 2004
Of questionable value, but the article does provide the useful term “donor fatigue” to explain the drying up of resources that may be accompanying the final stage of eradication. Also of interest, the worry that the IPV vaccine will drive OPV from the market, leading to scarcity of a commodity needed to inoculate millions who could in no way afford the more expensive alternative.
The USA schedule including inactivated polio vaccine (IPV) costs a prohibitive $11 million per case of vaccine associated paralytic polio prevented (VAPP). 2 It was
hoped that after global eradication this may be discontinued. Post 9/11, with the threat of bio-terrorism, vaccine discontinuation is not priority. Perhaps by coincidence, ‘donor fatigue’ began to set into the global polio eradication programme. The government of India is now left picking up the tab of Rs 400 crores per year. Then suddenly Gresham’s Law manifests itself. Gresham’s law states that the bad drives out the good, and that bad money drives good money out of circulation. In the context of vaccines, the equivalent law will state that if there is a more expensive vaccine along side a cheaper vaccine (good coin of Gresham) the cheaper version will disappear from the market. (Like how the Typhoid A & B and Cholera vaccine [TABC vaccine] inexplicably disappeared, once a more expensive typhoid vaccine arrived on the scene). The government of India is in a quandary. It had given up its capacity to manufacture oral polio vaccine indigenously, on advise from overseas. 4 User-fee will have to be introduced for IPV. The indigent will remain unvaccinated. It is then, that the big surge of polio will sweep across the country, among the unvaccinated.
Endgame for polio eradication?
Overcoming social and political factors
Google Scholar Link:
This will likely be the primary focus of my argument: the intransigence of “local actors” whose resistance to force, suspicion of foreign agents, and vulnerability to indoctrination make universal cooperation impossible.
Abstract: We examine the social and political factors that are barriers to polio eradication. Options are discussed for solving the current impasse of polio eradication: using force, respecting individual freedoms and gaining support from those vulnerable to fundamentalist ‘propaganda’. The travails of the GPEI indicate the need for expanding the Convention on the Rights of the Child to address situations of war and civic strife. Such a cultural and structural reference will provide the basis for global stakeholders to engage belligerent local actors whose local political conflicts are barriers to the eradication of polio. Disregard for these actors will result in stagnation of polio eradication policy, delaying eradication beyond 2018.
Contains a very nice summary of historical polio policies and successes:
Polio has no known cure but can be prevented by vaccination. Before Jonas Salk invented the polio vaccine in 1955, polio paralysed and killed up to 500,000 people annually worldwide (CCP, 2013). Salk’s inactivated polio vaccine (IPV) reduced polio transmission in the USA from 20,000 cases per year in the 1950s to around 1000 cases by the 1960s (CCP, 2013). In 1961, oral polio vaccine (OPV) was invented by Albert Sabin, and from 1963, the USA replaced IPV with OPV in mass polio vaccination campaigns (CCP, 2013; Gautam, 2005). After the Centers for Disease Control and Prevention (CDC) concluded that the transmission of polio had ended in the USA in 1979, Rotary International committed to provide vaccines to six million children in the Philippines (GPEI, 2014). Due to this successful campaign and followed by campaigns in other countries, Rotary collaborated with Albert Sabin on a plan to vaccinate all children against polio worldwide utilising Sabin’s OPV. The Rotary PolioPlus programme was launched in 1985. In 1988, the Global Polio Eradication Initiative (GPEI) was launched with the goal of eradicating polio by the year 2000. When this goal was not achieved, a five-year extension was enacted. Polio worldwide has decreased from an estimated 350,000 cases in 1988 to just 416 cases in 2013 (CDC, 2014b; GPEI, 2014). However, without complete eradication, polio continues to plague populations and to burden the public health system of all infected countries.
We Can’t Give Up Now: Global Health Optimism and Polio Eradication in Pakistan
Google Scholar Link:
Full Text Link at Rowan Campbell Library:
The Polio Eradication Initiative, the largest coordinated public health project in history, is currently facing serious difficulties. For years, it has tried and failed to eliminate polio from its last strongholds in Afghanistan, Pakistan, and Nigeria. Drawing on document analysis as well as participant observation and interviews in Pakistan, Atlanta, Geneva, and Montreal, I explore how officials in the Polio Eradication Initiative systematically devalued or quieted evidence that eradication was not achievable and emphasized evidence that it was achievable, thus creating a string of optimistic projections. Polio eradication’s culture of optimism ensures the continuation of the project by convincing donors and officials alike that eradication is immanent. At the same time, it prevents open, objective analysis of the problems the project faces.
Eradication, the permanent obliteration of a disease, is a powerful ideal. World Health Organization (WHO) Director-General Margaret Chan has called it “the ultimate contribution for sustainable health development” and it attracts high-profile supporters such as Bill and Melinda Gates (Gates and Gates 2007). Yet eradication programs have a high risk of failure and a high degree of difficulty. In the twentieth century, seven major eradication programs were attempted—against hookworm, yellow fever, yaws, malaria, smallpox, polio, and guinea worm—but only the Smallpox Eradication Program succeeded.
While the program has made enormous progress, bringing the worldwide polio case count down from hundreds of thousands of cases a year to around a thousand, completing the task in difficult and intractable areas has proved elusive, despite funding of nearly US $1 billion per year (WHO 2010b).
Here, I explore the ways in which officials in the Polio Eradication Initiative systematically devalued or quieted evidence that eradication was not achievable, while they emphasized evidence that it was achievable, so creating a string of optimistic projections.
Part of the reason for optimism in polio eradication, I will argue, is strategic. Because eradication is so high-risk, its proponents must defend their project against those who argue that limited funding would be better spent elsewhere.
The culture of optimism makes polio eradication more difficult by preventing open, objective analysis of the problems the project faces.
The article focuses on the difficulties of achieving end-stage eradication efforts in Pakistan:
Eradicating polio from Pakistan is extraordinarily difficult for several reasons. Fecal-oral transmission of poliovirus is very efficient in Pakistan’s hot climate, high population density, and poor water and sanitation infrastructure. In addition, the per-dose efficacy of oral polio vaccine (OPV) in South Asia is low—children may need to be vaccinated 10 or more times to ensure immunity, with at least a month between each dose (Grassly et al. ). Political and organizational issues also present major challenges (Closser 2010). Pakistan is being pulled apart by power struggles between the army, political parties, lawyers’ associations, the United States, and the Taliban, and polio eradication is not a political priority. Natural disasters—a major earthquake in 2005, flooding in 2010—further diverted political attention from polio. Eradication is not a priority for the Pakistani populace, either: polio is ranked thirty-fourth in one analysis of causes of healthy years lost in the country (Hyder and Morrow 2000), and it is not a disease that concerns mothers greatly. 3
But throughout the Polio Eradication Initiative’s 20-year lifespan, these issues have been minimized or disregarded entirely by international officials. Instead, a consistently optimistic stream of rhetoric and planning has proceeded as if these difficulties did not exist. . . . For the past 10 years, Pakistan has done door-to-door campaigns multiple times a year (an endeavor well beyond what was outlined in 1993), yet polio transmission continues.
The Border Crossing Problem
But in 2006, there were still pockets of ongoing virus circulation along the border of Pakistan and Afghanistan, and surveillance data showed that viruses on both sides of the border were genetically closely related (WHO 2007b). The border is a particularly difficult area because infrastructure is nearly nonexistent in many places, nomads and refugees move freely across the international boundary, and United Nations security regulations mean that oversight by WHO or UNICEF employees is all but impossible.
The Problem of Switching from Trivalent Vaccine to Monovalent Type 1 Vaccine:
However, the introduction of mOPV1 in Pakistan did not have quite the effect that was hoped. By the end of 2006, 40 cases of paralytic polio (Type 1 and Type 3) were found in Pakistan, up from 28 in 2005 (see Figure 3). The use of mOPV1 was associated with a reduction in the number of Type 1 cases, to 20 in 2006 compared to 27 in 2005. The unintended side effect of the use of mOPV1 in Pakistan, however, was a resurgence of Type 3 poliovirus: 20 cases of paralytic Type 3 polio in 2006, up from only 1 in 2005.
Growing Donor Skepticism
A few remain staunchly committed to the project: Bill Gates, in a recent video (2011), called polio eradication his “top priority,” despite reports that he harbors some concerns (Guth 2010). But some have quietly begun shifting funds to other projects. Others say that they “have not lost faith yet” but view the Polio Eradication Initiative’s projections with an increasingly skeptical eye.
A representative of another bilateral donor agency told me that they were concerned about very low routine immunization coverage in Pakistan. “One reason may be—polio,” he said, noting that time spent organizing and carrying out polio vaccination campaigns was time not spent on other health issues.
Polio Eradication: Strengthening The Weakest Links
Full Article Link:
Polio eradication, like all eradication efforts, is a gamble. If it fails, much of the money spent will have been wasted. If it succeeds, the world will reap a dividend. Success or failure and the magnitude of the dividend depend on a long chain of “weakest links.” In this paper I identify these links and explain how the chain can be strengthened. A crucial vulnerability is the current plan to halt vaccination using the live-attenuated oral polio vaccine in the post-eradication era. This weakest link can be strengthened by efforts that lower the cost to poor countries of vaccinating with the inactivated poliovirus vaccine.
The point of this article is not to identify a range of difficulties in eradicating polio but instead to recommend one solution that may overbalance lingering difficulties. However, in its background section, it does in fact summarize the weak links.
Since the global polio eradication initiative was launched in 1988, the number of polio cases worldwide has declined more than 99 percent. This is a remarkable achievement in terms of control, but it falls one percentage point short of eradication. Eradication requires, as a first step, that incidence equal zero—exactly.
Why eradicate? The reason is not only to prevent illness. It is also to avoid the need to vaccinate in the future—the savings from which is sometimes called the “eradication dividend.” The dividend from smallpox eradication was huge. For polio the dividend is likely to be smaller, but it will be positive provided the chances of success are large enough and the risks of stopping vaccination post-eradication are low enough. 2
Eradication is a high-stakes gamble. Indeed, it is important not to be misled by the success of the smallpox eradication campaign, for that effort barely succeeded; also, the ongoing effort to eradicate Guinea worm has stumbled for even longer than that for polio, despite being a much easier target. 3
Eradication succeeds or fails depending on the “weakest links” within each specific component of the eradication effort. For polio, success depends on eliminating the wild viruses from the remaining four endemic countries, while ensuring that transmission continues to be interrupted everywhere else. Every endemic country and every other country that fails to sustain a critical level of population immunity is a weakest link in this section of the chain. Should we succeed in this phase, however, we will then need to confront a new set of challenges and many additional weakest links. These post-eradication challenges must be considered today, because if countries expect that any of these weakest links will fail, support for the current phase will fall away. Plans for the future must be integrated with current planning.
Weak Link: Afghanistan/Pakistan
People move back and forth across the porous border separating Afghanistan and Pakistan, both sides of which are variously ungoverned or under the control of antigovernment, Taliban, Al Qaeda, or tribal groups. To initiate a vaccination campaign in this conflict zone requires a cease-fire, but getting one hinges on the consent of every warring party. Making matters worse, polio can persist in, and spread from, even small populations, and not all groups are friendly to the polio eradication effort. After being warned by religious leaders that polio vaccination “was an American plot to sterilize innocent Muslim children,” many parents refused to vaccinate their children.4 Doctors associated with the polio eradication effort have been killed—targets of roadside bombs and suicide attacks. 5
Weak Link: Kano, Nigeria
The most important single event in the history of the global polio eradication effort was the suspension of vaccination in northern Nigeria, especially Kano State, in late 2003. The suspension was urged by political and religious leaders claiming that “the vaccine could be contaminated with anti-fertility agents…, HIV, and cancerous agents.” 6
To some people living in northern Nigeria, polio eradication seems a misdirected priority. Why should they be urged to vaccinate their children for polio, and be given the vaccine for free, when their children are dying of other diseases, for which no help is being offered? 7 To address this concern, Nigerian health authorities adopted new tools and tactics in early 2006, replacing national immunization days with “immunization-plus days,” during which “a range of childhood vaccinations and other health interventions are offered along with the oral poliovirus vaccine.” 8Immunization improved in some places, but not everywhere. Population immunity remains dangerously low in Kano.
Weak Link: Uttar Pradesh and Bihar, India
The GPEI has also tried to improve the efficacy of the vaccines it is able to administer, by replacing the normal, trivalent oral poliovirus vaccine, which protects against all three types of polio, with monovalent versions, which are more effective at immunizing for individual types. 9
The monovalent vaccines are crucial to the eradication effort in Uttar Pradesh and Bihar, two northern states of India characterized by rapid population growth, high population density, and poor sanitation—ideal conditions for spread. Here, coverage with multiple doses of trivalent vaccine has been high, but the vaccine often fails to stimulate immunity, probably because of the high prevalence of other enteroviruses and diarrhea. According to one study, the efficacy of trivalent oral vaccine in stimulating immunity to types 1 and 3 polio is just 9 percent in Uttar Pradesh. 10 Ordinarily, four or five doses of live oral vaccine should be sufficient to guarantee immunity, but in northern India some children have been paralyzed by polio after receiving ten or more doses. The use of monovalent oral vaccine will help, but the protective efficacy of the type 1 vaccine in Uttar Pradesh is just 30 percent. 11 To boost immunity even more, the GPEI is now considering additional options, including the introduction of bivalent vaccines (to offer protection in areas with both types 1 and 3 polio) and the inactivated (or killed) polio vaccine.
Weak Link: War Zones
Polio has circulated uninterrupted for more than a year in several formerly polio-free countries, including Sudan, Chad, the Democratic Republic of Congo, Angola, and Niger.
Weak Link: Obtaining the Financing
So far, the GPEI has raised more than $6 billion from international sources. This is much greater than the amount raised to eradicate smallpox, but it is not enough. More than $2 billion of additional money will be needed through 2013 (of this total, some money has already been pledged; a gap of about $870 million remains). 12
The willingness to pay for eradication depends on donors’ believing that the effort will succeed. After the Nigerian boycott, donations by the European Union stopped. 13 It was only after vaccination resumed in Nigeria that the money flowed once again. If donors believe that eradication will fail, funding will dry up; then the donors’ expectations will be self-fulfilling.
Weak Link: Weakened live viruses are used in the vast majority of inoculations because they are vastly cheaper and because they can be administered without needles by volunteers who are not doctors. Those live viruses mutate as they spread, and they could in themselves become increasingly dangerous, so even after the eradication of wild virus, the most vulnerable nations will still need to continue to inoculate.
When smallpox was declared eradicated, countries could decide independently whether or not to stop vaccinating. For polio, this approach could prove disastrous. This is because the weakened live virus strains in oral vaccine can evolve to reacquire the ability to cause paralytic disease and to spread. Outbreaks of circulating vaccine-derived polioviruses have occurred before (since 2000 in the Dominican Republic/Haiti, the Philippines, China, Madagascar, Indonesia, Cambodia, Niger, Burma/Myanmar, Nigeria, Ethiopia, and the Democratic Republic of Congo); more are virtually inevitable. Unless steps are taken to limit such outbreaks, and to extinguish those that cannot be prevented, the gains to eradicating wild polio will shrink. Indeed, if the vaccine-derived viruses evolve to resemble the wild viruses, as many virologists believe is likely, and if these strains cannot be eradicated, then the gains from interrupting wild polio transmission will be lost; the entire effort will only have succeeded in replacing one set of viruses with another. 15 The risk is real. Although wild type 2 polio was eradicated long ago, type 2 vaccine–derived polioviruses have circulated in Nigeria for years.
Weak Link: Odds of an outbreak of “vaccine-derived” polio following the eradication of wild poliovirus?
How likely is it that new vaccine-derived virus outbreaks will occur after the wild polioviruses have been eradicated? According to one modeling study, there is a 65–90 percent chance that at least one outbreak will occur within a year of coordinated cessation of vaccination. After that, the annual probability is expected to decline. By the third year the probability may be only 1–5 percent. 16 Note, however, that the impact of such an outbreak will increase over time. The longer the live oral vaccine continues not to be used (and inactivated polio vaccine not used in its place), the greater will be the pool of susceptible people in the population. The risk of a vaccine-derived virus outbreak could rise even as the probability of an outbreak declines.
16. Follow link provided above to its source:
- 16 See R.B. Aylward , R.W. Sutter, and D.L. Heymann, “OPV Cessation—The Final Step to a ‘Polio-Free’ World,” Science310 , no. 5748 ( 2006 ): 625 –626 Crossref, Medline ; and R.J. Tebbens et al., “Risks of Paralytic Disease Due to Wild or Vaccine-Derived Poliovirus after Eradication,“ Risk Analysis 26 , no. 6 ( 2006 ): 1471 –1505. Crossref, Medline
Other Weak Links:
- The need to synchronize OPV cessation worldwide
- Vulnerability of Immuno-suppressed recipients
- Proliferation of IPV production facilities worldwide
- Escaped Lab Samples
- Surveillance Difficulties
- For polio, surveillance is particularly difficult. Symptoms only show in about one in 200 infected people. Moreover, “acute flaccid paralysis” has other causes than polio. Evidence of polio circulation cannot be proved in the field; it must be confirmed by clinical diagnosis.
- The Shame Factor
- Surveillance is of value only if the information obtained is reported to the world. National pride can be a barrier to rapid reporting. Officials in Somalia suppressed information about smallpox cases in the final months of that eradication campaign, not wanting their country to bear the stigma of being the last to harbor the virus.
- Outbreak Preparedness and Response
- Delicate Post-Eradication Strategy
Substituting Live Vaccine
If poor countries could acquire inactivated vaccine more cheaply, this and other post-eradication weakest links would fall away.
The likelihood of a post-eradication outbreak of vaccine-derived viruses would be unchanged, but the consequences of such an outbreak would be less dire. Post-eradication outbreak preparedness and response would also improve.
The incremental cost to all poor countries of switching from live oral to inactivated vaccine is about $317 million per year.27 This is less than the amount spent each year on polio eradication since 2000; it is less than half as much as has been spent in recent years. 28
Rich countries might be willing to pay for this cost, at least for a period of time (say, five years). Recall that the probability of a post-eradication outbreak of vaccine-derived virus will decline over time. If the risks of such outbreaks can be greatly reduced, then the risk-reward balance will tilt in favor of vaccine cessation, for both poor and rich countries. This would yield the world a return on its eradication investment.
Reducing the Cost of Inactivated Vaccine (IPV)
Reductions in the cost of stimulating population immunity using inactivated polio vaccine would help even more. Shifting production to developing countries could lower production costs,
Another idea is to spread the fixed costs of needle injection by combining inactivated poliovirus with other antigens.
Alternatively, use of intradermal injection would allow inactivated vaccine to be administered with almost as much ease as oral vaccine.
The GPEI is exploring all of these possibilities. Although the world’s attention today is understandably focused on eradicating the wild viruses, the ultimate success of the initiative will depend as much on the steps being taken now to improve the economics of inactivated polio vaccination. These steps will strengthen what is perhaps the most critical weakest link in the post-eradication chain.
National choices related to inactivated poliovirus vaccine, innovation and the endgame of global polio eradication
Kimberly M. Thompson, 2014
Google Scholar Link:
Rowan Library ProQuest Link:
From the Abstract, a plan to replace Oral Vaccination with IPV (Inactivated Polio Virus) inoculation, which requires needles.
Based on insights from modeling, we offer some perspective on the current status of plans and opportunities to achieve and maintain a world free of wild polioviruses and to successfully implement oral poliovirus vaccine cessation. IPV costs and potential wastage will represent an important consideration for national policy makers. Innovations may reduce future IPV costs, but the world urgently needs lower-cost IPV options.
The continuing problem of persistent endemic pockets that can trigger outbreaks in places that do not maintain high immunization percentages:
However, the last reservoirs of WPV1 in the remaining endemic areas of a few countries continue to experience cases and to export viruses that cause outbreaks (defined as one or more linked paralytic cases) in previously-polio free areas that achieved, but failed to maintain, high population immunity.
Thus, after reaching its lowest ever annual global number of countries reporting WPV cases and total reported WPV cases to date in 2012 , importations of WPV1 into countries with insufficient population immunity to prevent transmission (e.g., Somalia, Kenya and Syria) led to outbreaks in 2013 .
The Art of Eradicating Polio
Google Scholar Link:
Full Text Online Link:
The article made this claim in 2013, in a bold headline:
The world is close to wiping out the poliovirus, but Nigeria threatens to undo it all. Muhammad Ali Pate is on a mission to change that.
Anecdote of Muhammad Ali Pate, Nigeria’s Minister of State for Health, convincing one reluctant boy to permit his family to be vaccinated.
It’s a small victory, he confides later in the back seat of the Land Cruiser. But that’s what it takes to eradicate polio in Nigeria. “There is science to polio eradication,” he says. “But making it happen is art.”
Muhammad Ali Pate has been trying to do what no one has been able to accomplish before him—finally drive the poliovirus from Nigeria, one of the last and most stubborn reservoirs in the world. The stakes are high: The outcome of the 25-year-and-counting effort to wipe the virus off the face of the earth rests in large part on the effort that Pate and his handpicked team have put together here in northern Nigeria.
You can’t do it by fiat, Pate explains to me later during a 3-day car trip in mid-April through the north, where the virus is entrenched. Top down doesn’t work in a country as complicated as Nigeria, an amalgam of colliding cultures and ethnic groups, with a discredited and powerless federal government and relentless insurgency and violence.
Pate is convinced that the virus can be dispatched from the country by the end of 2014, the new deadline set by the leaders of the Global Polio Eradication Initiative (GPEI), which has so far spent more than $10 billion trying to eliminate the scourge of polio worldwide. More data, more money, and more troops are being poured into the effort than ever before, thanks to the Bill & Melinda Gates Foundation and other international partners and donors, who desperately want Nigeria to finish the job so the rest of the world can, too. And they have been betting big bucks that Pate, if anyone, can pull it off. He has come close before, getting cases down to a record low of 21 in 2010.
The Human Development Index ranks Nigeria 153rd out of 187 countries; Transparency International places it among the more corrupt countries in the world. Understandably, there is no love lost between the poor of the North and the government they feel has abandoned them.
So when vaccination teams come around with nothing to offer but drops of oral polio vaccine (OPV), many people are suspicious and fall prey to rumors that the vaccine is contaminated with the AIDS virus or infertility drugs, part of a Western plot to decimate the Muslim population. Rumors and misinformation reached such a frenzy in 2003 and 2004 that four northern states banned all polio vaccination outright, sending cases soaring to 1122 by 2006.
We are going to Kaduna and Katsina states, which last year had about 40% of the polio cases in the country and where, despite the country’s stepped-up effort, vaccinators are still missing too many kids. As we set out, Pate talks about the murders in Kano, another of the high-risk states. At about 9 a.m. on 8 February, gunmen on motorcycles stormed two clinics in rapid succession, killing 10 health workers and one client, all women. The vaccinators had just assembled before heading out for their “mop-up” day, when they try to find and vaccinate kids missed during the previous 3-day door-to-door campaign.
Violence and terrorism in Nigeria are nothing new. The Islamist insurgency is so intense that the president in May declared a state of emergency in three northern states and sent in troops. Schools have been burned, students murdered, villagers massacred. Aid workers have not been immune. In August 2011, 23 were killed and scores injured when the Islamist insurgent group Boko Haram bombed U.N. headquarters in Abuja. But polio workers had never before been directly targeted. No one has claimed responsibility.
Haruna Kaita, a professor of pharmacy at Ahmadu Bello University in Zaria spread rumors about the polio vaccine.[He] analyzed samples of OPV and found traces of estradiol and other contaminants, feeding into the furor that led to the vaccination ban of 2003 and 2004.
The ban was lifted only after intense national and international lobbying, with then-President Olusegun Obasanjo assembling several delegations to test the vaccine, and GPEI providing assurances that only vaccine made in Indonesia, a Muslim country, would be used in Nigeria.
Kaita made a CD repeating earlier assertions that the polio vaccine “contain[s] birth control and birth defect-causing substances … [and] that children could contract other diseases through the [vaccine], it could be cancer, HIV, or mad cow disease …” The cleric, Ibrahim Ahmad Aliyu, said, according to a translation: “Forceful oral polio vaccinations are an American-planned genocide against the Muslim populations in Nigeria.”
Anecdote of an outbreak that spreads from Nigeria throughout the Horn of Africa among the unvaccinated hordes displaced by the ongoing refugee crisis from Somalia.
Always in the News
As I write this, NPR is broadcasting a story of vaccination workers being killed by “militants” in Pakistan. They link the episode to “the CIA used vaccinators to spy on Pakistanis in an effort to find Osama bin Laden.”
The eradication of smallpox from planet Earth in 1980 by a worldwide immunization campaign raised unrealistic hopes that other diseases could be similarly vanquished. The exuberance of health professionals who set their sights immediately on polio, malaria, and cholera was understandable, but dangerous. If polio were identical to smallpox, the same techniques might suffice to eradicate it next. But if polio is fundamentally different, then the argument from analogy to smallpox fails, and efforts to eradicate polio, based on the argument that “it’s been done before,” could more than just fail; they could backfire catastrophically. The cost of the attempt is enormous, and the risk of failure is very high, so let’s examine the similarities between smallpox and polio and see if they augur success.
Several factors are considered essential to any eradication effort. Christopher Whitty, professor of public and international health at the London School of Hygiene and Tropical Medicine, identifies three. Others may count differently, but if polio and smallpox are sufficiently different in any category essential to eradication to void the comparison, the “did it before” argument will fail. In his Millroy Lecture “Eradication of Disease: Hype, Hope, Reality,” he names as the first pre-requisite: “effective interventions that alone or in combination can interrupt transmission of infection or at least take it well below R0 = 1 in all epidemiological settings.”
As Whitty explains it, R0 = 1 represents the situation where one infected person passes on the disease to just one other person who in turn does the same so that the disease stays stable in the population. At a minimum, then, interventions must exist that can prevent rapid spreading during an outbreak. In the best case, when the R0 can be forced below 1, local elimination and potential eradication can be achieved. For much of the world, local elimination has already been accomplished. In all but a few countries, no new cases of polio have been detected in decades. As described by Ganapathiraju, Morssink, and Plumb in “Endgame for Polio Eradication?“:
in 1955, polio paralysed and killed up to 500,000 people annually worldwide. Salk’s inactivated polio vaccine (IPV) reduced polio transmission in the USA from 20,000 cases per year in the 1950s to around 1000 cases by the 1960s. [Since then,] polio worldwide has decreased from an estimated 350,000 cases in 1988 to just 416 cases in 2013.
Such remarkable success—a 99.9% reduction in diagnosed cases in 30 years!—continues to encourage eradication advocates, including the Bill Gates Foundation, the World Health Organization, and the Global Polio Eradication Initiative (GPEI) that total triumph is inevitable, if not imminent. In fact, seemingly every year, when it solicits funding for its continuing effort, the GPEI announces a “game-changing” or “breakthrough” technology that will once and for all achieve the ultimate victory.
But that victory has so far proved elusive, perhaps because of fundamental differences between smallpox and polio. Again according to Whitty, to be eradicable, “the disease has to be easy to diagnose, preferably with minimal complex laboratory facilities.” But whereas schoolchildren were able to detect the last cases of smallpox among their classmates by casual external observations alone, they would be no help detecting polio, which can persist completely unnoticed in human hosts for decades without causing symptoms.
Fortunately for polio eradication advocates, Whitty’s third essential factor presents no challenge. Polio exists either in human hosts or not at all. There is no significant “wild animal reservoir” for the disease to harbor in between human hosts. But the final ironic difference between the smallpox and polio viruses is that polio uses humans as a sort of “animal reservoir,” and while it persists in unwitting human hosts, often subjected to repeated rounds of immunization efforts, it mutates, emerging as something no longer “wild,” but transformed into a “vaccine-derived virus.”
This last and perhaps most significant difference between smallpox and polio may be the distinction that finally tips public sentiment against spending staggeringly large sums to eliminate a disease that presently afflicts so few. As reported in “The Art of Eradicating Polio” by Leslie Roberts, a Nigerian boy recently voiced the bewilderment of his country in a conversation with Muhammad Ali Pate, Nigeria’s Minister of State for Health. “Why do they bring only polio vaccine when we get no help with all our other problems? And are you going to force us to take it?” he asked. His question illustrates a reluctance that is increasingly difficult to surmount among populations whose children die by the thousands from diarrhea.
The longer the final stage of eradication drags on the more challenges it faces. Despite impressive successes, and there have been many, setbacks seem maddeningly inevitable. Alwan and Maher report, in 2016, in “Closer to a Polio-Free Eastern Mediterranean Region” that
WHO alone has more than doubled the size of the teams working on polio in the two countries since the start of 2014, and now has nearly 2500 technical and operational experts in the field . . . only 30 cases of polio have been recorded by Pakistan (18 cases) and Afghanistan (12 cases) combined so far in 2016 – a far cry from the 334 cases recorded by these countries in 2014.
Yet, according to Svea Closser’s “We Can’t Give Up Now: Global Health Optimism,” after worldwide spending of nearly $1 billion again in 2016, the fight did not end. Neither did another billion accomplish the goal in 2017. One must ask, as many governments, private foundations, public health professionals, and that Nigerian boy already have, “How much longer can we justify spending so much of our scarce resources on a disease that most of the world has not seen in decades?”
Even success, if it’s achieved, might not be success. As Closser warns us, “When smallpox was declared eradicated, countries could decide independently whether or not to stop vaccinating. For polio, this approach could prove disastrous.” The cheaper OPV vaccines are a double-edged sword. They are favored for mass inoculations and millions of doses are delivered every year, preventing countless cases of polio. But they deploy “weakened live virus strains” that can “evolve to reacquire the ability to cause paralytic disease and to spread. Outbreaks of circulating vaccine-derived polioviruses have occurred before [in 11 countries since 2000]; more are virtually inevitable.”
It’s even possible that vaccine-derived viruses could evolve to mimic the three “wild” polio viruses we’ve taken such pains to eradicate. If that happens, according to Closser, “the gains from interrupting wild polio transmission will be lost; the entire effort will only have succeeded in replacing one set of viruses with another.”
Alwan, A., & Maher, C. (2016). Closer to a polio-free Eastern Mediterranean Region. Eastern Mediterranean Health Journal, 22(9), 645-646. doi:10.26719/2016.22.9.645
Closser, S. (2012). We Can’t Give Up Now. Medical Anthropology, 31(5).
Ganapathiraju, P. V., Morssink, C. B., & Plumb, J. (2015). Endgame for polio eradication? Options for overcoming social and political factors in the progress to eradicating polio. Global Public Health, 10(4), 463-473. doi:10.1080/17441692.2014.994655
Roberts, L. (2013, October). The art of eradicating polio. Science, 342(6154).
Whitty, C. J. (2014, August 01). Milroy Lecture: Eradication of Disease: Hype, Hope and Reality. Retrieved March 18, 2018, from http://www.clinmed.rcpjournal.org/content/14/4/419.full