The Polio Epidemic in Nigeria: A Public Health Emergency

By

Chidi Chike Achebe MD, MPH

cachebe@hsph.harvard.edu

Polio is a contagious and potentially debilitating disease that usually infects young children. In its most severe form, the disease attacks the nervous system causing paralysis, muscular atrophy, deformation and sometimes death.[i] It is caused by the Poliovirus, an Enterovirus that occurs naturally only in humans. In the developing world, the Poliovirus is often spread by the ingestion of food or drinking water contaminated by the virus. The virus may also be contracted through direct contact with infected stool or throat secretions.[ii] 

According to the World Health Organization, “ Africa is on the brink of the biggest polio epidemic in years, with the crippling disease hitting Nigeria hard and re-emerging in Sudan 's war-ravaged Darfur region”[iii].

World wide, the number of Polio cases has reached 339 so far this year, almost double the number for the same period last year. What this means is that the incidence of Polio cases this year is on a trajectory to exceed the 784 recorded in the past 12 months! ‘Only six countries worldwide - Afghanistan , Egypt , India , Niger , Nigeria , and Pakistan - are considered polio-endemic. Of these nations, about 99 percent of all new polio cases in the world have been detected in Nigeria , Pakistan and India .’[iv]

Nigeria accounts for 77% of cases of polio in the world, with 259 confirmed cases of the wild polio virus across the country. Kano State in northern Nigeria is at the epicenter of the world's fastest growing polio outbreak in recent memory![v] To place this in frightening, vivid context: The Nigerian cases account for nearly 50 percent of 784 cases reported in a total of 15 countries in 2003, and without immediate control, could potentially lead to a world wide pandemic involving scores of millions of people!.[vi]

 Last month, in a move that delighted most medical observers the world over, the government of the northern Nigerian state of Kano confirmed to the World Health Organization (WHO), that it would resume in early July, the polio vaccination campaign that it had abandoned 8 months earlier. Concerns voiced by influential elders in that state that the Polio vaccines supplied by Western health organizations could be tainted with infertility drugs and serve as a source for the spread of HIV were widely believed to have been a major driving force for the abandonment of the immunization campaign. Since October, three other northern Nigerian states banned door-to-door vaccinations until officials there were satisfied that the vaccines did not contain harmful substances. Sadly, UN officials now say a third of the world's cases this year may well have come about as a result of this vaccine boycott.

Figure 1: Map of Nigeria showing distribution of W3 and W1 strains of the Polio virus (W=wild). The clustering of cases occurs in Kano and Jigawa as well as surrounding northern states by extension. Cases have been reported as far south as Lagos State . Courtesy of the WHO.

The potential to spread like a wild Fire

The decision to resume wide spread immunizations in Kano state could not have been more timely or critical. According to UN reports, the polio outbreak has now spread from Nigeria to neighboring countries, placing 15 million children at risk and undermining efforts to eradicate the disease world-wide. Historically, the polio virus has been noted to move extremely quickly within susceptible populations- just one case of Polio could render up to 100,000 other people vulnerable to this crippling disease.[vii]

Data of new cases collected over the past 18 months by epidemiologists from the World Health Organization (WHO), is particularly harrowing. The vast majority of the cases out of previously polio-free west and central African countries of Benin , Burkina Faso , Cameroon , Central African Republic , Chad , Côte d’Ivoire , Ghana and Togo , have been genetically linked to the poliovirus endemic in northern Nigeria . So far nearly a dozen children have been paralyzed![viii]

 Other cases of polio, genetically linked to the wild Polio strain from Nigeria , have been recorded in countries as far flung as the Sudan and Botswana – a previously Polio free nation. This development should serve as a wake-up call for the government of Nigeria , and indeed, the rest of the world for immediate, consolidated action!

SEEDS OF DISTRUST: “Once bitten twice shy”[ix]

Recent explanations from certain quarters for the Polio immunization campaign resistance in northern Nigeria as due to ‘religious fundamentalism’ or “purely anti-western sentiment gone awry” are both simplistic and unhelpful. Even though both explanations may have some merit, to truly begin to fully understand why inhabitants of northern Nigeria have become increasingly wary of vaccine initiatives, one must travel back in time to 1996, to the same region of the country, when an outbreak of bacterial meningitis in Nigeria claimed scores of lives.

Pfizer, Meningitis and a Law Suit

During that public health emergency, Pfizer, the pharmaceutical giant, obtained permission from the Nigerian government and the U.S. Food and Drug Administration (FDA) to test the then-experimental oral form of the antibiotic Trovan (the trade name for Trovafloxacin) on this population. US and Nigerian medical teams from Pfizer and Johns Hopkins Medical School in Baltimore , U.SA, administered the drug to about 100 children, randomized from a population of sick children. An equal number of patients received a proven efficacious drug Ceftriaxone, in the control group.[x]

In a complaint, filed in a Federal district court in New York City following the epidemic and antibiotic study, families in Kano assert that “Eleven of the enrolled children in the Trovan study--including both treated and control patients--died, and others became paralyzed or deaf. They accused New York-based Pfizer Inc of using an experimental meningitis drug on patients without fully informing them of the risks. The plaintiffs allege that Pfizer researchers violated international law by failing to obtain informed consent from the families. The families allege that Pfizer increased the risk of death and injury by failing to provide the proven treatment to patients who did not improve after swallowing Trovan and by giving control patients a weakened version of the standard therapy”.[xi]

“Pfizer rejects the charges, saying in a statement that it is ‘proud of the way the study was conducted,’ the study was ‘well conceived and well executed,’ and it ‘saved lives.’ The company says it obtained prior consent from both the Nigerian government and patients' families.”[xii]

It is clear that Pfizer believes that its actions were altruistic and utilitarian. Some medical experts agree. Other medical experts, medical ethicists and skeptics have a differing view. The consensus amongst this second group is that several medical and ethical codes for conducting research - the Nuremberg code of 1947 and the declaration of Helsinki drawn after medical experimentation on Jews during the second world - were ignored by Pfizer. They raise the fact that the class of medications tested on these children to which Trovafloxacin belongs – the Quinolones- is strictly prohibited for use in children in the United States and much of the developed world. The effects of quinolones on bone maturation and as etiological agents of arthropathies and cartilage deterioration in the pediatric age group are well documented.[xiii]

Equally disturbing to these same observers is the fact that since the meningitis case, the antibiotic Trovan has been associated with more than 140 cases of liver toxicity around the world,[xiv] with 14 of the patients experiencing liver failure, 4 requiring liver transplants and six of the patients dying! Also alarming is the fact that the U.S. regulators advised doctors to restrict Trovan use to patients with serious diseases ‘whose need was great enough to outweigh the risks of liver damage’. In Europe , regulators went even further, suspending indefinitely, the use and sale of Trovan![xv]

 The families from Northern Nigeria see the Trovan/Meningitis case as “the Nigerian Tuskegee experiment”.[xvi] “Zubairu Shaba , who has lobbied the Nigerian government, unsuccessfully so far, for compensation on behalf of the Pfizer patients' families, said he and others distrust the entire Western and Nigerian medical establishment.”[xvii]

The Polio vaccine controversy: Tainted or not?

Compounding this already murky milieu is the recent revelations of Polio vaccine contamination, published recently in The New Scientist, and circulated in truncated versions around the world through the mass media. An important section of the study that is repeatedly quoted follows (in paraphrased form): “Hundreds of millions of people in Asia , Africa and Eastern Europe may have been injected with a Soviet polio vaccine contaminated by a monkey virus that may be linked to cancer. Shoddy standards in Soviet vaccine plants meant that decontamination of the so-called simian virus 40 (SV40) was only 95%, the New Scientist report says. This meant that for nearly 20 years after SV40 was supposed to have been eliminated, the Soviet Union continued to export potentially infected vaccines. The vaccine was almost certainly used throughout the Soviet bloc and [was] probably exported to China , Japan and several countries in Africa ," the report says.” That means hundreds of millions could have been exposed to SV40 after 1963.” [xviii]

The latest research, published in the Journal of the National Cancer Institute, categorically states that any such links between the vaccine and cancer in humans is extremely unlikely.[xix] The study was cautious not to make the claim that the vaccines were not contaminated (as they were), but refuted clearly the link to a particular kind of cancer.[xx] Several studies have come out to demonstrate clearly that the world’s supply of Polio vaccine today is safe and that the Soviet case was an incongruity, albeit an epic one.

A similar controversy over a possible link between the polio vaccine and HIV/AIDS has summarily and squarely been squashed and disproved. ‘The Polio vaccine /AIDS theory holds that chimpanzees from the Kisangani (previously Stanleyville) area in the Democratic Republic of Congo that were purportedly used in the preparation of OPV (oral polio vaccine), transmitted a SIVcpz (Simian immunodeficiency virus) to humans’ and this may very well have been the source of HIV in humans. Evidence against this theory had been piling up for decades, but became a shut case following the publication of a watershed article in Nature titled “Contaminated polio vaccine theory refuted,” by M. Worobey et al., earlier this year.[xxi]

The Role of political ineptitude, the Far Right and Anti Western sentiment in creating the Polio Epidemic

Interviews of medical practitioners working in the northern states of Nigeria , report that several local leaders and elders in this region were armed with truncated versions of the swirling scientific controversies about the polio vaccine purity and its unsubstantiated link to AIDS. One particular widespread myth was that the Polio vaccine initiatives were “a western plot to sterilize Nigerians and to give them AIDS”. Unfortunately, one thing public health professionals know too well is that “bad news and inconclusive, even bad science” travels much faster than good.

Whether the leadership in a few northern Nigerian states used half baked scientific facts to scare and mislead Nigerian citizens in order to serve a different agenda is up for debate and history to judge. What is particularly clear is the role of some far right leaning, educated northern intellectual and religious leaders who fanned the apprehension of northern states surrounding the polio vaccine, and eventually pushed for the suspension of the vaccination campaign until a thorough investigation was carried out.[xxii] That “thorough investigation” has resulted in making Kano the epicenter of a growing Polio epidemic that has affected several hundred children (some estimates place upwards of 197 Nigerian children partially of totally paralyzed), following the suspension of immunization in the north of the country late last year.

A prominent Nigerian intellectual reminds us: “Kano, let us remember, is the home of Aminu Kano, Abubakar Rimi and Ado Bayero – world class statesmen with temperate political, ideological and religious views….What we have witnessed there and throughout Nigeria is the hijacking of our country by individuals much less prepared to lead…while they bicker, our children are dying and being paralyzed by a completely preventable disease…Where is the triumph in that?”[xxiii]

The announced plans to import vaccines from Indonesia and not from the west, while acceptable (as long as the vaccines are efficacious), continues to create, to the world community at least, the sense of “intolerant religious and ideological histrionics gone too far”. There also appears to be a complete governmental lack of leadership in making Polio vaccines domestically under international standards. Surely, that would assuage even the most vitriolic critic of vaccine campaigns!

 As if painfully aware of these facts, Kano state press director Sule Yau Sule put a different spin on the issue in a recent statement: “The vaccines are in Indonesia, where they have obtained a certificate of safety, and will be tested when they arrive this week….We are not importing from Indonesia because it is a Muslim country, but because the vaccines they are producing contain safe levels of estrogen, which can be harmful to young girls,” he added.[xxiv]  Be that as it may, there is indisputable scientific evidence that the CURRENT WORLD SUPPLY OF POLIO VACCINES PARTICULARLY THAT SANCTIONED BY THE WHO (AND OFTEN MANUFACTURED IN THE WEST) IS SAFE!

Finally, it is evident that the vaccine boycott in Nigeria, ill-advised as it clearly was, was informed by a complex interplay of bad science; unclear political and religious agendas; a history of vulnerability and perceived betrayal by government, the medical establishment and big business; and a conceivably genuine, albeit misplaced and ineffective (with possibly catastrophic consequences) attempt by the local leadership to protect the inhabitants of the area.[xxv]

 Having dug through the genesis of the polio vaccine boycott in northern Nigeria, it is crystal clear that one of the most harrowing public health emergencies is at hand and all quarters must now join together to contain this burgeoning epidemic!

SOULUTIONS/STRATEGIES

 THE VACCINATION CAMPAIGN

Nigeria

Nigeria must embark upon an aggressive, vigorous and sustained immunization campaign to cover not just the vulnerable in Kano and surrounding states but children and all others at risk throughout the country. This effort will require significant financial assistance and political commitment from the Federal government of Nigeria . In particular, the local leadership must show as much zeal in restarting the vaccination campaign as it showed in bringing it to a halt.

Subpopulations that must also receive vaccinations are travelers to areas or countries where poliomyelitis is or may be epidemic or endemic; laboratory and health care workers handling specimens or who come in close contact with patients that may be excreting the virus; unvaccinated adults whose children will be receiving OPV (the Oral form of the vaccine that contains attenuated poliovirus); unvaccinated adults and incompletely vaccinated adults  in epidemic and endemic areas of Nigeria should also receive polio vaccination preferably IPV (the inactivated Polio vaccine).  Other groups that need to be covered by the vaccination campaign include pregnant women; household contact of persons with immunodeficiency diseases; patients with altered immune states; patients with immunosuppression due to therapy for other diseases or known HIV infection. All these patients in this latter group should receive IPV (the inactivated Polio vaccine).[xxvi]

Surrounding Countries

David Heymann, the WHO’s polio eradication chief points out that the Nigerian Polio epidemic “has placed approximately 74 million children at risk of polio,”[xxvii]. To combat this threat “The Global Polio Eradication Initiative, which brings together WHO and other organizations, started a $10m immunization campaign in the four neighboring countries plus Benin , aiming to reach every child with polio vaccine in just three days. Further programs are planned in Chad and Cameroon . WHO urged 22 countries in Africa to hold a massive vaccination campaign in October and November to set up an "immunity barrier" around the epicenter of the epidemic in Kano and to stop the import into countries further afield.”[xxviii] . According to Bruce Aylward of WHO the immunization efforts will “require an additional 100 million dollars over the next two years, including 25 million by August if we are to limit the damage”[xxix]

Eradication Strategies[xxx]

·        Energize the Nigerian Polio Initiative

·        Involve more completely the WHO, Save the Children and other UN and well established NGOs in the fight

• Appoint a public health emergency response team - Emergency Health Committee (EHC) - headed by trusted, distinguished and committed health professionals, preferably from the area affected. The public health team should also be set up to reflect the cultural and religious needs of the area affected.[xxxi] Public Health Team leaders should be charged with:

A)    Assembling the public health team and advising the government on any necessary equipment, budgetary and manpower needs; [xxxii]

B)     Directing the public health team toward the control/management of the emergency in a close working relationship with the aforementioned foreign agencies [xxxiii]

C)    Creating the infrastructure needed for onsite training of further volunteers and health care workers; Providing any necessary briefing including on route to field situations and monitoring the safety and well-being of the team[xxxiv]

D)    Creating a Public Education strategy that involves the media, schools as well as religious and traditional leaders and councils. This strategy should aim to develop and implement public education by providing up-to-date, authoritative information relating to the public health emergency. It is absolutely important that educational program be sensitive to the cultural and religious norms/beliefs of the people it wishes to educate[xxxv]

E)     Setting up a Water and Food Unit that can provide expert advice and assistance relating to supply of clean water, the identification and control of contaminated or polluted water, disruption to water and the sewerage systems and flooding. Also important would be assessing food hygiene in emergency areas as well as any food poisoning/contamination incidents etc.[xxxvi]

F)     Serving as important community liaison with community health centers, the Traditional leadership and municipal councils on strategies to eradicate the epidemic.[xxxvii]

Key Participating and Support facilities, groups and agencies

·        Hospitals, Health Centers , Laboratories

In this emergency, hospitals, laboratories and other scientific services should be called upon to assist with notifications, blood sampling, identification and treatment of the sick. They may also play a role in surveillance, monitoring, reporting and registration procedures. Also pivotal in the eradication campaign must be smaller rural community health centers. [xxxviii]

·        Religious and Traditional leadership, Women’s’ groups

The close involvement of the religious and traditional leadership and municipal councils and women’s groups is critical. Important also are counselors and counseling services armed with the ethnic/cultural sensitivity and understanding of the far reaching consequences of the epidemic. [xxxix]

The Role of the Media

The media’s role is crucial in providing correct and appropriate scientific and public health information and dispelling any concerns about public safety, exploitation or manipulation. There should be a coordinated flow of information between the Emergency Health Committee, its media unit, the outside media and relevant government and support agencies. The Public health team must make sure to keep its media unit regularly informed; arrange for the issue of regular bulletins for distribution within the Public health structure and to the general public; and provide assistance where required i.e. explanations and clarifications. The team must also ensure media information primarily reaches priority targets. Of particular importance is to make sure that information reaches the non-English-speaking public effectively in indigenous languages.[xl]

When asked by a journalist whether Africa had any hope given all the problems it faces, Chinua Achebe replied “ Africa is older than problems”. It is with that sense of historical resilience that we must face this new challenge. It is critical to set aside religious, political and ideological differences and work in close relationship with local and international health care organizations to eradicate Polio once and for all from Nigeria . The potential costs of inaction are enormous and all parties involved should, for the sake of the children and posterity, work together to halt this looming public health menace.

Chidi Chike Achebe is the Medical Director of Whittier Street Health Center in Boston, USA .