GPEI-Reaching the Hard-to-Reach: Finding polio wherever it is hiding

Roqia holds her young son, who was reported through the local surveillance network in Bamyan, Afghanistan, as having acute flaccid paralysis. ©WHO Afghanistan

The poliovirus remains in just a few small pockets around the world. However, these final hiding places are some of the most challenging settings on earth in which to eradicate a disease. Finding and stopping a virus whose special power is staying hidden is no mean feat, especially in remote or inaccessible places.

Disease detectives around the world are working tirelessly to find every last virus in these hard to reach places. Some areas are vast and sparsely populated, such as the broad plains and river beds making up areas of the Lake Chad region. Others are densely packed residential areas of Afghanistan, where security issues can sometimes make immunization difficult. In areas of Syria, civil war continues to rage through towns, communities, and families. Yet these challenges are not enough to stop the surveillance system.

Community-based surveillance

In such difficult environments, the polio surveillance system must overcome numerous challenges to ensure that the poliovirus is tracked. Experts look for the virus in children with symptoms of acute flaccid paralysis and also in water samples from sewage systems in high risk areas.

For Dr Arshad Quddus, Coordinator for the detection and interruption of poliovirus at WHO headquarters, the key to overcoming the challenges facing polio surveillance is tapping into communities. Illustrating his point, he draws a circle on a piece of paper, placing a dot in the middle. In Afghanistan, he explains, that dot represents a surveillance focal point, based at a District Health Centre or hospital. The circle extending from them is their information network – a collection of mullahs, healers, health-care providers, teachers, parents and other surveillance recruits – who have been trained to spot cases of acute flaccid paralysis in their community that could turn out to be polio.

Each volunteer is given a book in which to write down the information they find, and a phone number to call. If they come across a case in their local community, they must ring their focal point, setting in action a series of events that will allow the child to be examined, stool samples to be taken from them to be tested in the laboratory for polio and their close contacts tested.

Overcoming challenges

The system may seem simple, but insecurity, weather and challenging landscapes can be obstacles. In Afghanistan, the programme has developed creative ways to ensure that nothing stands in the way of the surveillance system being able to work as it needs to. In most cases, following the reporting of a case of acute flaccid paralysis, health workers will visit the child’s home to inspect them, and collect stool samples from the child to send for lab testing for the poliovirus. However, if the area is inaccessible, the child and their caregivers are transported to the nearest hospital in a safe area for inspection.

For Dr Quddus, the success of this system in Afghanistan is clear: “We have regular reports of where the poliovirus is circulating in difficult and hard-to-reach communities and this shows us we are being successful, despite tremendous challenges.”

Surveillance in conflict zones

These diverse methods also strengthen surveillance in countries where the security situation is rapidly changing. In Syria, the health-care system has been weakened due to conflict, with many of those at the heart of the polio surveillance system displaced. By building new networks in camps for internally displaced families where communities are created by proximity, and recruiting surveillance volunteers at the key points of entry and exit into the worst of the conflict zones, the polio surveillance system ensured that an outbreak of circulating vaccine-derived poliovirus in 2017 was rapidly identified and an outbreak response launched. The programme also thought outside of the box in Borno, Nigeria, by training medical corps being deployed to reach conflict-affected populations to spot signs of the virus.

Vaccination volunteers go tent to tent in a Syrian camp for internally displaced families, immunizing each child against polio. Some of these volunteers are also trained in surveillance, able to identify and report any child suffering from paralysis. ©WHO Syria

The polio surveillance system is strengthened by a mixture of community, adaptability, and fierce commitment to finding every last trace of virus. These are the lessons learned that help find the virus everywhere, from urban districts of Afghanistan, to hard-to-reach areas of Nigeria. For Dr Quddus, “It is the individuals on the ground willing to give their all that will enable us to achieve eradication. The surveillance system is the eyes and ears of polio eradication, showing us where to focus our best efforts to vaccinate every last child.”

A doctor and surveillance volunteer checks a child for signs of paralysis in a clinic in Shawalikot district, Afghanistan. ©WHO / Jawad Jalali

Read more in the Reaching the Hard-to-Reach series

Polio vaccination at a border crossing. ©WHO Sudan

As the world inches closer towards a polio-free future, finding and closing remaining gaps in national health system capacities to pick up traces of the poliovirus is critical. Only three countries remain on the global endemic list – Afghanistan, Pakistan and Nigeria – but the threat of poliovirus resurgence remains very real, particularly for countries with a history of importation of poliovirus from these endemic areas.

In order to ensure that surveillance systems in these ‘at-risk’ countries are up-to-scratch and sensitive enough to adequately detect and report cases of acute flaccid paralysis (AFP) – a major indicator for polio – the World Health Organization regularly leads expert reviews to put systems under the microscope.

Expert review in Sudan

Eighteen technical officers and polio surveillance experts from WHO, UNICEF, the U.S. Centers for Disease Control and Prevention, the Bill & Melinda Gates Foundation and the Eastern Mediterranean Public Health Network recently met with Ministry of Health staff in Khartoum to share their findings and recommendations after scrutinizing Sudan’s surveillance performance at federal and state levels.

“Sudan has not seen a case of polio for almost nine years, however, certain factors put it at considerable risk of poliovirus importation and outbreaks,” said Dr Naeema Al Gasseer, WHO Representative to Sudan. “It is very important that the country remains on guard against polio and continually analyses and improves the quality of its AFP surveillance, particularly in the high risk areas,” she said.

Analysing the quality of AFP surveillance reporting at the field level. ©WHO Sudan

“Strong AFP surveillance is a cornerstone of the polio eradication effort ̶ it enables us to quickly pick up poliovirus if it is circulating and react with an appropriate response,” said Dr Ni’ma Abid, a senior technical expert from WHO’s regional polio eradication hub in Amman, Jordan. “There is no margin for error and in at-risk countries facing such challenges as Sudan, we need to thoroughly examine AFP surveillance systems to make sure that they are sensitive and fast enough to detect transmission. This is a practice that will need to continue even after the world is certified polio-free,” he added.

Risk factors and special strategies

Sudan is the third largest country in Africa and home to over 40 million people. Insecurity, forced displacement, frequent nomadic population movement and inaccessibility in some areas make it challenging for health workers to consistently reach all children with vaccines to build immunity. Refugee influxes across porous borders with conflict-affected neighbouring countries exacerbate the risk of disease and compound pressures on the country’s already stretched health system. In addition, high sub-Saharan temperatures and rough expansive terrain can make timely collection and transportation of stool specimens from children with AFP for laboratory testing difficult.

Special strategies have been devised to cater for the specific surveillance challenges associated with reaching high risk groups. Examples include active searches for AFP cases and sample collection by community-based surveillance officers in areas with access issues, the mapping of the movement of displaced populations, and establishing regular communication with nomadic community focal points who report AFP cases via mobile phone. In refugee camps, vaccination posts have provided an opportunity to screen for children with AFP, and collaboration and sensitization of non-government organization (NGO) staff has helped to improve reporting of AFP cases.

Findings and the way forward

WHO surveillance officers visit a village in a high-risk area to carry out an AFP case investigation. ©WHO Sudan

Eighteen states were assessed throughout the review, with visits to 90 health facilities, the families of 16 children with AFP, and high-risk special populations. Overall conclusions were that the system is meeting global AFP surveillance targets and it is unlikely for polio to circulate undetected. However, gaps were identified that need to be addressed.

“Surveillance system performance in Sudan is sensitive and we were pleased to see implementation of the recommendations made at the last review,” said Dr Abid. “However, more attention needs to be paid to surveillance in refugee communities, cross-border population movement, and programmatic issues such as the high level of turnover of national surveillance staff,” he said. “We encourage the government of Sudan to implement the recommendations made at the review to address these and other gaps,” he said.

“WHO and partners commend the government of Sudan for its efforts to date, and stand ready to advise and support to keep the country polio-free,” said Dr Al Gasseer. “Until polio is gone for good, globally, we must make every endeavor to prevent resurgence,” she said.

Sudan witnessed its last case of indigenous wild poliovirus in 2001. Since then it has been exposed to several wild polio importations from Chad and Ethiopia with its most recent case in March 2009.

Children living in Raqqa, Syria, were immunized to rapidly raise population immunity, and stop the virus in its tracks. ©WHO Syria

The year’s end offers the chance to reflect on the polio programme’s milestones and challenges in 2017, and look ahead to what we can achieve in the coming year. 2017 saw the fewest wild polio cases in history — a total of 17 cases, or a 50% reduction from the year before—with these cases occurring in just two countries: Afghanistan and Pakistan. Yet the need to reach every last child is more important than ever, as demonstrated by surveillance gaps in Nigeria and outbreaks of vaccine-derived polio in Syria and the Democratic Republic of the Congo.

From programme strategies that helped protect progress and overcome obstacles, to commitments from donors and partners, 2017 demonstrated the resolve required to achieve a polio-free future. Accelerating progress in the new year and ending polio for good will require maintaining these political and financial commitments as well as building upon the programme’s efforts to find the virus wherever it exists.

Rooting out the virus

Throughout 2017, developments in disease surveillance – both in humans and in the environment – allowed the programme to better hone in on the virus and identify its remaining hiding places.

The drive to vaccinate every last child continued at the Afghanistan-Pakistan border. ©WHO / S.Ramo

For example, in Afghanistan, blood tests helped pinpoint which children have been reached and where gaps in immunity persist, allowing health workers to launch targeted vaccination responses. In Sudan, a pilot study used a new method of quality control to help ensure that stool samples arrive at the lab in the right condition for testing. And throughout the Eastern Mediterranean Region, environmental surveillance networks were expanded and strengthened.

These innovations are building robust, sensitive surveillance networks around the world that pick up every trace of the virus and enable the programme to develop targeted immunisation responses before polio has the chance to paralyse children.

Our surveillance teams worked to root out the virus in its remaining hiding places. ©GPEI

Overcoming challenges

The year also came with new challenges, including outbreaks of circulating vaccine-derived polio in Syria and the Democratic Republic of the Congo, where conflict has ravaged the health infrastructure. In these communities, and others where polio still exists, difficult terrain, conflict and highly mobile populations can all stand as hurdles to vaccinating children. Yet the polio programme continues to find new and effective ways of delivering vaccines.

Over 450,000 children were vaccinated against polio in Kabul, Afghanistan, in December 2017. ©WHO / Tuuli Hongisto

For example, in Afghanistan, a collaboration with a mobile circus is sharing important messages about polio vaccination with hard-to-reach populations, including those living in camps for internally displaced persons. In Pakistan, campaigns based at border crossings and train stations vaccinated children on the move who might otherwise have been missed by traditional methods. And in Syria, dedicated workers are delivering vaccines at transit points and registration centres for internally displaced persons. Thanks to these strategies, more than 255,000 children have been vaccinated in Deir Ez-Zor, 140,000 were reached in Raqqa and the programme continues to work to reach every child.

The mobile circus passed on vital health care and social messages, encouraging full immunization of every child. UNICEF Afghanistan / Ashley Graham

Renewed commitment to end the disease

Complementing these programmatic innovations were political and financial commitments that highlighted polio eradication as a priority for global health leaders. These included:

In May, the World Health Assembly reiterated the importance of eradicating polio and strategically transitioning the programme’s assets, and the G20 Health Ministers recognized the contribution of the polio infrastructure in helping countries face health emergencies during their first-ever meeting in Berlin.
At the Rotary International Convention in June, health leaders gathered and pledged US$1.2 billion to end polio. Just months later, the UK demonstrated its own longstanding commitment to eradication with a $130 million pledge.
At the G7 Health Ministers meeting in November, leaders once again affirmed their dedication to polio eradication as part of their broader commitment to strengthen health systems.

A child is vaccinated in Afghanistan during the September 2017 campaign. ©WHO / S.Ramo

Looking ahead to 2018

Next year, country programmes will need to continue working to ramp up surveillance, particularly in Nigeria, and reach children everywhere with vaccines. Cross-border coordination between Pakistan and Afghanistan, which has already had a huge impact in reducing cases, will continue to be critically important to stopping transmission.

At the same time, the global community is beginning to solidify plans for keeping the world polio-free once eradication is achieved. Countries are developing strategies for transitioning the infrastructure and tools that they currently use to fight polio. And the GPEI is working with global stakeholders and partners to develop the Polio Post-Certification Strategy, which will define the activities needed to keep polio from returning after the virus is eradicated.

If the remaining endemic countries continue to do all that they can to stop the virus, and if the global community continues to meet the level of political and financial commitment needed to make and keep children everywhere polio-free, 2018 will bring the world’s best opportunity yet to end the disease.

The tricycles are hand-crank operated by the individual to navigate the difficult roads of Burkina Faso. A wider version is also available for adults riding with children and the chairs can be tailor-made in a variety of colours. ©Rotary

Outside a sandy coloured building in a village in Burkina Faso, a young girl on crutches is making her way out onto the street. In front of her home is a new wheelchair – child-sized, brightly painted and specially adapted to the unpaved streets of her neighbourhood.

Countries around the world are united in their efforts to eradicate polio so that it will never again cause a child to be paralysed. This is important because there is no cure to this paralysing disease. For polio survivors in Burkina Faso, the opportunity to be independently mobile in their own communities can be life changing.

Independence after disability

For children living in poor communities whose limbs are paralyzed by polio, there is often very little support available to make them independently mobile. Giving a child a wheelchair puts previously inaccessible opportunities within reach so that children can reach their potential; such as going to school, playing outside with friends and learning new skills. In many cases the children are free to explore the world around them for the first time without a friend or family member to help.

Rotary International, along with partners such as Sahel, are providing support to the AMPO Association in Ouagadougou to provide services and facilities for children, teenagers, young mothers and people with disabilities often caused by polio.

Custom-made wheelchairs

The tricycles are hand-crank operated by the individual to navigate the difficult roads of Burkina Faso. A wider version is also available for adults riding with children and the chairs can be personalized in a variety of colours.

For many of those coming to the workshop, it is the first time they have had a custom-built mobility aid. They enter the workshop with assistance, but leave under their own steam.

The success of the project is largely due to the determined efforts of Project Director Edouard Norgho. He is a wheelchair user himself and so he fully appreciates the needs of his clients. Ouagadougou has more than two million inhabitants with no public transport systems, so Edouard makes sure that each wheelchair he makes is robust enough to cover long distances every day.

The five wheelchair makers at AMPO are all people with disabilities. Trained on the job, the workshop offers employment to people who often face discrimination on the labour market.

Spreading their expertise beyond the city, staff from the workshop travel further afield to reach up to 1600 people in rural areas. With the support of Rotary Germany the project receives funds and wheelchair parts, helping more and more polio survivors live a mobile life every year.

For the young girl in her new wheelchair, an exciting future awaits. In Burkina Faso more than 70% of children with disabilities have no access to education. Now, able to navigate to school by herself, she can become part of the 30% who do have the opportunity to learn. With the support of Rotary and other partners, AMPO is well on the way to helping more people like her, the target being to provide increased mobility to every polio survivor in Ouagadougou.

To find out more about this project, or provide financial support (US$250 will pay for a wheelchair for a child with disability), please visit sahel.org or contact info@sahel.de.

Edouard leads the workshop, creating custom wheelchairs for people affected by polio and other illnesses. ©Rotary

A mother helps to reduce outbreak risk by allowing her child to be immunized. © WHO

“I was told that if the child was vaccinated against polio, he could one day become a great footballer like Drogba and Yaya Toure…Today, they have not yet become like Drogba and Yaya, but they are in good health.”

– Awa B., mother of five children, Côte d’Ivoire

Today, the countries most vulnerable to poliovirus outbreaks are those where the barriers to effective immunization are most acute. In high-risk countries like the Central African Republic and Côte d’Ivoire, populations are hard to access and persuading communities of the need to vaccinate can be difficult.

For polio workers in these countries, it is important to reduce outbreak risk through strategies that involve local people, and which are receptive to the local surroundings and culture. Not every child will grow up to be a champion footballer, but by persuading parents of the importance of immunization, they can grow up active and healthy, protected from the debilitating effects of polio.

The risk of polio outbreak

The Central African Republic and Côte d’Ivoire are both considered outbreak risk countries due to their difficult political and security situations, weak health-care systems, and regular cross-border population movement.

Geographically close to Nigeria, one of the last three polio endemic countries, the Central African Republic is currently at risk of virus spread from Borno state where there was a poliovirus outbreak in 2016. In 2011, Côte d’Ivoire experienced an outbreak of wild poliovirus type 3, also originating from Nigeria.

A child is vaccinated against polio in the Central African Republic. November 2017 © UNICEF CAR

Outbreak prevention is a central part of the strategy to end polio, as the spread of the poliovirus through under-immunized populations could make eradication more of a challenge. In high risk countries where delivering vaccine can be difficult, different methods must be used to comprehensively immunize every last child.

Getting the local community involved

In Côte d’Ivoire, a round of National Polio Vaccination Days officially began on October 28^th in Ebimpé, marked by a ceremonial gathering of vaccination partners alongside key members of the local community. Speaking at the event, the Minister of Health and Public Hygiene, Dr Raymonde Goudou Coffie, described the need to vaccinate every last child as a mission for everyone: “Traditional leaders, heads of households and communities need to be involved in this initiative.”

This is a powerful method of engagement – making sure that parents and local leaders, as well as health workers and volunteer vaccinators, are involved in the fight against poliovirus.

No one approach fits all

Vaccinators also understand that no single approach will fit every situation. Instead, the Global Polio Eradication Initiative partners and field workers must work hard to understand how best to communicate the risk of polio outbreaks to different communities.

For instance, to reach parents working in Nana Mambere prefecture of the Central African Republic, local radio station SIRIRI hosted a panel based radio discussion to mark the recent vaccination campaign. Featuring medical professionals and local politicians, the panel addressed community worries around vaccine, urging every parent listening to take their young children to be immunized.

The day before the October campaign in Côte d’Ivoire, an advance team of volunteer vaccinators in Grand-Bassam began vaccinating at the local weekly market. Knowing the routine of local women, they anticipated that there would be some children visiting the market with their mothers who might not be reached later in the week – making this gathering of the community too good an opportunity to miss.

Health workers mobilize communities in Côte d’Ivoire, September 2017. © Rotary International — Health workers mobilize communities in Côte d’Ivoire. September 2017 © Rotary International

Having an understanding of the communities targeted in campaigns, whether of their worries around vaccination, or even parents’ weekly schedules, is crucial to effectively reduce the risk of a polio outbreak.

Providing broader benefits

In Côte d’Ivoire, Dr Bamba Souleymane, Departmental Director of Health in Grand-Bassam, noted the quantity of different health interventions that his team was attempting to successfully deliver. Alongside the polio vaccine, the volunteers were distributing impregnated mosquito nets, de-worming medication, and vitamins.

Such combined efforts use the GPEI’s well-established infrastructure to deliver a variety of desirable health benefits in communities, not polio vaccine alone. In places where the health infrastructure can be weak, the polio programme’s ability to reach remote children can be a big advantage for many reasons.

For Awa, the dream of her son becoming a champion footballer was a persuasive reason to take him to be vaccinated. For others, receiving different health benefits or hearing information via radio are compelling reasons to vaccinate their children.

Lowering the chance of an outbreak is never a straightforward process, but instead requires understanding parents, children, and communities.

The best vaccinators and campaign planners are able to spot opportunities to keep campaigns relevant, access groups in different ways, and ensure that coverage is sustained.

This way, we can successfully protect every last child.

Shokria, aged 4, displays her ink-stained finger to show that she has been vaccinated against polio. ©WHOEMRO 2016

In Afghanistan this year, staff from the non-governmental organization Care of Afghan Families collected 420 blood samples from children under 4 at the Mirwais Regional Hospital in Kandahar province. The aim? To find out whether polio vaccination campaigns have been reaching enough children, and whether the vaccines have been generating full protection against this paralysing disease. These ‘serosurveys’ showed that immunity in Afghanistan is high – and also identified where vaccination campaigns need to reach out further.

Whenever a polio vaccination campaign takes place, a purple dot of ink is painted onto the little finger nail of every immunised child to show that they have received the lifesaving vaccine. This data is collected and allows people to monitor the campaign and know exactly where children have been reached.

Now, with more children being vaccinated than ever before, the polio eradication programme needs to know more than how many children are being reached: we need specific data on where children are being missed.

Serosurveys testing for immunity

Serosurveys are simple tests of the serum in a child’s blood, which measures their immunity (or seroprevalence) to different diseases. The polio eradication programme uses this test to see what level of protection a child has against wild poliovirus types 1, 2 and 3, allowing them to assess whether the vaccination campaigns are reaching enough children, enough times, to give them immunity.

At the Mirwais Regional Hospital, the children tested were from a diverse range of provinces. Their results were sent to Aga Khan University for initial testing, and then sent for further analysis to one of the Global Polio Eradication Initiative partners, the US Centers for Disease Control and Prevention in Atlanta. Through mapping both where they live and their immunity results, scientists at both institutions helped polio eradicators to discover the areas where a child is at most risk of being missed by vaccination campaigns.

Serosurvey results can be crucial for planning campaign strategies – making sure that every last child is reached, no matter where they live.

Serosurveys help to map where at-risk children are living. ©WHOEMRO 2016

For Ondrej Mach, team lead for clinical trials and research in the WHO’s Polio Eradication Department, serosurveys “… are increasingly important for eradication efforts, allowing us to form an accurate picture of our progress so far, and the locations where we are being most effective.”

High immunity in Afghanistan

The Mirwais serosurvey proved that Afghanistan is closer than ever to eradicating polio, with more than 95% of children surveyed immune to wild poliovirus type 1, the virus type still circulating in some areas of Afghanistan, Pakistan and Nigeria, and more than 90% immune to type 3, which hasn’t been found anywhere in the world since November 2012. The tests also pointed to where gaps in immunity are, so that missed children can be found and protected.

These results are a strong reflection of the devoted work of polio vaccinators and community workers throughout the country, using their expertise to reach into every family, and spread awareness of the importance of polio vaccination.

Volunteer vaccinator Haji Mohammad inspects children from all over Kandahar, ensuring that no child is missed. ©WHOEMRO 2016

Using serosurveys in at-risk countries

As in Afghanistan, serosurveys are increasingly used in other countries where polio remains or poses a threat, to help identify the last remaining pockets of under-immunized children in high risk areas. This is especially important because with polio in fewer places than ever before, it is these unreached children that will take us over the finishing line.

By getting an increasingly accurate picture of where vaccination campaigns are operating successfully, as well as where the programme needs to renew efforts, we can move further towards the goal of reaching every child.

This helps us reach our ultimate goal – ensuring that every last child, everywhere, can be polio free.

Read the original interview here.

For World Polio Day on 24 October, the world celebrated the unsung heroes of the eradication effort. How important have volunteers been in eradicating polio so far?

In India, a volunteer vaccinates a child against polio. © Gavi/Manpreet Romana

Volunteers have been and continue to be the backbone of the eradication effort. Local Rotarians are raising critically-needed funds, and members of the community conduct the actual administration of the vaccines on the ground and report cases of paralysis. Without this vast network of volunteers – approximately 20 million strong worldwide – polio cannot be eradicated. They are the true unsung heroes of this effort.

What are the main hurdles to eradicating polio? Are there difficulties getting vaccines to remote communities and areas in conflict?

Those are precisely the main hurdles: reaching children who remain unreached by health systems, because of difficult terrain, conflict, security compromised access, urban sprawl, or large-scale population movements. These are all reasons some children are not vaccinated. The poliovirus is very effective at finding vulnerable children, so we have to be better than the poliovirus at finding that last unvaccinated child. And that is what we are doing with local authorities and partners. Identifying – area by area – the real reasons why children in that area are missed, and then putting in place operational action plans, at the community level, to overcome those reasons. We’re making strong progress: never before has polio been as geographically restricted as it is today. But we are not there yet, and we need to pursue our efforts.

How do you address the challenges of reliable data and identify areas with the lowest immunization coverage?

This is a key issue, particularly at this late stage of the effort, where we really have to focus on reaching the last one or two percent of children who we have so far missed. It is not good enough to achieve 95% coverage nationally, if sub-nationally we are still missing 5%-10% of children somewhere. So we need to be extremely rigorous in the monitoring of our activities, in particular when we assess population immunity levels. We have introduced a number of innovative approaches to address this challenge, such as Lot Quality Assessment sampling, to identify areas which fail to achieve campaign coverage targets; third party monitoring, to get an external view on data quality; and seroprevalence surveys, which show actual immunity levels of children in key areas or high-risk population groups. These tools provide the clearest and most reliable picture of immunity levels.

How can other disease programmes benefit from polio eradication?

Polio eradication has always been about more than polio. Rotary International calls this effort ‘PolioPlus’, with the ‘plus’ standing for more than polio. Polio-funded staff on the ground have been busy helping address other public health emergencies, from the Ebola outbreak in West Africa, the recent drought in the Horn of Africa, to the devastating earthquake in Nepal a few years ago.

Polio-funded staff have also supported Gavi’s immunization efforts, including assisting countries in their implementation of Gavi-funded vaccine and health system strengthening activities. As a concrete example, the proportion of children who have been fully immunized against all vaccine-preventable diseases in some of the most marginalised areas of India increased from less than 20% ten years ago, to more than 80% today.

These broader benefits of the polio eradication effort, however, require that countries and the international

Michel Zaffran, Director of Polio Eradication at the World Health Organization. © WHO

community make sure that the momentum is maintained when polio is eradicated. Indeed, unless this is well planned, the loss of funding coming through the Global Polio Eradication Initiative could negatively impact immunization programmes and other health interventions which have benefited from the large network of staff deployed to eradicate polio. Discussions with partners and countries are underway to map out this process for the post-polio world.

Polio eradication has indeed shown that all children – no matter where they live – can be reached with health interventions. The premise of this programme has been that every child has a right to be protected from lifelong polio paralysis, whether they live in Switzerland, or whether they live in conflict-affected areas of Somalia or areas with limited healthcare infrastructure of Afghanistan. And the lessons and experiences can be – and are being – applied to other disease control programmes.

During polio vaccination campaigns in big cities such as Cairo, Egypt, vaccinators go above and beyond to find millions of doors to knock upon to find children who need to be vaccinated. © GPEI

Rising up into the sky, a tower block’s outline trembles in the heat haze, even in the early morning. It’s hard to count the number of floors from the ground as the concrete block stretches up so high. Inside the door, you look around for an elevator – but there is none. Taking a deep breath and hoisting the vaccine carrier higher onto your shoulder, you begin the long climb up the stairs through the heat. At the top, many pauses for breath later, you knock on the first door. As a mother holding her baby opens it, your work for the day really begins – but there is a long way to go. To vaccinate every child in the city against polio, you and your fellow vaccinators must knock on every door in this building; on this street; in this neighbourhood; and across the entire city. It is a monumental task – and one you take on several times a year.

Cities: Uniquely challenging environments

Often it is the ability of polio vaccinators to reach the most remote and inaccessible villages, hampered by challenging weather or conflict, that is the biggest challenge to eradication. But big cities, while more easily accessible, can pose an equal challenge.

Dr Mohammed Sibak Abouzeid, has been working to stop polio in Egypt since 1999, planning and organising polio eradication campaigns and evaluating whether enough children were reached in each campaign so that the next one can be better. Over 40% of Egypt’s population lives in urban environments.

“While my colleagues in the countryside are battling challenging terrain, weather and long journeys, we have a different set of barriers: slums, high rise buildings, marginalised communities and big populations that can change overnight,” says Dr Mohammed. “But our goal is the same: to reach every single child, no matter where they live.”

One critical tactical shift to ensure all floors of a tower block were covered was to ensure vaccinators first walked to the top floor, and then knocked on every door coming down, rather than the other way around, which meant the very top floors were missed.

A playground for polio

Cities provide an easy environment in which for polio to spread. The poliovirus spreads between humans through faeces, so wherever sanitation systems or hygiene practices are poor, or many people live in close quarters, the virus is able to spread rapidly.

Vaccination teams go door to door in urban slums such as this. This location is also used to collect sewage water which is tested for poliovirus as part of the country’s environmental surveillance network. UNICEF/S. Biswas

The city of Karachi is one of the remaining strongholds of the virus. People move in and out of Pakistan’s biggest city constantly: these ever changing populations make it difficult to know how many children need to be vaccinated and where they live. Many children are born every day, giving the virus many opportunities to hide in the unvaccinated guts of infants who have not received at least three doses of polio vaccine. Given the informal nature of many of the slums within this city, the lack of infrastructure such as health care centres can make it especially difficult to get vaccines to every child.

Slums have another consequence for polio eradication; with high levels of poverty, malnutrition and diarrhoea are regular threats. Malnutrition can damage the immune systems of children, meaning that even if they receive the vaccine, it might not be able to kick start the process of generating protection against the virus. Diarrhoea can lead to the vaccine leaving the body too quickly for it to begin creating antibodies; but it also can act as a vehicle to cause the poliovirus to spread further and faster.

Stopping polio in cities

Stopping polio even in these challenging environments takes ingenuity and creativity. Luckily, people like Dr Mohammed have the experience necessary to make a difference.

The city of Dhaka, Bangladesh, stretches off as far as the eye can see, hiding from view the millions of children who need to be vaccinated against polio. © Gavi

“To stop polio in urban environments, you need to train all vaccinators incredibly well, and give them the motivation they need to work in difficult environments. But the most important thing is to come to understand the networks that city inhabitants are a part of so that you can engage them, involve them in vaccination campaigns and find the right influencers from local communities to encourage parents to vaccinate their children.”

In cities like Cairo in Egypt and Mumbai in India, once thought to be the hardest places in the world to stop polio, such tactics were instrumental in stopping poliovirus. Indeed, they continue to be used even now in order to ensure high vaccination coverage and keep their populations protected. It may be a matter of getting the right neighbourhood religious leader to announce vaccination campaigns during a sermon, or the right midwife to tell new mothers about vaccination, but one thing is for sure: success against polio is ensured one person at a time, even in a city of millions.

News Category: At-risk countries

Community-based surveillance

Overcoming challenges

Surveillance in conflict zones

Read more in the Reaching the Hard-to-Reach series

Expert review in Sudan

Risk factors and special strategies

Findings and the way forward

Rooting out the virus

Overcoming challenges

Renewed commitment to end the disease

Looking ahead to 2018

Independence after disability

Custom-made wheelchairs

Serosurveys testing for immunity

High immunity in Afghanistan

Using serosurveys in at-risk countries

For World Polio Day on 24 October, the world celebrated the unsung heroes of the eradication effort. How important have volunteers been in eradicating polio so far?

What are the main hurdles to eradicating polio? Are there difficulties getting vaccines to remote communities and areas in conflict?

How do you address the challenges of reliable data and identify areas with the lowest immunization coverage?

How can other disease programmes benefit from polio eradication?

Cities: Uniquely challenging environments

A playground for polio

Stopping polio in cities

Read more in the Reaching the Hard to Reach series

The growing network of disease detectives

Leaving a lasting legacy for health systems

Learn more about disease surveillance

Community-based surveillance

Overcoming challenges

Surveillance in conflict zones

Read more in the Reaching the Hard-to-Reach series

Expert review in Sudan

Risk factors and special strategies

Findings and the way forward

Rooting out the virus

Overcoming challenges

Renewed commitment to end the disease

Looking ahead to 2018

Independence after disability

Custom-made wheelchairs

The risk of polio outbreak

Getting the local community involved

No one approach fits all

Providing broader benefits

More

Serosurveys testing for immunity

High immunity in Afghanistan

Using serosurveys in at-risk countries

For World Polio Day on 24 October, the world celebrated the unsung heroes of the eradication effort. How important have volunteers been in eradicating polio so far?

What are the main hurdles to eradicating polio? Are there difficulties getting vaccines to remote communities and areas in conflict?

How do you address the challenges of reliable data and identify areas with the lowest immunization coverage?

How can other disease programmes benefit from polio eradication?

Cities: Uniquely challenging environments

A playground for polio

Stopping polio in cities

Read more in the Reaching the Hard to Reach series

The growing network of disease detectives

Leaving a lasting legacy for health systems

Learn more about disease surveillance