Global & Disaster Medicine

Archive for the ‘Polio’ Category

WHO: All about polio


Key facts

  • Polio (poliomyelitis) mainly affects children under 5 years of age.
  • 1 in 200 infections leads to irreversible paralysis. Among those paralysed, 5% to 10% die when their breathing muscles become immobilized.
  • Cases due to wild poliovirus have decreased by over 99% since 1988, from an estimated 350 000 cases then, to 33 (1) reported cases in 2018.
  • As long as a single child remains infected, children in all countries are at risk of contracting polio. Failure to eradicate polio from these last remaining strongholds could result in as many as 200 000 new cases every year, within 10 years, all over the world.
  • In most countries, the global effort has expanded capacities to tackle other infectious diseases by building effective surveillance and immunization systems.


Polio is a highly infectious disease caused by a virus. It invades the nervous system, and can cause total paralysis in a matter of hours. The virus is transmitted by person-to-person spread mainly through the faecal-oral route or, less frequently, by a common vehicle (for example, contaminated water or food) and multiplies in the intestine. Initial symptoms are fever, fatigue, headache, vomiting, stiffness of the neck and pain in the limbs. 1 in 200 infections leads to irreversible paralysis (usually in the legs). Among those paralysed, 5% to 10% die when their breathing muscles become immobilized.

People most at risk

Polio mainly affects children under 5 years of age.


There is no cure for polio, it can only be prevented. Polio vaccine, given multiple times, can protect a child for life.

Global caseload

Wild poliovirus cases have decreased by over 99% since 1988, from an estimated 350 000 cases in more than 125 endemic countries then, to 33 (1) reported cases in 2018.

Of the 3 strains of wild poliovirus (type 1, type 2, and type 3), wild poliovirus type 2 was eradicated in 1999 and no case of wild poliovirus type 3 has been found since the last reported case in Nigeria in November 2012.

WHO Response

Launch of the Global Polio Eradication Initiative

In 1988, the Forty-first World Health Assembly adopted a resolution for the worldwide eradication of polio. It marked the launch of the Global Polio Eradication Initiative (GPEI), spearheaded by national governments, WHO, Rotary International, the US Centers for Disease Control and Prevention (CDC), UNICEF, and supported by key partners including the Bill & Melinda Gates Foundation. This followed the certification of the eradication of smallpox in 1980, progress during the 1980s towards elimination of the poliovirus in the Americas, and Rotary International’s commitment to raise funds to protect all children from the disease.


Overall, since the GPEI was launched, the number of cases has fallen by over 99%.

In 1994, the WHO Region of the Americas was certified polio-free, followed by the WHO Western Pacific Region in 2000 and the WHO European Region in June 2002. On 27 March 2014, the WHO South-East Asia Region was certified polio-free, meaning that transmission of wild poliovirus has been interrupted in this bloc of 11 countries stretching from Indonesia to India. This achievement marks a significant leap forward in global eradication, with 80% of the world’s population now living in certified polio-free regions.

More than 16 million people are able to walk today, who would otherwise have been paralysed. An estimated 1.5 million childhood deaths have been prevented, through the systematic administration of vitamin A during polio immunization activities.

Opportunity and risks: an emergency approach

The strategies for polio eradication work when they are fully implemented. This is clearly demonstrated by India’s success in stopping polio in January 2011, in arguably the most technically-challenging place, and polio-free certification of the entire South-East Asia Region of WHO occurred in March 2014.

Failure to implement strategic approaches, however, leads to ongoing transmission of the virus. Endemic transmission is continuing in Afghanistan, Nigeria and Pakistan. Failure to stop polio in these last remaining areas could result in as many as 200 000 new cases every year, within 10 years, all over the world.

Recognizing both the epidemiological opportunity and the significant risks of potential failure, the “Polio Eradication and Endgame Strategic Plan” was developed, in consultation with polio-affected countries, stakeholders, donors, partners and national and international advisory bodies. The new Plan was presented at a Global Vaccine Summit in Abu Dhabi, United Arab Emirates, at the end of April 2013. It is the first plan to eradicate all types of polio disease simultaneously – both due to wild poliovirus and due to vaccine-derived polioviruses.

Future benefits of polio eradication

Once polio is eradicated, the world can celebrate the delivery of a major global public good that will benefit all people equally, no matter where they live. Economic modelling has found that the eradication of polio would save at least US$ 40–50 billion, mostly in low-income countries. Most importantly, success will mean that no child will ever again suffer the terrible effects of lifelong polio-paralysis.

Polio, Pakistan, and Politics


“……Pakistan has had 17 cases of polio paralysis this year; it had only three by this date last year, and only 12 in all of 2018.

In mid-April, widespread panic among parents in Peshawar and the surrounding northern tribal areas forced the suspension of a national immunization drive.

A scaremongering video spread on Twitter, purporting to show students collapsing after getting an expired batch of vaccine…..”


Statement of the Nineteenth IHR Emergency Committee Regarding the International Spread of Poliovirus


The nineteenth meeting of the Emergency Committee under the International Health Regulations (2005) (IHR) regarding the international spread of poliovirus was convened by the Director General on 27 November 2018 at WHO headquarters with members, advisers and invited Member States attending via teleconference.

The Emergency Committee reviewed the data on wild poliovirus (WPV1) and circulating vaccine derived polioviruses (cVDPV).  The Secretariat presented a report of progress for affected IHR States Parties subject to Temporary Recommendations.  The following IHR States Parties provided an update on the current situation and the implementation of the WHO Temporary Recommendations since the Committee last met on 15 August 2018: Afghanistan, Democratic Republic of the Congo (DR Congo), Nigeria, Niger, Papua New Guinea (PNG), and Somalia.

Wild polio

The Committee commended the continued high level commitment seen in Afghanistan and Pakistan, and the significant degree of cooperation and coordination, particularly in reaching high risk mobile populations that frequently cross the international border.  The committee noted that it is four years since there has been international spread outside of these two epidemiologically linked countries.

However, the Committee was very concerned by the increase in WPV1 cases globally in 2018, especially regarding the increased number of WPV cases in Afghanistan.  Furthermore, after a 10-month period of no international spread of wild poliovirus between the two neighbors, Pakistan and Afghanistan, cross border spread in both directions has occurred in the last three months.

In Pakistan the situation in 2018 has stagnated, with the number of cases so far at the same level in 2018 as for the whole of 2017.  Furthermore, positive environmental isolates in 2018 continue to be widely spread geographically indicating multiple areas of transmission and missed susceptible population groups.  Nevertheless, the performance of the eradication program has shown some improvement in areas such as SIA quality.

In Afghanistan, the number of polio cases has almost doubled in 2018, with 19 cases reported so far, compared to 10 at the same time last year, due to worsened security and greater inaccessibility, and persistent pockets of refusals and missed children.  Environmental surveillance is also finding an increased proportion of positive samples.  The security situation and access would need to significantly improve for eradication efforts to progress, as currently 1 million children under 5 years old are inaccessible in recent polio immunization campaigns.

It is now more than two years since the last WPV1 was detected in an accessible area of Nigeria, and four years since there has been any international spread of WPV1 from the country.  The Committee commended the strong efforts to reach inaccessible and trapped children in Borno, Nigeria, even in the face of increased insecurity, and noted that the inaccessible target population was now down to around 70,000 children, scattered across Borno in smaller pockets.

Vaccine derived poliovirus

The outbreaks of cVDPV2 in Somalia, Kenya, DR Congo, Niger and cVDPV1 in PNG and cVDPV3 in Somalia continue to be of major concern, particularly the apparent international spread between Somalia and Kenya and the recent spread from Nigeria into Niger of cVDPV2, given that traditionally cVDPV viruses have rarely spread across borders.  Conflict and population movement within and outside DR Congo indicate a degree of risk of spread.
Large inaccessible areas of Somalia are a significant constraint on achieving interruption of transmission of the cVDPV2 and cVDPV3 in the area, exacerbated by large population movements into and out of these areas.
Nevertheless because of the limited supply of IPV, in cVDPV type 2 outbreaks the implementation of the Temporary Recommendations for border immunization of departing travelers can be difficult.  The committee noted the progress made with cross border cooperation between PNG and Indonesia, but was concerned that new cases of cVDPV1 in new provinces of PNG had been detected in the last three months, and that surveillance indicators in Indonesian provinces neighboring PNG were sub-optimal. Similarly, countries neighboring Somalia, such as South Sudan, Ethiopia and Djibouti, have areas of weak surveillance which poses the risk that international spread may go undetected.  The outbreak of cVDPV2 in Syria has been successfully controlled with no international spread, and Syria is no longer considered infected but remains vulnerable.

The committee noted that in all infected countries, routine immunization was weak.  The outbreaks of cVDPV2 in Jigawa, and for the second time in Sokoto, Nigeria, again underlines the vulnerability of northern Nigeria to poliovirus transmission.  Routine immunization coverage remains very poor in many areas of the country, although the political leadership and national emergency programme to strengthen routine immunisation is beginning to make an impact in some areas.


The Committee unanimously agreed that the risk of international spread of poliovirus remains a Public Health Emergency of International Concern (PHEIC), and recommended the extension of Temporary Recommendations for a further three months. The Committee considered the following factors in reaching this conclusion:

  • Although the declaration of the PHEIC and issuance of Temporary Recommendations has reduced the risk of international spread of WPV, progress is fragile, and should international spread now occur, the impact on WPV eradication would be even more grave in terms of delaying certification and prolonging requirements for dedicated human and financial resources in support of the eradication effort. The reversal in progress in Afghanistan and the stagnation in Pakistan with exportation of WPV continuing between the two countries, heighten concerns.
  • There is a risk of global complacency as the numbers of WPV cases remains low and eradication becomes a tangible reality, and a concern that removal of the PHEIC now could contribute to greater complacency.
  • Many countries remain vulnerable to WPV importation. Gaps in population immunity in several key high-risk areas is evidenced by the current number of cVDPV outbreaks of all serotypes, which only emerge and circulate when polio population immunity is low as a result of deficient routine immunization programmes.
  • The international outbreak of cVDPV2 affecting Somalia and Kenya, with a highly diverged cVDPV2 that appears to have circulated undetected for up to four years, highlights that there are still high-risk populations in South and Central zones of Somalia where population immunity and surveillance are compromised by conflict.
  • Similarly the new spread of cVDPV2 between Nigeria and Niger highlights the significant risk of persisting type 2 outbreaks two years after OPV2 withdrawal, and the inability so far to prevent further spread within and outside Nigeria through application of consistently high quality mOPV2 SIAs is a concern.
  • The difficulty in controlling spread of cVDPV2 in DR Congo heightens these concerns and demonstrates significant gaps in population immunity at a critical time in the polio endgame;the low coverage with routine IPV vaccination in several countries neighboring DR Congo heightens the risk of international spread, as population immunity is rapidly waning.
  • Inaccessibility continues to be a major risk, particularly in several countries currently infected with WPV or cVDPV, i.e. Afghanistan, Nigeria and Somalia, which all have sizable populations that have been unreached with polio vaccine for prolonged periods.
  • The increasing number of countries in which immunization systems have been weakened or disrupted by conflict and complex emergencies pose another risk. Populations in these fragile states are vulnerable to outbreaks of polio.
  • The risk is amplified by population movement, whether for family, social, economic or cultural reasons, or in the context of populations displaced by insecurity and returning refugees. There is a need for international coordination to address these risks.A regional approach and strong cross­border cooperation is required to respond to these risks, as much international spread of polio occurs over land borders.

Risk categories

The Committee provided the Director-General with the following advice aimed at reducing the risk of international spread of WPV1 and cVDPVs, based on the risk stratification as follows:

  • States infected with WPV1, cVDPV1 or cVDPV3, with potential risk of international spread.
  • States infected with cVDPV2, with potential risk of international spread.
  • States no longer infected by WPV1 or cVDPV, but which remain vulnerable to re-infection by WPV or cVDPV.

Criteria to assess States as no longer infected by WPV1 or cVDPV:

  • Poliovirus Case: 12 months after the onset date of the most recent case PLUS one month to account for case detection, investigation, laboratory testing and reporting period OR when all reported AFP cases with onset within 12 months of last case have been tested for polio and excluded for WPV1 or cVDPV, and environmental or other samples collected within 12 months of the last case have also tested negative, whichever is the longer.
  • Environmental or other isolation of WPV1 or cVDPV (no poliovirus case): 12 months after collection of the most recent positive environmental or other sample (such as from a healthy child) PLUS one month to account for the laboratory testing and reporting period
  • These criteria may be varied for the endemic countries, where more rigorous assessment is needed in reference to surveillance gaps (e.g. Borno)

Once a country meets these criteria as no longer infected, the country will be considered vulnerable for a further 12 months.  After this period, the country will no longer be subject to Temporary Recommendations, unless the Committee has concerns based on the final report.


States infected with WPV1, cVDPV1 or cVDPV3 with potential risk of international spread



Afghanistan (most recent detection 25 Oct 2018)

Pakistan (most recent detection 25 Oct 2018)

Nigeria (most recent detection 27 Sept 2016)

Papua New Guinea (most recent detection 1 Oct 2018)


Somalia (most recent detection 7 Sept 2018)


These countries should:

  • Officially declare, if not already done, at the level of head of state or government, that the interruption of poliovirus transmission is a national public health emergency and implement all required measures to support polio eradication; where such declaration has already been made, this emergency status should be maintained as long as the response is required.
  • Ensure that all residents and long­term visitors (i.e. > four weeks) of all ages, receive a dose of bivalent oral poliovirus vaccine (bOPV) or inactivated poliovirus vaccine (IPV) between four weeks and 12 months prior to international travel.
  • Ensure that those undertaking urgent travel (i.e. within four weeks), who have not received a dose of bOPV or IPV in the previous four weeks to 12 months, receive a dose of polio vaccine at least by the time of departure as this will still provide benefit, particularly for frequent travelers.
  • Ensure that such travelers are provided with an International Certificate of Vaccination or Prophylaxis in the form specified in Annex 6 of the IHR to record their polio vaccination and serve as proof of vaccination.
  • Restrict at the point of departure the international travel of any resident lacking documentation of appropriate polio vaccination. These recommendations apply to international travelers from all points of departure, irrespective of the means of conveyance (e.g. road, air, sea).
  • Further intensify cross­border efforts by significantly improving coordination at the national, regional and local levels to substantially increase vaccination coverage of travelers crossing the border and of high risk cross­border populations. Improved coordination of cross­border efforts should include closer supervision and monitoring of the quality of vaccination at border transit points, as well as tracking of the proportion of travelers that are identified as unvaccinated after they have crossed the border.
  • Further intensify efforts to increase routine immunization coverage, including sharing coverage data, as high routine immunization coverage is an essential element of the polio eradication strategy, particularly as the world moves closer to eradication.
  • Maintain these measures until the following criteria have been met: (i) at least six months have passed without new infections and (ii) there is documentation of full application of high quality eradication activities in all infected and high risk areas; in the absence of such documentation these measures should be maintained until the state meets the above assessment criteria for being no longer infected.
  • Provide to the Director-General a regular report on the implementation of the Temporary Recommendations on international travel.

States infected with cVDPV2s, with potential risk of international spread

  • DR Congo(most recent detection 25 Sept 2018)
  • Kenya(most recent detection 21 March 2018)
  • Nigeria(most recent detection 17 Oct 2018)
  • Niger(most recent detection 9 Sept 2018)
  • Somalia(most recent detection 4 Oct 2018)

These countries should:

  • Officially declare, if not already done, at the level of head of state or government, that the interruption of poliovirus transmission is a national public health emergency and implement all required measures to support polio eradication; where such declaration has already been made, this emergency status should be maintained.
  • Noting the existence of a separate mechanism for responding to type 2 poliovirus infections, consider requesting vaccines from the global mOPV2 stockpile based on the recommendations of the Advisory Group on mOPV2.
  • Encourage residents and long­term visitors to receive a dose of IPV (if available in country) four weeks to 12 months prior to international travel; those undertaking urgent travel (i.e. within four weeks) should be encouraged to receive a dose at least by the time of departure.
  • Ensure that travelers who receive such vaccination have access to an appropriate document to record their polio vaccination status.
  • Intensify regional cooperation and cross­border coordination to enhance surveillance for prompt detection of poliovirus, and vaccinate refugees, travelers and cross­border populations, according to the advice of the Advisory Group.
  • Further intensify efforts to increase routine immunization coverage, including sharing coverage data, as high routine immunization coverage is an essential element of the polio eradication strategy, particularly as the world moves closer to eradication.
  • Maintain these measures until the following criteria have been met: (i) at least six months have passed without the detection of circulation of VDPV2 in the country from any source, and (ii) there is documentation of full application of high quality eradication activities in all infected and high risk areas; in the absence of such documentation these measures should be maintained until the state meets the criteria of a ‘state no longer infected’.
  • At the end of 12 months without evidence of transmission, provide a report to the Director-General on measures taken to implement the Temporary Recommendations.

States no longer infected by WPV1 or cVDPV, but which remain vulnerable to re-infection by WPV or cVDPV


  • Cameroon (last case 9 Jul 2014)
  • Central African Republic (last case 8 Dec 2011)
  • Chad (last case 14 Jun 2012)


  • Syria (last case 21 Sept 2017)

These countries should:

  • Urgently strengthen routine immunization to boost population immunity.
  • Enhance surveillance quality, including considering introducing supplementary methods such as environmental surveillance, to reduce the risk of undetected WPV1 and cVDPV transmission, particularly among high risk mobile and vulnerable populations.
  • Intensify efforts to ensure vaccination of mobile and cross­border populations, Internally Displaced Persons, refugees and other vulnerable groups.
  • Enhance regional cooperation and cross border coordination to ensure prompt detection of WPV1 and cVDPV, and vaccination of high risk population groups.
  • Maintain these measures with documentation of full application of high quality surveillance and vaccination activities.
  • At the end of 12 months* without evidence of reintroduction of WPV1 or new emergence and circulation of cVDPV, provide a report to the Director-General on measures taken to implement the Temporary Recommendations.

*For the Lake Chad countries, this will be linked to when Nigeria is considered no longer infected by WPV1 or cVDPV2.


Additional considerations

In areas where specific geographies are inaccessible, an intensive effort should be made to immunize communities on the periphery of inaccessible areas including providing immunisation posts at key transit points of high population movement.

The outbreak in Papua New Guinea is an example of the ongoing vulnerability of some parts of the world to polioviruses. The committee urged countries in close proximity to the current outbreaks, such as Ethiopia, South Sudan, Djibouti, Indonesia, Central African Republic and Lake Chad basin countries to urgently strengthen polio surveillance and routine immunization including with bOPV and IPV.  There needs to be a renewed urgency to addressing these gaps wherever they exist.  The world is at a critical point in polio eradication, and failure to boost population immunity through strengthening routine immunization, and where outbreaks have occurred through implementation of high quality SIAs, in areas of known high risk could jeopardize or severely delay polio eradication. The current situation calls for unabated efforts and use of every tool available, to achieve the goal in these most challenging countries.

The Committee noted that the extension of the PHEIC for over four years in the context of the end game of the global eradication effort, was an exceptional use of the IHR.  The committee noted that there is a legitimate debate about whether this continued declaration of a PHEIC may weaken its impact as a tool to address global health emergencies, and specifically whether it continues to have utility noting that the risk of international spread appears to have substantially diminished since 2014.  It noted that it was not originally envisaged that a PHEIC would continue for such a long period, but the committee feels that the circumstances of an eradication program such as polio are unique.  In an eradication program, it is the mere existence of the virus in a country that necessitates strenuous emergency measures, in addition to the number of cases.  The committee was concerned that the removal of the PHEIC in the current situation where exportation of WPV and cVDPV continues and progress has may even have reversed, might send out the wrong message to the global community and might weaken the gains made in reducing the risk of international spread in some areas.  There is sound evidence that the Temporary Recommendations have been an important factor in reducing the risk of international spread since 2014 [1],[2].

Based on the current situation regarding WPV1 and cVDPV, and the reports provided by Afghanistan, DR Congo, Nigeria, Niger, Papua New Guinea and Somalia, the Director-General accepted the Committee’s assessment and on 27 November 2018 determined that the situation relating to poliovirus continues to constitute a PHEIC, with respect to WPV1 and cVDPV.  The Director-General endorsed the Committee’s recommendations for countries meeting the definition for ‘States infected with WPV1, cVDPV1 or cVDPV3 with potential risk for international spread’, ‘States infected with cVDPV2 with potential risk for international spread’ and for ‘States no longer infected by WPV1 or cVDPV, but which remain vulnerable to re-infection by WPV or cVDPV’ and extended the Temporary Recommendations under the IHR to reduce the risk of the international spread of poliovirus, effective 27 November 2018.


[1] Wilder-Smith A, Leong WY, Lopez LF, et al. Potential for international spread of wild poliovirus via travelers. BMC Med 2015; 13: 133.

[2] Duintjer Tebbens RJ, Thompson KM. Modeling the costs and benefits of temporary recommendations for poliovirus exporting countries to vaccinate international travelers. Vaccine 2017; 35(31): 3823-33


There are now 12 wild poliovirus cases and 13 vaccine-derived cases reported globally in 2018.


  • Summary of new cases this week:
  • An advance notification has been received of one new wild poliovirus type 1 (WPV1) case in Afghanistan.
  • Three new WPV1 positive environmental samples have been reported from Pakistan.
  • One circulating vaccine-derived poliovirus type 2 (cVDPV2) positive environmental sample has been reported from Nigeria.
  • An advance notification has been received of one new cVDPV2 positive contact in Somalia.

A polio case in Papua New Guinea, and the virus is circulating in the community


Papua New Guinea confirms poliovirus outbreak, launches response

Joint NDOH-WHO media release

A child is protected from lifelong polio paralysis through OPV vaccination.

The National Department of Health of Papua New Guinea and the World Health Organization (WHO) today confirmed that the strain of poliovirus first detected in a child from Morobe Province in April is now circulating in the same community.

The one confirmed case is a 6-year-old boy with lower limb weakness, first detected on 28 April 2018. A vaccine-derived poliovirus type 1 (VDPV1) had been isolated as the cause of the paralysis on 21 May 2018.

On 22 June 2018, the United States Centers for Disease Control and Prevention confirmed that the same virus was also isolated from stool specimens of two healthy children from the same community. This means that the virus is circulating in the community—representing an outbreak of the virus.

“We are deeply concerned about this polio case in Papua New Guinea, and the fact that the virus is circulating,” said Pascoe Kase, Secretary of the National Department of Health (NDOH). “Our immediate priority is to respond and prevent more children from being infected.”

The NDOH has formally informed WHO and has been working with WHO and other partners in launching a response. Some of the immediate steps include conducting large-scale immunization campaigns and strengthening surveillance systems that help detect the virus early. These activities are also being strengthened in neighbouring provinces.

“Since the detection of poliovirus in April, WHO has been working with the Government on the investigation, laboratory confirmation, enhanced surveillance and response activities,” said Dr Luo Dapeng, WHO Representative in Papua New Guinea. “We will continue to support the Government to ensure children are protected.”

Papua New Guinea has not had a case of wild poliovirus since 1996, and the country was certified as polio-free in 2000 along with the rest of the WHO Western Pacific Region.

In Morobe Province, polio vaccine coverage is low, with only 61% of children having received the recommended 3 doses. Water, sanitation and hygiene are also challenges in the area.

Public health response

Outbreak response activities are ongoing in Morobe Province. Experts from the NDOH, Papua New Guinea’s Central Public Health Laboratory, Provincial Health Authorities, UNICEF and WHO have conducted field missions to undertake clinical investigation, house-to-house surveys, sample collection and contact tracing.

The team also collected stool specimens from family members of the patient and from the community. A “mop up” immunization campaign was done in the community targeting children under 15 years old. To date, 845 children from the Lufa Mountain Settlement have been vaccinated.

Circulating vaccine-derived poliovirus

Oral polio vaccine (OPV) contains an attenuated (weakened) vaccine-virus, which activates an immune response in the body. When a child is immunized with OPV, the weakened vaccine-virus replicates in the intestine for a limited period, thereby developing immunity by building up antibodies. During this time, the vaccine-virus is also excreted. In areas of inadequate sanitation, this excreted vaccine-virus can spread in the immediate community (and this can offer protection to other children through ‘passive’ immunization), before eventually dying out.

On rare occasions, if a population is seriously under-immunized, an excreted vaccine-virus can continue to circulate for an extended period of time. The longer it is allowed to survive, the more genetic changes it undergoes. In very rare instances, the vaccine-virus can genetically change into a form that can paralyze—this is what is known as a circulating vaccine-derived poliovirus (cVDPV).

Because of relatively limited travel to and from this area and the planned immunization activities, WHO assesses the risk of international spread of the cVDPV from Papua New Guinea to other countries to be low.

However, it is important that all countries—in particular those with frequent travel and contacts with polio-affected countries and areas—strengthen surveillance for cases of AFP to rapidly detect any virus importation and facilitate a rapid response. Countries, territories and areas should maintain high immunization coverage to minimize the consequences of any new virus introduction.

WHO recommends that all travellers to polio-affected areas be fully vaccinated against polio. Residents (and visitors for more than 4 weeks) from infected areas should receive an additional dose of OPV or inactivated polio vaccine (IPV) within 4 weeks to 12 months of travel.

For further information, please contact:

National Department of Health, AOPI Centre, Waigani, Port Moresby
Email: /
Phone: +675 301-3745 / +675 7206-8115

World Health Organization, 4th Floor AOPI Centre, Waigani, Port Moresby
Email: /
Phone: +675 325-7827 / +675 7197-1499 / +675 7543-7337

Nigeria: Boko Haram extremists hamper polio eradication

ABC News


Gunmen in Pakistan shot and killed two women working on a polio eradication campaign


“….Sakina Bibi, 50, and her 20-year-old daughter, Alizah, were giving immunization drops to children when two gunmen riding on a motorcycle shot them….Efforts to eradicate the disease have been undermined by opposition from militants, who say immunization is a foreign ploy to sterilize Muslim children or a cover for Western spies…….”


During the 2014–2015 outbreak of Ebola virus disease in Guinea, 13 type 2 circulating vaccine-derived polioviruses (cVDPVs) were isolated from 6 polio patients and 7 healthy contacts.


Fernandez-Garcia MD, Majumdar M, Kebe O, Fall AD, Kone M, Kande M, et al. Emergence of vaccine-derived polioviruses during Ebola virus disease outbreak, Guinea, 2014–2015. Emerg Infect Dis. 2018 Jan [date cited].

DOI: 10.3201/eid2401.171174

“…Although OPV has many advantages (easy administration by mouth, low cost, effective intestinal immunity, and durable humoral immunity), it has the disadvantage of genetic instability. Because of the plasticity and rapid evolution of poliovirus genomes and selective pressures during replication in the human intestine, vaccine poliovirus can lose key genetic determinants of attenuation through mutation or recombination with closely related polio and nonpolio enterovirus strains, acquiring the neurovirulence and infectivity characteristics of wild-type poliovirus (WPV) (3). Because of this genetic instability, in settings where a substantial proportion of the population is susceptible to poliovirus, OPV use can lead to poliovirus emergence and sustained person-to-person transmission and spread in the community of genetically divergent circulating vaccine-derived polioviruses (cVDPVs). ….”

The Global Polio Program

World Polio Day

October 24 is World Polio Day


Volunteer at one of 350 permanent transit points along the border of Pakistan vaccinates children on the move.

Message from the Director of CDC’s Center for Global Health

October 24 is World Polio Day, and it is an opportunity for the global polio eradication community to renew its promise of a polio-free world for future generations. This year’s theme is “A Celebration of the Unsung Heroes of Polio Eradication.” There are many unsung heroes working to make polio eradication possible:  vaccinators, community volunteers, frontline health care workers, surveillance and laboratory staff, and civil society.

In 2016, the world saw the lowest ever number of wild polio cases with only 37. To date in 2017, there have been 12 polio cases reported from two of the three remaining polio endemic countries:  Afghanistan (7) and Pakistan (5). Since 1988, progress against polio has been strong and consistent, with cases reduced by over 99.99%. High-quality polio vaccine campaigns and innovative methods for reaching every child have restricted the virus and put polio eradication within our reach.

The progress made in polio control has been led by the Global Polio Eradication Initiative (GPEI), a public-private partnership led by national governments with five core partners – the World Health Organization (WHO), Rotary International, the US Centers for Disease Control and Prevention (CDC), the United Nations Children’s Fund (UNICEF) and the Bill & Melinda Gates Foundation. Its goal is to eradicate polio worldwide.

CDC in Action

CDC experts are diligently working with partners to eradicate polio around the world. During World Polio Day we highlight some examples of the work done by the “unsung heroes” of this effort:

Featured Story

Unsung Heroes of Polio Eradication Since the launch of the GPEI in 1988, the number of polio cases decreased by over 99% due to the heroic efforts of everyone involved in the polio program and the sustained commitment of partners and donors. Of the many unsung heroes of polio eradication efforts, CDC provides direct support to three major programs: the Stop Transmission of Polio (STOP), the National Stop Transmission of Polio (NSTOP) Program, and the CDC polio lab. Learn more about the contributions and impacts of these programs.

Other stories include:


“Vaccinating Millions of Children in 4 Days”: Vaccinating children to protect them against vaccine preventable diseases like polio is crucial. In endemic countries where routine immunization happens at a lower rate than other areas of the world, additional strategies are used in efforts to vaccinate children. This video highlights the importance of supplemental immunization activities and the incredible efforts made by vaccination teams to vaccinate children.


Overcoming obstacles to polio eradication in PakistanGet a glimpse behind the scenes of polio eradication efforts through the eyes of a Rotarian who works to prevent this disease in her home country of Pakistan. Experience what it was like to work in an area that not only has security challenges, but was also riddled with misconceptions about the polio vaccine. Learn how these unsung heroes overcame obstacles to help Pakistan go from more than 300 polio cases in 2014 to less only 5 cases in just three years.

Other blogs include:

Photo Essays

Photo Essay

Polio Campaigns in AfricaIn 2016 there were only 4 cases of wild poliovirus in sub-Saharan Africa, all detected in Nigeria, the last polio-endemic country in Africa. In an effort to reach and protect children unreached by routine immunization services, oral polio immunization campaigns are being conducted in several African countries, with support from technical staff from CDC’s Global Immunization Division (GID)/Polio Eradication Branch/Africa team. Also available in French!

Photo Essay

At Work For ImmunizationWhen planning for routine immunizations, mass vaccination campaigns in response to outbreaks, or supplemental immunization activities, it is important to get as many people involved as possible to reach every child. Female health workers often join immunization activities because they know that vaccines work to save lives.


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