Progress toward poliomyelitis eradication --- Nigeria, January 2010-June 2011

The Global Polio Eradication Initiative (GPEI) was launched by the World Health Assembly in 1988. By 2006, transmission of indigenous wild poliovirus (WPV) was interrupted in all countries except Nigeria, Afghanistan, Pakistan, and India. Among the 36 states and Federal Capital Territory of Nigeria, WPV transmission has persisted in eight northern states considered at high risk; in addition, four other northern states have been considered at high risk for WPV transmission. In these 12 high-risk states, type 2 circulating vaccine-derived poliovirus (cVDPV2) transmission also was observed during 2005-2011. This report updates GPEI progress in Nigeria during January 2010--June 2011 and describes activities required to interrupt transmission. In Nigeria, confirmed WPV cases decreased 95%, from 388 in 2009 to 21 in 2010; cVDPV2 cases decreased 82%, from 154 in 2009 to 27 in 2010. However, as of July 26, 2011, Nigeria had reported 24 WPV cases (including one WPV/cVDPV2 coinfection) and 11 cVDPV2 cases during January-June 2011, compared with six WPV cases and 10 cVDPV2 cases during January-June 2010. Despite substantial progress, immunization activities and surveillance sensitivity will need to be enhanced further to interrupt WPV transmission in Nigeria by the end of 2011.     

Progress toward global eradication of dracunculiasis, January 2009-June 2010

In 1986, the World Health Assembly (WHA) called for the elimination of dracunculiasis (Guinea worm disease), a parasitic infection in humans caused by Dracunculus medinensis. At the time, an estimated 3.5 million cases were occurring annually in 20 countries in Africa and Asia, and 120 million persons were at risk for the disease. Because of slow mobilization in countries with endemic disease, the 1991 WHA goal to eradicate dracunculiasis globally by 1995 was not achieved. In 2004, WHA established a new target date of 2009 for global eradication; despite considerable progress, that target date also was not met. This report updates both published and previously unpublished data and updates progress toward global eradication of dracunculiasis since January 2009. At the end of December 2009, dracunculiasis remained endemic in four countries (Ethiopia, Ghana, Mali, and Sudan). The number of indigenous cases of dracunculiasis worldwide had decreased 31%, from 4,613 in 2008 to 3,185 in 2009. Of the 766 cases that occurred during January--June 2010, a total of 745 (97%) were reported from 380 villages in Sudan. Ghana, Ethiopia, and Mali each are close to interrupting transmission, as indicated by the small and declining number of cases. The current target is to complete eradication in all four countries as quickly as possible. Insecurity (e.g., sporadic violence or civil unrest) in areas of Sudan and Mali where dracunculiasis is endemic poses the greatest threat to the success of the global dracunculiasis eradication program.     

Progress toward poliomyelitis eradication--Ethiopia,Somalia, and Sudan,January 2001-October 2002

Since the World Health Assembly resolved in May 1988 to eradicate poliomyelitis, the estimated number of polio cases globally has declined >99%. The number of countries in which polio was estimated to be endemic decreased from 125 in 1988 to 10 in 2001, and three World Health Organization (WHO) regions (American, European, and Western Pacific) comprising approximately 55% of the world's population have been certified polio-free. Ethiopia, Somalia, and Sudan have achieved the lowest levels of poliovirus circulation since the polio eradication initiative began and are approaching interruption of transmission. This report describes intensified polio eradication activities in these countries during January 2001-October 2002, summarizes progress made, and highlights remaining challenges. Continued political commitment and financial support will be required to eradicate polio in these countries.     

Progress toward global eradication of poliomyelitis, January 2003-April 2004

In 1988, the World Health Assembly (WHA) resolved to eradicate poliomyelitis globally. Since then, implementation of the eradication strategies reduced the number of countries with endemic polio from 125 in 1988 to six in 2003. However, in 2003, an unprecedented 10 countries reported poliovirus importations, including eight in West and Central Africa, one in Southern Africa (Botswana), and one in the Middle East (Lebanon). This report describes progress made toward global polio eradication during January 2003-April 2004, outlines remaining challenges, and underscores the need for decisive action to interrupt transmission by the end of 2004 or early 2005.     

Progress toward poliomyelitis eradication---India, January 2010--September 2011

The Global Polio Eradication Initiative was launched in 1988. In 1995, when eradication activities were initiated in India, an estimated 50,000 polio cases were occurring each year. By 2006, transmission of indigenous wild poliovirus (WPV) had been interrupted in all countries except India, Afghanistan, Pakistan, and Nigeria. During 2006--2009, India annually reported 559 to 874 cases of confirmed WPV, with cases centered in the northern states of Uttar Pradesh and Bihar. These cases accounted for 43% of confirmed cases of WPV reported worldwide during this period. However, in 2010, only 42 WPV cases were reported in India, and in 2011, only one WPV case had been confirmed as of October 31. This report updates previous reports and summarizes progress toward polio eradication in India during January 2010--September 2011. Throughout India, the most recent confirmed WPV type 3 (WPV3) case occurred on October 22, 2010, in Jharkhand, and the most recent confirmed WPV type 1 (WPV1) case occurred on January 13, 2011, in West Bengal; WPV2 has not been reported in India since 1999. Importation of WPV into India is a risk, and undetected low-level WPV transmission is a possibility, requiring high vaccination coverage in all states, continued focus on children in migrant and underserved populations, sensitive surveillance for prompt detection of any WPV, and preparedness to mount a robust emergency vaccination campaign in response to any WPV cases.     

Progress toward global poliomyelitis eradication, 2000

In 1988, the World Health Assembly resolved to eradicate poliomyelitis globally by 2000 (1). Substantial progress toward this goal has been reported from all six World Health Organization (WHO) regions; 20 countries reported poliovirus transmission in December 2000 compared with 30 in 1999. WHO has prepared a global action plan that anticipates certification of polio eradication in 2005 (2). This report summarizes the status of the eradication effort and describes the remaining tasks to be completed to reach global polio eradication     

Progress toward global poliomyelitis eradication, 1999

In 1988, the World Health Assembly resolved to eradicate poliomyelitis globally by the end of 2000. Since then, substantial progress has been made in implementing polio eradication strategies, and during 1999 these activities were accelerated to reach the global target. The number of countries where polio is endemic decreased, and the number and quality of vaccination rounds increased. Acute flaccid paralysis (AFP) surveillance improved, and political commitment and the global partnership for polio eradication strengthened. This report updates progress toward achieving the polio eradication goal during 1999.     

Progress toward poliomyelitis eradication--Eastern Mediterranean Region, 1998-October 1999

In 1988, the Regional Committee for the Eastern Mediterranean Region* (EMR) of the World Health Organization (WHO) adopted a resolution to eliminate poliomyelitis from the region by 2000. This report summarizes progress toward this goal in EMR countries through October 1999; all EMR countries, including war-torn and other underdeveloped areas of the region, are conducting essential polio eradication strategies, and eradication activities to rapidly stop poliovirus transmission are under way in countries where polio is endemic.     

Progress toward global eradication of poliomyelitis, 2001

From the initiation of the global poliomyelitis eradication initiative in 1988 through 2001, the number of countries where polio is endemic decreased from 125 to 10, and the number of reported polio cases decreased by >99% from an estimated 350,000 to <1,000. Wild type 2 poliovirus has not been detected worldwide since October 1999. The American and Western Pacific Regions of the World Health Organization (WHO) have been certified free of indigenous wild poliovirus. Current challenges to global polio eradication efforts include ongoing intense transmission in northern India, continued importations of wild poliovirus into polio-free areas, and the detection of circulating vaccine-derived poliovirus (cVDPV). This report summarizes global progress in polio eradication during 2001 and the current status of the initiative.     

Progress toward global eradication of poliomyelitis, 2002

Since the 1988 World Health Assembly resolution to eradicate poliomyelitis globally through 2002, the number of countries where polio is endemic declined from 125 to seven, and the estimated incidence of polio decreased >99%. In 2002, the European Region became the third World Health Organization (WHO) region certified as polio-free, joining the Region of the Americas and the Western Pacific Region, certified polio-free in 1994 and 2000, respectively. Despite these achievements, a provisional total of 1,920 polio cases were reported during 2002, a substantial increase from 483 in 2001, reflecting primarily the large polio epidemic in India. This report summarizes global progress achieved in polio eradication during 2002 and describes remaining challenges.     

Progress toward poliomyelitis eradication--Afghanistan and Pakistan, January 2010-September 2011

Indigenous transmission of wild poliovirus (WPV) has never been interrupted in Afghanistan, Pakistan, India, and Nigeria. Among those countries, Afghanistan and Pakistan represent a common epidemiologic reservoir. This report updates previous reports (1,4) and describes polio eradication activities and progress in Afghanistan and Pakistan during January 2010--September 2011, as of October 31, 2011, and planned activities during 2011--2012 to address challenges to polio eradication. In Afghanistan, WPV transmission during 2010--2011 predominantly occurred in the conflict-affected South Region and the adjacent Farah Province of the West Region. During 2010, 25 WPV cases were confirmed in Afghanistan, compared with 38 in 2009; 42 WPV cases were confirmed during January--September 2011, compared with 19 for the same period in 2010. In Pakistan, WPV transmission during 2010--2011occurred both in conflict-affected, inaccessible areas along the common border with Afghanistan and in accessible areas; 144 WPV cases were confirmed in 2010, compared with 89 in 2009, and 120 WPV cases were confirmed during January--September 2011, compared with 93 during the same period in 2010. In Pakistan, the president launched a National Emergency Action Plan for polio eradication in January 2011, emphasizing the key role and responsibility of political and health-care leaders at the district and subdistrict (union council) levels. Enhanced commitment, management, and oversight by provincial and district authorities will be needed to achieve further progress toward interruption of WPV transmission in Pakistan. Continued efforts also will be needed to enhance the safety of vaccination teams within insecure areas of both countries.     

Progress toward global eradication of dracunculiasis, January 2010-June 2011

In 1986, the World Health Assembly (WHA) called for the elimination of dracunculiasis (Guinea worm disease), a parasitic infection in humans caused by Dracunculus medinensis. At the time, an estimated 3.5 million cases were occurring annually in 20 countries in Africa and Asia, and 120 million persons were at risk for the disease. Because of slow mobilization in countries with endemic disease, the 1991 WHA goal to eradicate dracunculiasis globally by 1995 was not achieved. In 2004, WHA established a new target date of 2009 for global eradication; despite considerable progress, that target date also was not met. This report updates published and previously unpublished data and describes progress towards global eradication of dracunculiasis since January 2010. The number of indigenous cases of dracunculiasis worldwide decreased 44%, from 3,185 cases in 2009 to 1,793 in 2010. As of June 2011, dracunculiasis remained endemic in three countries (Ethiopia, Mali, and South Sudan). Of the 814 cases that occurred during January-June 2011, a total of 801 (98%) were reported from 358 villages in South Sudan. By October 2010, Ghana had gone 12 months without an indigenous case, thereby interrupting transmission; Ethiopia and Mali are close to interrupting transmission, as indicated by the small and declining numbers of cases in these two countries. An outbreak of 10 cases was discovered in Chad in 2010. The current target is to interrupt transmission in the remaining countries as soon as possible. Insecurity (e.g., sporadic violence or civil unrest) in areas of South Sudan and Mali, where dracunculiasis is endemic, poses the greatest threat to the success of the global dracunculiasis eradication campaign.     

Progress toward poliomyelitis eradication--Nigeria, January 2003-March 2004

Since the 1988 World Health Assembly resolution to eradicate poliomyelitis, three World Health Organization (WHO) regions (Americas, Western Pacific, and European) have been certified polio-free, and the number of countries where polio is endemic has decreased from 125 in 1988 to six in 2003 (Afghanistan, Egypt, India, Niger, Nigeria, and Pakistan). In 2003, Nigeria, the most populous country of the African continent (2003 population projected from 1991 census report: 125 million), reported 355 wild poliovirus (WPV) cases, accounting for 45% of cases reported globally and >80% of cases reported from the African Region (AFR). This report summarizes progress toward polio eradication in Nigeria during January 2003-March 2004. The findings indicate the urgent need to implement high-quality supplementary immunization activities (SIAs) in Nigeria to interrupt ongoing WPV transmission.     

Progress toward poliomyelitis eradication--Nigeria, January 2004-July 2005

After the 1988 World Health Assembly resolution to eradicate polio, the number of countries where polio is endemic decreased from 125 in 1988 to six in 2003. However, the Global Polio Eradication Initiative faced critical challenges during 2003-2005, when a resurgence of polio cases occurred across Africa. Nigeria, the most populous country of the continent, experienced increased wild poliovirus (WPV) transmission throughout the country after suspension of supplementary immunization activities (SIAs) in certain northern states because of misconceptions regarding vaccine safety. The resurgence in Nigeria resulted in the spread of WPV during 2003-2005 into 18 countries that had been polio-free for 1 or more years, including three countries outside Africa. Transmission was reestablished and is ongoing in six of these countries. The Nigerian states that suspended campaigns subsequently resumed SIAs in 2004, in synchrony with SIAs being conducted in other countries across West and Central Africa. This report summarizes polio eradication activities and WPV circulation in Nigeria during January 2004-July 2005 and the actions under way to interrupt WPV transmission.     

Progress toward poliomyelitis eradication--India, January 2006-September 2007

India is one of four countries where wild poliovirus (WPV) transmission has never been interrupted (the others are Afghanistan, Nigeria, and Pakistan). An outbreak of poliomyelitis cases caused by WPV type 1 (WPV1) occurred in India in 2006, primarily in the northern states of Uttar Pradesh and Bihar, where polio remains endemic. This outbreak resulted in the greatest annual number of cases of poliomyelitis in India since 2002. In response, the Government of India and its partners implemented additional vaccination measures based on recommendations from the India Expert Advisory Group on Polio Eradication. These measures focused predominantly on use of monovalent oral poliovirus vaccine type 1 (mOPV1), which has higher efficacy against WPV1 than trivalent OPV (tOPV). As a result, WPV1 cases in India decreased approximately 84% to 66 cases during January-September 2007, compared with 405 cases during the corresponding period in 2006. In western Uttar Pradesh, a state in which multiple risk factors have made interruption of WPV transmission challenging, five WPV1 cases have been reported this year, compared with 299 during the same period in 2006. However, a WPV type 3 (WPV3) outbreak also has been reported, with 261 cases occurring through September 30, 2007, primarily in the northern states where polio remains endemic. This report summarizes progress toward polio eradication in India during January 2006-September 2007 and highlights the challenges and strategic adaptations of eradication measures.     

Progress toward poliomyelitis eradication--India, January 2005-June 2006

The global eradication of poliomyelitis has reached a critical stage. The disease remains endemic in only four countries (Afghanistan, India, Nigeria, and Pakistan), which have reported most of the cases in 2006. India is the most populous of the polio-endemic countries. Beginning in 2005, the Government of India (GOI) and its partners intensified eradication efforts by implementing additional immunization and surveillance strategies, including introduction of monovalent oral poliovirus vaccine types 1 and 3 (mOPV1 and mOPV3, respectively). The number of reported cases decreased from 134 in 2004 to 66 in 2005. However, cases have resurged in 2006; as of June 25, 2006, a total of 60 cases had been reported. Although intense local transmission continues in certain areas (i.e., western Uttar Pradesh [UP]), interruption of wild poliovirus (WPV) transmission in India is feasible with continued effective interventions. This report summarizes progress toward polio eradication in India from January 2005 through June 2006.     

Progress toward poliomyelitis eradication--Nigeria,January 2000-March 2002

Since 1988, when the World Health Assembly of the World Health Organization (WHO) resolved to eradicate poliomyelitis globally, the annual estimated incidence of polio has declined 99%. Nigeria is the most populous country in Africa (estimated 2000 population: 127 million) and a major poliovirus reservoir. This report summarizes the progress toward polio eradication in Nigeria during January 2000-March 2002, highlighting achievements in acute flaccid paralysis (AFP) surveillance and evidence indicating reduced poliovirus transmission. The findings underscore the importance of ensuring a rapid flow of surveillance information to guide program activities.     

Progress toward poliomyelitis eradication--Angola,January 1998-June 2002

Since the World Health Assembly resolved in 1988 to eradicate poliomyelitis, the estimated number of polio cases worldwide has declined >99%. Angola began polio eradication activities in 1996. Although polio eradication efforts have been hampered by the country's 27-year-long civil war, both the incidence of polio cases and the geographic circulation of poliovirus in Angola have decreased substantially. The cessation of hostilities on April 4, 2002, presents a new opportunity to reach populations that had been inaccessible and undervaccinated previously. This report summarizes progress made during January 1998-June 2002 and highlights the remaining challenges to eradicating polio in Angola.     

Progress toward poliomyelitis eradication--India, January 2004-May 2005

Since 1988, the global incidence of polio has decreased by more than 99%, and three World Health Organization (WHO) regions (Americas, Western Pacific, and European) have been certified as polio-free . India, the largest of the six countries where polio remains endemic, experienced a large polio outbreak (1,600 cases) in 2002. Since then, the Government of India (GOI) has accelerated its polio eradication activities by increasing the number and quality of supplementary immunization activities (SIAs), which reduced the number of reported cases to 225 in 2003, 134 in 2004, and 18 in 2005 (as of June 18). During 2004 and early 2005, taking advantage of the geographic restriction of wild poliovirus (WPV) circulation, GOI and its partners launched several immunization and surveillance strategies to maximize the probability of eliminating poliovirus transmission in India. With continued high-quality interventions, interruption of WPV transmission in India by the end of 2005 appears feasible. This report summarizes progress toward polio elimination during January 2004-May 2005 toward that end.     

Progress toward poliomyelitis eradication--Nigeria,January 2002--March 2003

Since 1988, when the World Health Assembly resolved to eradicate poliomyelitis globally, the annual estimated incidence of polio has decreased >99%. Nigeria is the most populous country in Africa (estimated 2000 population: 127 million) and a major poliovirus reservoir. This report summarizes progress toward polio eradication in Nigeria during January 2002--March 2003, highlighting progress in acute flaccid paralysis (AFP) surveillance and evidence of wild poliovirus (WPV) circulation in areas of lower vaccination coverage. The findings underscore the importance of achieving high-quality supplementary immunization activities (SIAs).