The content, links, and pdfs are no longer maintained and might be outdated.
Progress Toward Poliomyelitis and Dracunculiasis Eradication --- Sudan, 1999--2000
Sudan began poliomyelitis and dracunculiasis eradication activities in 1994 and 1995, respectively, in response to resolutions by the World Health Assembly of the World Health Organization (WHO) (1--4). Sudan poses special obstacles to global eradication campaigns as a result of the disruption caused by ongoing civil war in the vast southern part of the country. The activities of both programs are summarized in this report, which indicated that substantial progress was made to eradicate polio and control of dracunculiasis improved slightly. Continued commitment of resources, access to persons in areas of conflict, and a peaceful resolution of civil unrest are needed to eradicate both diseases.
Reported routine coverage with three doses of oral poliovirus vaccine (OPV) was 90% in northern Sudan in 1999; preliminary data for 2000 suggest that coverage was approximately 70%. In southern Sudan, routine OPV coverage was an estimated 20%, with the lowest coverage in the Upper Nile (Operation Lifeline Sudan, southern sector, unpublished data, 1999).
During 1996--2000, routine coverage was supplemented by national immunization days (NIDs) (i.e., mass campaigns that occur over a short period, in which two OPV doses are administered usually to children aged <5 years) and subnational immunization days (SNIDs) (i.e., mass campaigns conducted in large areas of a country). During 2000, four rounds of NIDs and one round of SNIDs were conducted in northern Sudan and government-controlled areas of the south. During 1996--2000, the number of children vaccinated during NIDs increased from 3.3 to 5.4 million. During 1998--2000, two NIDs rounds* were conducted annually in southern Sudan. Approximately 1.1 million children were vaccinated during the 2000 NIDs. Health-care workers traveling door-to-door to virtually inaccessible border and remote areas vaccinated an additional 500,000 children.
During 1999--2000, acute flaccid paralysis (AFP) surveillance improved, and the performance and reliability of the national poliovirus laboratory improved; it is now accredited by WHO. In the northern states and areas of the government-controlled south, the nonpolio AFP rate increased from 0.4 in 1999 to 1.3 in 2000, and adequate stool specimen§ collection from persons with AFP increased from 38% to 51% (Table 1). During the same period, the number of virologically confirmed polio cases decreased from nine to four. In southern Sudan, AFP surveillance began in 1998 and has expanded to approximately 200 sentinel reporting sites. One wild poliovirus was isolated in 1999 and none in 2000; the nonpolio AFP rate increased from 0.5 to 1.6.
Dracunculiasis (i.e., Guinea worm disease) is a parasitic infection acquired by drinking water from ponds contaminated by copepods (water fleas) that contain immature forms of the parasite. A year after the initial infection, the 30-inch (1 meter) worm(s) emerge through the skin, usually on the lower leg. Re-infection can occur; each infection lasts approximately 1 year. The peak transmission season in Sudan is May--September. No effective treatment exists; however, several measures can prevent transmission: boiling drinking water or filtering it through a finely woven cloth, preventing persons with an emerging worm from entering water, providing clean water from bore-hole wells, and treating unsafe water sources with the larvicide Abate®¶ (temephos). Ideally, health-care workers contain the disease by detecting the infected person before or within 24 hours of worm emergence and apply control measures immediately.
Since Sudan's Guinea Worm Eradication Program began during the nationwide "Guinea Worm Cease Fire" in 1995, more progress has been made in the northern part than in the southern part of the country, which has a higher incidence of dracunculiasis (5) (Figure 1); 41 indigenous cases were reported in the northern states in 2000, a decrease of 77% from the 181 reported in those states during the same period in 1999. Another 49 cases were detected in persons displaced to the northern states from the embattled southern part of the country. Of these 90 cases, 72 (80%) were contained (Table 2); 90% of the remaining villages in the northern states where dracunculiasis is endemic have at least one safe source of drinking water, and 75% of the population has been educated about preventing the disease. Among all villages where disease is endemic, 3% have water treated with Abate®.
Progress in the south was limited during 2000 because of increased civil unrest. Several international nongovernment organizations withdrew from 548 (8%) southern villages where dracunculiasis is endemic because of a dispute with the forces that control much of the south. Most control indicators improved only slightly in 2000 compared with 1999. The eradication program distributed approximately one million filters to households at risk and conducted approximately 30,000 health education sessions. During 2000, some southern states made progress; North Bahr al Ghazal reported 1097 cases, a 62% decrease from 2902 reported in 1999, and Lakes (Buheirat) reported 8227 cases, a 61% decrease from 21,102. The percentage of villages where dracunculiasis is endemic that submitted reports changed only slightly over this period, and the reliability of the reported decreases is uncertain because of variable access to the area.
Reported by: Sudan Country Office, World Health Organization, Khartoum, Sudan. WHO Suboffice for south Sudan, World Health Organization, Nairobi, Kenya. Eastern Mediterranean Regional Office, World Health Organization, Cairo, Egypt. Vaccines and Biologicals Dept, World Health Organization; WHO Collaborating Center for Research, Training and Eradication of Dracunculiasis, Geneva, Switzerland. Global 2000, the Carter Center, Atlanta, Georgia. Div of Parasitic Diseases, National Center for Infectious Diseases; Respiratory and Enteric Viruses Br, Div of Viral and Rickettsial Diseases, National Center for Infectious Diseases; Vaccine Preventable Disease Eradication Div, National Immunization Program; and an EIS Officer, CDC.
Progress in Sudan during 1999--2000 demonstrates that key polio and Guinea worm eradication strategies can have some success in countries experiencing internal conflict. Sudan's polio and dracunculiasis eradication programs have collaborated since 1995. Children were vaccinated against polio during the Guinea Worm Cease Fire, and Guinea worm program workers have assisted during NIDs. During 1999 and 2000 NIDs, health-care workers from both programs distributed 16,000 t-shirts with a polio message on the front and a Guinea worm message on the back.
Substantial progress toward polio eradication was made during 1999--2000; the nonpolio AFP rate tripled and the quality of NIDs and SNIDs implementation, local planning, supervision, and training improved. Polio eradication in Sudan will require improving stool specimen collection, expanding and strengthening the AFP surveillance system, and multiple supplemental vaccination campaigns.
Approximately 73% of reported dracunculiasis cases worldwide are from southern Sudan, making it the main source of exported cases to the northern part of the country and to Central African Republic, Ethiopia, Kenya, and Uganda. Dracunculiasis eradication will require maintaining surveillance to identify case-patients and villages where dracunculiasis is endemic, rapidly implementing control measures, and a peaceful resolution to the war. To eradicate both illnesses will require sustained national commitment with multisectoral governmental support, ensured access to persons living in areas of conflict, ongoing coordination between the northern states and rebel-held areas in southern states, and international partners to provide human and financial resources are needed to eradicate both diseases.
*In southern Sudan, NIDs were implemented with the cooperation of local health authorities and the government of Sudan, and were supported by national and international nongovernment organizations, Rotary International, the United Nations Foundation, WHO, the United Nations Children's Fund (UNICEF), the UNICEF national committees of the United States and the United Kingdom, and CDC.
Number of nonpolio AFP case-patients per 100,000 population aged <15 years. A nonpolio AFP rate of one or more nonpolio AFP cases per 100,000 children aged <15 years is the WHO-established minimum indicative of a sensitive surveillance system.
§ Two stool specimens that are collected 24 to 48 hours apart, within 14 days of paralysis onset, and that arrive at the laboratory in good condition.
¶ Use of trade names and commercial sources is for identification only and does not constitute endorsement by CDC or the U.S. Department of Health and Human Services.
Return to top.
Return to top.
Return to top.
Page converted: 4/12/2001
This page last reviewed 5/2/01