Schistosoma mansoni infection after three years of mass drug administration in Sierra Leone

Particle and Fibre Toxicology

Yaobi Zhang¹  Mary H Hodges²  Mustapha Sonnie²  Abdulai Conteh³  Florence Max McCarthy³  Mohamed S Bah²  Jusufu Paye²  Santigie Sesay³ 

[1] Helen Keller International, Regional Office for Africa, Dakar, Senegal;Helen Keller International, PO Box 352, Freetown, Sierra Leone;Neglected Tropical Disease Control Program, Ministry of Health and Sanitation, Freetown, Sierra Leone

关键词: Praziquantel;    Mass drug administration;    Sierra Leone;    Independent monitoring;    NTDs;    Neglected tropical diseases;    Schistosoma mansoni;    Schistosomiasis;   

Others  :  823288
DOI  :  10.1186/1756-3305-7-14

 received in 2013-10-31, accepted in 2014-01-06,  发布年份 2014

【 摘 要 】

Background

Schistosoma mansoni was moderately-highly endemic in the northeast of Sierra Leone. The national neglected tropical disease control program started mass drug administration (MDA) with praziquantel (PZQ) in six districts in 2009 targeting primary school children only. The effort was scaled-up to seven districts in 2010 targeting school aged children (SAC) and at-risk adults. A cross-sectional sentinel site survey was conducted in 2012 after three rounds of MDA to evaluate the impact of the national program.

Methods

Twenty-six (26) sentinel sites were randomly selected from the baseline mapping survey sites stratified according to the baseline prevalence into high, moderate or low endemic category. Fifty (50) school children (25 males and 25 females) were randomly selected per site. Fresh stool samples were examined in the field using the Kato Katz technique. The results were compared with the baseline data.

Results

Program coverage of 94.8%, 77.1% and 81.7% was reported in 2009, 2010 and 2011 respectively. Independent monitoring in 2011 showed program coverage of 83.9%, not significantly different from the reported result in the same year. The overall prevalence of S. mansoni was 16.3% (95% CI: 14.4-18.4%) and mean intensity was 18.98 epg (95% CI: 11.46-26.50 epg) in 2012, representing 67.2% and 85.9% reduction from the baseline respectively. The proportion of moderately and heavily infected children was 3.3% and 1.2%, a significant reduction from 18.2% and 8.8% at baseline respectively.

Conclusions

Sierra Leone has maintained effective MDA coverage with PZQ since 2009. Three rounds of MDA led to a significant reduction of S. mansoni infection in the country. In line with the significant progress made in controlling schistosomiasis, the national treatment strategy has been reviewed and MDA will be expanded to include school age children in low endemicity districts with the new national objective for the elimination of schistosomiasis. Sierra Leone is well on its way to eliminate schistosomiasis as a public health problem.

【 授权许可】

   
2014 Sesay et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

【 参考文献 】

• [1]Steinmann P, Keiser J, Bos R, Tanner M, Utzinger J: Schistosomiasis and water resources development: systematic review, meta-analysis, and estimates of people at risk. Lancet Infect Dis 2006, 6(7):411-425.
• [2]Hotez PJ, Molyneux DH, Fenwick A, Kumaresan J, Sachs SE, Sachs JD, Savioli L: Control of neglected tropical diseases. N Engl J Med 2007, 357(10):1018-1027.
• [3]Savioli L, Albonico M, Engels D, Montresor A: Progress in the prevention and control of schistosomiasis and soil-transmitted helminthiasis. Parasitol Int 2004, 53(2):103-113.
• [4]Stephenson LS, Latham MC, Kurz KM, Miller D, Kinoti SN, Oduori ML: Urinary iron loss and physical fitness of Kenyan children with urinary schistosomiasis. Am J Trop Med Hyg 1985, 34(2):322-330.
• [5]Friedman JF, Kanzaria HK, Acosta LP, Langdon GC, Manalo DL, Wu H, Olveda RM, McGarvey ST, Kurtis JD: Relationship between Schistosoma japonicum and nutritional status among children and young adults in Leyte, the Philippines. Am J Trop Med Hyg 2005, 72(5):527-533.
• [6]Olson CL, Acosta LP, Hochberg NS, Olveda RM, Jiz M, McGarvey ST, Kurtis JD, Bellinger DC, Friedman JF: Anemia of inflammation is related to cognitive impairment among children in Leyte, the Philippines. PLoS Negl Trop Dis 2009, 3(10):e533.
• [7]Stephenson LS, Latham MC, Ottesen EA: Malnutrition and parasitic helminth infections. Parasitology 2000, 121(Suppl):S23-S38.
• [8]Guyatt H: Do intestinal nematodes affect productivity in adulthood? Parasitol Today 2000, 16(4):153-158.
• [9]Hotez PJ, Brindley PJ, Bethony JM, King CH, Pearce EJ, Jacobson J: Helminth infections: the great neglected tropical diseases. J Clin Invest 2008, 118(4):1311-1321.
• [10]Zhang Y, MacArthur C, Mubila L, Baker S: Control of neglected tropical diseases needs a long-term commitment. BMC Med 2010, 8:67. BioMed Central Full Text
• [11]World Health Organization: Preventive chemotherapy in human helminthiasis: coordinated use of anthelminthic drugs in control interventions. Geneva: World Health Organization; 2006.
• [12]Ministry of Health and Sanitation: Sierra Leone Neglected Tropical Disease Control Master Plan 2011–2015. Sierra Leone: Freetown: Ministry of Health and Sanitation; 2012.
• [13]Gbakima AA, Sahr F: Intestinal parasitic infections among rural farming communities in eastern Sierra Leone. Afr J Med Med Sci 1995, 24(2):195-200.
• [14]World Health Organization: Atlas of global distribution of schistosomiasis. [http://www.who.int/schistosomiasis/epidemiology/en/sierraleone_liberia.pdf webcite]
• [15]Koroma JB, Peterson J, Gbakima AA, Nylander FE, Sahr F, Soares Magalhaes RJ, Zhang Y, Hodges MH: Geographical distribution of intestinal schistosomiasis and soil-transmitted helminthiasis and preventive chemotherapy strategies in Sierra Leone. PLoS Negl Trop Dis 2010, 4(11):e891.
• [16]Hodges M, Dada N, Wamsley A, Paye J, Nyorkor E, Sonnie M, Barnish G, Bockarie M, Zhang Y: Improved mapping strategy to better inform policy on the control of schistosomiasis and soil-transmitted helminthiasis in Sierra Leone. Parasit Vectors 2011, 4:97. BioMed Central Full Text
• [17]Hodges MH, Soares Magalhaes RJ, Paye J, Koroma JB, Sonnie M, Clements A, Zhang Y: Combined spatial prediction of schistosomiasis and soil-transmitted helminthiasis in sierra leone: a tool for integrated disease control. PLoS Negl Trop Dis 2012, 6(6):e1694.
• [18]Hodges MH, Sonnie M, Turay H, Conteh A, Maccarthy F, Sesay S: Maintaining effective mass drug administration for lymphatic filariasis through in-process monitoring in Sierra Leone. Parasit Vectors 2012, 5:232. BioMed Central Full Text
• [19]World Health Organization: Helminth control in school-age children: a guide for managers of control programmes. 2nd edition. Geneva: World Health Organization; 2012.
• [20]World Health Organization: Basic methods in medical parasitology laboratory. Geneva: World Health Organization; 1991.
• [21]World Health Organization: Bench aids for the diagnosis of intestinal parasites. Geneva: World Health Organization; 1994.
• [22]World Health Organization: Prevention and control of schistosomiasis and soil-transmitted helminthiasis. WHO Tech Rep Ser 2002, 912:32-33.
• [23]King CH, Dangerfield-Cha M: The unacknowledged impact of chronic schistosomiasis. Chronic Illn 2008, 4(1):65-79.
• [24]Kabatereine NB, Brooker S, Koukounari A, Kazibwe F, Tukahebwa EM, Fleming FM, Zhang Y, Webster JP, Stothard JR, Fenwick A: Impact of a national helminth control programme on infection and morbidity in Ugandan schoolchildren. Bull World Health Organ 2007, 85(2):91-99.
• [25]Koukounari A, Gabrielli AF, Toure S, Bosque-Oliva E, Zhang Y, Sellin B, Donnelly CA, Fenwick A, Webster JP: Schistosoma haematobium infection and morbidity before and after large-scale administration of praziquantel in Burkina Faso. J Infect Dis 2007, 196(5):659-669.
• [26]Landoure A, Dembele R, Goita S, Kane M, Tuinsma M, Sacko M, Toubali E, French MD, Keita AD, Fenwick A, et al.: Significantly reduced intensity of infection but persistent prevalence of schistosomiasis in a highly endemic region in mali after repeated treatment. PLoS Negl Trop Dis 2012, 6(7):e1774.
• [27]Tohon ZB, Mainassara HB, Garba A, Mahamane AE, Bosque-Oliva E, Ibrahim ML, Duchemin JB, Chanteau S, Boisier P: Controlling schistosomiasis: significant decrease of anaemia prevalence one year after a single dose of praziquantel in Nigerian schoolchildren. PLoS Negl Trop Dis 2008, 2(5):e241.
• [28]Touré S, Zhang Y, Bosque-Oliva E, Ky C, Ouedraogo A, Koukounari A, Gabrielli AF, Bertrand S, Webster JP, Fenwick A: Two-year impact of single praziquantel treatment on infection in the national control programme on schistosomiasis in Burkina Faso. Bull World Health Organ 2008, 86(10):780-787.
• [29]Zhang Y, Koukounari A, Kabatereine N, Fleming F, Kazibwe F, Tukahebwa E, Stothard JR, Webster JP, Fenwick A: Parasitological impact of 2-year preventive chemotherapy on schistosomiasis and soil-transmitted helminthiasis in Uganda. BMC Med 2007, 5:27. BioMed Central Full Text
• [30]World Health Organization: Accelerating work to overcome the global impact of neglected tropical diseases - a roadmap for implementation. Geneva: World Health Organization; 2012.
• [31]World Health Organization: Elimination of schistosomiasis. World Health Assembly, Resolution 65.21. [http://apps.who.int/gb/ebwha/pdf_files/WHA65/A65_21-en.pdf webcite.]
• [32]World Health Organization: Schistosomiasis: progress report 2001–2011 and strategic plan 2012–2020. Geneva: World Health Organization; 2012.
• [33]World Health Organization: Working to overcome the global impact of neglected tropical diseases - First WHO report on neglected tropical diseases. Geneva: World Health Organization; 2010.
• [34]Statistics Sierra Leone and ICF Macro: Sierra Leone demographic and health survey 2008. Calverton, Maryland, USA: Statistics Sierra Leone and ICF Macro; 2009.
• [35]Costa MF L e, Magalhaes MH, Rocha RS, Antunes CM, Katz N: Water-contact patterns and socioeconomic variables in the epidemiology of schistosomiasis mansoni in an endemic area in Brazil. Bull World Health Organ 1987, 65(1):57-66.
• [36]Mason PR, Patterson BA, Loewenson R: Piped water supply and intestinal parasitism in Zimbabwean schoolchildren. Trans R Soc Trop Med Hyg 1986, 80(1):88-93.
• [37]Freeman MC, Ogden S, Jacobson J, Abbott D, Addiss DG, Amnie AG, Beckwith C, Cairncross S, Callejas R, Colford JM Jr, et al.: Integration of water, sanitation, and hygiene for the prevention and control of neglected tropical diseases: a rationale for inter-sectoral collaboration. PLoS Negl Trop Dis 2013, 7(9):e2439.