title: Significantly reduced intensity of infection but persistent prevalence of schistosomiasis in a highly endemic region in Mali after repeated treatment.
abstract: BACKGROUND
  Preventive chemotherapy against schistosomiasis has been implemented since 2005 in Mali, targeting school-age children and adults at high risk. A cross-sectional survey was conducted in 2010 to evaluate the impact of repeated treatment among school-age children in the highly-endemic region of Segou.
  
  
  RESULTS
  The survey was conducted in six sentinel schools in three highly-endemic districts, and 640 school children aged 7-14 years were examined. Infections with Schistosoma haematobium and S. mansoni were diagnosed with the urine filtration and the Kato-Katz method respectively. Overall prevalence of S. haematobium infection was 61.7%, a significant reduction of 30% from the baseline in 2004 (p<0.01), while overall prevalence of S. mansoni infection was 12.7% which was not significantly different from the baseline. Overall mean intensity of S. haematobium and S. mansoni infection was 180.4 eggs/10 ml of urine and 88.2 epg in 2004 respectively. These were reduced to 33.2 eggs/10 ml of urine and 43.2 epg in 2010 respectively, a significant reduction of 81.6% and 51% (p<0.001). The proportion of heavy S. haematobium infections was reduced from 48.8% in 2004 to 13.8% in 2010, and the proportion of moderate and heavy S. mansoni infection was reduced from 15.6% in 2004 to 9.4% in 2010, both significantly (p<0.01). Mathematical modelling suggests that the observed results were in line with the expected changes.
  
  
  CONCLUSIONS
  Significant reduction in intensity of infection on both infections and modest but significant reduction in S. haematobium prevalence were achieved in highly-endemic Segou region after repeated chemotherapy. However, persistent prevalence of both infections and relatively high level of intensity of S. mansoni infection suggest that more intensified control measures be implemented in order to achieve the goal of schistosomiasis elimination. In addition, closer monitoring and evaluation activities are needed in the programme to monitor the drug tolerance and to adjust treatment focus.
authors.affiliation: Institut National de Recherche en Santé Publique, BP 1771, Bamako, Mali.
authors.forename: Aly
authors.initials: A
authors.lastname: Landouré
authors.forename: Robert
authors.initials: R
authors.lastname: Dembélé
authors.forename: Seydou
authors.initials: S
authors.lastname: Goita
authors.forename: Mamadou
authors.initials: M
authors.lastname: Kané
authors.forename: Marjon
authors.initials: M
authors.lastname: Tuinsma
authors.forename: Moussa
authors.initials: M
authors.lastname: Sacko
authors.forename: Emily
authors.initials: E
authors.lastname: Toubali
authors.forename: Michael D
authors.initials: MD
authors.lastname: French
authors.forename: Adama D
authors.initials: AD
authors.lastname: Keita
authors.forename: Alan
authors.initials: A
authors.lastname: Fenwick
authors.forename: Mamadou S
authors.initials: MS
authors.lastname: Traoré
authors.forename: Yaobi
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000871:Anthelmintics / Q000008:administration & dosage*; D018890:Chemoprevention / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D019353:Endemic Diseases; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008302:Mali / Q000453:epidemiology; D008875:Middle Aged; D008962:Models, Theoretical; D010274:Parasitology / Q000379:methods; D015995:Prevalence; D012548:Schistosoma haematobium / Q000302:isolation & purification; D012550:Schistosoma mansoni / Q000302:isolation & purification; D012553:Schistosomiasis haematobia / Q000188:drug therapy / Q000453:epidemiology* / Q000473:pathology*; D012555:Schistosomiasis mansoni / Q000188:drug therapy / Q000453:epidemiology* / Q000473:pathology*; D012574:Schools; D055815:Young Adult
chemical_list: D000871:Anthelmintics