title: Biennial versus annual treatment for schistosomiasis and its impact on liver morbidity.
abstract: OBJECTIVE
  This study assessed the impact of annual versus biennial praziquantel treatment regimens on the prevalence, intensity of infection, and liver fibrosis dynamics of Asiatic schistosomiasis (caused by Schistosoma japonicum) among individuals residing in 18 endemic barangays in Northern Samar, Philippines.
  
  
  METHODS
  Five hundred and sixty-five subjects who reported symptoms of gastrointestinal illness and/or were believed to have clinical morbidity based on physical examination were selected for cohort follow-up.
  
  
  RESULTS
  The mean prevalence of schistosomiasis was 34% and the mean intensity of infection was 123.1 eggs per gram. Moderate to severe hepatic fibrosis (grade II/III) was demonstrated in approximately 25% of the study population. As expected, a greater reduction in both the prevalence and intensity of infection was documented with two treatment rounds versus one. Overall, hepatic fibrosis (grades I-III) regressed in only 24.3% of those who received a single treatment and in only 19.3% of those who received two doses. The prevalence of grade II-III fibrosis at baseline (25.2%) remained unchanged 2 years after treatment.
  
  
  CONCLUSIONS
  These findings suggest that in order to reverse moderate to severe liver fibrosis due to schistosomiasis and improve clinical outcomes, a higher clinical dosage of praziquantel (i.e., 60-80mg/kg) may be required over an extended duration.
authors.affiliation: Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia.
authors.forename: David U
authors.initials: DU
authors.lastname: Olveda
authors.affiliation: Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia; Research Institute for Tropical Medicine, Department of Health, Muntinlupa, Philippines.
authors.forename: Marianette T
authors.initials: MT
authors.lastname: Inobaya
authors.affiliation: QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.
authors.forename: Donald P
authors.initials: DP
authors.lastname: McManus
authors.affiliation: Research Institute for Tropical Medicine, Department of Health, Muntinlupa, Philippines.
authors.forename: Remigio M
authors.initials: RM
authors.lastname: Olveda
authors.affiliation: Research Institute for Tropical Medicine, Department of Health, Muntinlupa, Philippines.
authors.forename: Marilyn L
authors.initials: ML
authors.lastname: Vinluan
authors.affiliation: Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia.
authors.forename: Shu-Kay
authors.initials: SK
authors.lastname: Ng
authors.affiliation: Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA.
authors.forename: Donald A
authors.initials: DA
authors.lastname: Harn
authors.affiliation: QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia; Hunan Institute for Parasitic Diseases, WHO Collaborating Centre on Schistosomiasis Control in Lake Regions, Yueyang, Hunan, China.
authors.forename: Yuesheng
authors.initials: Y
authors.lastname: Li
authors.affiliation: Research Institute for Tropical Medicine, Department of Health, Muntinlupa, Philippines.
authors.forename: Jerric R
authors.initials: JR
authors.lastname: Guevarra
authors.affiliation: Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia.
authors.forename: Alfred K
authors.initials: AK
authors.lastname: Lam
authors.affiliation: Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia. Electronic address: a.ross@griffith.edu.au.
authors.forename: Allen G P
authors.initials: AG
authors.lastname: Ross
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002648:Child; D002675:Child, Preschool; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000453:epidemiology / Q000209:etiology / Q000401:mortality* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D010679:Philippines / Q000453:epidemiology; D011223:Praziquantel / Q000008:administration & dosage*; D012549:Schistosoma japonicum / Q000187:drug effects; D012552:Schistosomiasis / Q000188:drug therapy* / Q000453:epidemiology / Q000401:mortality / Q000469:parasitology; D055815:Young Adult
chemical_list: D011223:Praziquantel
keywords: Dosage; Morbidity; Schistosomiasis; Treatment