Soil transmitted helminth infection in primary school children varies with ecozone in the Ngorongoro Conservation Area, Tanzania

Tropical Medicine and Health

Jennifer Hatfield¹  Frank van der Meer²  Ashley Schroeder³  Susan Kutz³  Domenica Morona⁴  Humphrey D. Mazigo⁴  Manar Eltantawy⁵  Karin Orsel⁶  Mange Manyama⁷ 

[1]Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada

[2]Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada

[3]Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada

[4]Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada

[5]Department of Parasitology, Catholic University of Health and Allied Science, Mwanza, Tanzania

[6]Department. of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada

[7]Department. of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada

[8]Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada

[9]Division of Medical Education, Weill Cornell Medicine - Qatar, Doha, Qatar

关键词: Soil transmitted helminths;    Stool;    Elementary schools;    Sanitation practices;    Diagnostic techniques;    Elevation;    BMI;    Ngorongoro Conservation Area;    Tanzania;    Strongyloides spp;   

DOI  :  10.1186/s41182-021-00310-6

来源: Springer

【 摘 要 】

BackgroundSoil-transmitted helminthiasis is a neglected tropical disease, thriving in environments of poverty and disadvantage. Our objective was to determine the prevalence and intensity of four soil transmitted helminths (STH) among primary school children in the Ngorongoro Conservation Area (NCA), Tanzania.MethodsA cross-sectional study was performed between May 15th and June 2nd, 2014. Six of 20 primary schools were chosen, based on elevation, designated low elevation ecozone (LEE) or high elevation ecozone (HEE). A total of 340 children from standards one to four were recruited. Height and weight of each child was determined and body mass index (BMI) was calculated. Stool samples were analyzed using the Kato-Katz, Wisconsin, and Baermann techniques to detect STH eggs and larvae. An interviewer-administered questionnaire on socio-demographic variables was used to capture information from the school’s headmaster and a checklist was used to assess sanitation facilities.ResultsSTHs identified included Ascaris (presumably lumbricoides), Trichuris (presumably trichiura), hookworms (presumably Ancylostoma duodenale and/or Necator americanus), and Strongyloides (presumably stercoralis). The overall prevalence of STH infection was 29.0% in LEE and 34.0% in HEE. Prevalence was 34.3% and 28.2% in males versus females, respectively. Ascaris sp. were only identified in HEE, prevalence of Trichuris sp. and hookworms were significantly higher in HEE compared to LEE, and Strongyloides spp. prevalence was lower in HEE. Intensity of Trichuris sp. was significantly higher in HEE and lower for hookworms. We did not detect a significant relationship between BMI and helminth intensity; however, BMI was lower in lower elevations and in males vs. females. Sanitation practices are taught at the schools, but challenges were identified when implementing. Latrine facilities were available and latrine-cleaning routines were practiced; however, hand washing practices were challenging due to restricted water availability.ConclusionsSignificant differences in prevalence in HEE and LEE exist, and STH infections are still very common among school children suggesting that anthelminthic intervention and education may be necessary in this region. Based on this outcome, the study area in the NCA would be classified as a medium risk area, where periodic treatment recommendations should be based on prevalence estimations in the different ecozones.Trial registrationEthics approval was obtained from the Catholic University of Health and Allied Sciences (CUHAS; Lake Zone Institutional Review Board MR/53/100/307)); the Conjoint Health Research Ethics Board (CHREB) at the University of Calgary in Canada (Study ID REB14-0127); the National Institute of Medical Research (NIMR) of Tanzania; and the Tanzania Commission for Science and Technology (COSTEC).

【 授权许可】

CC BY