Geospatial Analysis of Neglected Tropical Diseases in Southern Tanzania

Background: Neglected tropical diseases (NTDs) such as schistosomiasis and soil-transmitted helminthiases (STHs) constitute major public health problems in Tanzania. However, current information on the magnitude and distribution of these diseases at focal level is lacking, particularly for marginal areas, and this is a setback to their control.

Aim: Open Source Geographical Information System was used to map risk factors for schistosomiasis and soil-transmitted helminthiases in Mtwara and Lindi Districts.  

Methods: Stool and urine samples were obtained from 1750 residents of 19 villages between April and October 2016. Filtration technique was used to examine schitsosomes and Kato Katz for soil-transmitted helminths.  GPS coordinates for households and water bodies were captured to establish their spatial relationships with human residence and associated risks for schistosomiasis. A questionnaire was used to obtain information on risk behaviour and activities exposing people to infectious diseases.  

Results: Hookworm and Schistosoma haematobium were the most common parasites. T. trichuris and Taenia spp. infections showed no pattern across study villages.  Ngorongoro village had the largest number of people infected with S. haematobium in the wet season and dry season.  S. haematobium prevalence differed significantly between villages (p=0.035). Parasite prevalence in relation to participants’ sex, education level, presence or absence of rice farming, or whether drinking water was treated or not did not show significance (p > 0.05). 

Conclusion: The risk of acquiring hookworm or urinary schistosomiasis in these areas depended on one’s age and place of residence.  Infection prevalence aggregated at the village level and visualised as choropleth distribution maps indicated site-related transmissions.  This information is useful in guiding control efforts against schistosomiasis and other helminths in these areas through judicial allocation of resources.  

Key words: Geospatial analysis, Schistosoma haematobium, hookworm, Southern Tanzania.

Title: Geospatial Analysis of Neglected Tropical Diseases in Southern Tanzania

Jared Bakuza¹ *, Emiliana Mwita² Grades Stanley³

¹Department of Biological Sciences, Dar es Salaam University College of Education, Tanzania

²Geography and Economics Department, Dar es Salaam University College of Education, Tanzania

³GIS Unit, National Institute for Medical Research, Dar es Salaam Tanzania

* Corresponding author: bakuzajared@yahoo.co.uk