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INTRODUCTION
Adequate sanitation is an important foundation for health, economic development and well-being (Bartram & Cairncross 2010). In low- and middle-income countries, most urban dwellers (>70%) use mainly on-site sanitation systems such as pit latrines, public toilets and septic tanks for excreta and wastewater disposal (Tilley et al. 2014). In areas where access to sustainable sanitation, i.e., safe storage, collection, treatment and safe disposal/reuse of faeces and urine is insufficient or poor, parasites spread in the natural environment (Bartram & Cairncross 2010). Lack of sanitation leads to several diseases, and diseases associated with poor sanitation are particularly correlated with poverty and are responsible for about 10% of the global burden of diseases. In fact, about half the urban population of Africa have diseases associated with poor sanitation, hygiene and water (Wolf et al. 2014). It has been stated that 1 g of fresh excreta from an infected person can contain around 106 viral pathogens, 106-108 bacterial pathogens, 104 protozoans cysts or oocysts and 10-104 helminth eggs. The geohelminth Ascaris lumbricoides is a global health concern because it infected nearly 800 million people in 2010, especially in tropical and subtropical regions (Pullan et al. 2014). The negative health outcomes of these infections are numerous and include morbidity due to nutritional impairment, negative impact on child growth, cognitive development and worker productivity (Bethony et al. 2006). Helminth infections are acquired from an environment contaminated by worms' infective stages that developed from their fertilized eggs (Pullan et al. 2014). People infected with helminths pass eggs in their faeces, which will then mature in the environment before becoming infective again. Thus, the storage practice of human excreta is an important factor to reduce the risk of infections with helminths (Yen-Phi et al. 2010; Stenström et al. 2011).
The survival of parasites outside the host depends on environmental conditions. There are many abiotic and biotic factors, such as temperature, which affect resistant stages of parasite eggs (Manser et al. 2015). Pecson et al. (2007) revealed that there are some factors that may contribute to the survival of Ascaris eggs in sewage sludge including temperature and pH. Another chemical factor known to affect the survival of helminth eggs is ammonia. It was shown that an increase of the pH may be...