Safe Excreta Disposal Research Articles

Latrine Utilization and its Associated Factors in Urban Slums Dwellers of Gondar City, Northwest Ethiopia: A Community-Based Cross-Sectional Study.

Sanitation facilities are critical for interrupting the transmission of feco-oral disease through proper use, not simply their physical presence. Latrine utilization is the actual behavior in a practice of regularly using existing latrines for the safe disposal of excreta. In slum regions of developing nations, such as Ethiopia, poor latrine use is a prevalent concern. As a result, the purpose of this study was to examine the state of latrine utilization and its determinant factors in the urban slums of Gondar City, Northwest Ethiopia. A cross-sectional survey was done in slum regions of Gondar City from March 1 to April 30, 2021, with a total of 422 systematically chosen households. A structured pre-tested questionnaire and on-the-spot observational checklists were used to collect the data from each household. Latrine utilization was observed among 31.5% of households. Latrine utilization was also significantly associated with the age of the latrine (age ⩽10 years) (AOR: 2.31; 95% CI (1.15, 4.63)), cleanliness of the latrine (AOR: 3.70; 95% CI (1.16, 11.78)), pit being lined (AOR: 6.33; 95% CI (2.09, 19.15)), depth of latrine (⩽3 m) (AOR: 0.43; 95% CI (0.24, 0.77)), and cleaning materials for handwashing (AOR: 0.33; 95% CI (0.15, 0.75)). Based on the present finding, most households didn't have proper latrine utilization practices. The age of the latrine, cleanliness of the latrine, pit being lined, depth of the pit, and cleaning materials for handwashing were associated factors of latrine utilization. As a result, sanitation interventions such as health education about improving the cleanliness and sanitary condition of existing latrine facilities and constructing lined and deep new latrines as the goal's standard should be implemented.

Effectiveness of Structured Teaching Programme on Knowledge regarding Helminthic Infestations among Mothers of Under- Five children

Background: Worm infestation is a major public health problem. It has been estimated that more than 25% of the world’s population are infected with worms, with the major incidence occurring in developing countries. Worm infestation can be prevented by practices such as safe disposal of excreta, washing hands after defection, wearing slippers and food hygiene, washing vegetables and fruits properly before using. These can be implemented through effective education of mothers because the mother is only the person who provides the proper education to their children. Objectives: 1. To assesses the existing knowledge regarding helminthic infestations among the mothers of under- five children. 2. To evaluate the effectiveness of structured teaching programme on knowledge regarding helminthic infestation among the mothers of under- five children. 3. To determine the association between pre-test knowledge scores regarding helminthic infestations among the mothers of under five children with selected sample characteristics. Methodology: The research design used for this study was pre experimental, one group pre-test post-test design. The study was conducted at St. Philomena’s hospital in Bengaluru, Karnataka. The sample size selected for this study consists of 30 mothers of under- five children. Non- probability purposive sampling technique was used to select the samples. The tool used in this study was socio-demographic profile and structured knowledge questionnaire. Result: In the pre-test, none had adequate knowledge, whereas 11 (36.6%) samples had moderate knowledge and 19(63.4%) of them had inadequate knowledge. In the post-test, 9(30%) samples had adequate knowledge, whereas 21 (70%) samples had moderate knowledge and none of them had inadequate knowledge. The mean post- test knowledge (24) score was higher than the mean pre-test (12.5). The scores predicted the significant difference (11.5) at p<0.05 level. The calculated “t” value was (14.66) at p <0.05 level of significance, which indicated the significant difference in the level of knowledge before and after the implementation of structured teaching program. Among socio-demographic variables; occupation of mother, type of family and source of information had association with the pre-test knowledge scores of mothers of under- five children. Conclusion: From the findings of the study, it was concluded that the structured teaching programme regarding helminthic infestations was effective in improving the knowledge among the mothers of under- five children.

Factors influencing sustainability of open defecation free (ODF) status in rural India: A cross sectional study

Tackling a simple and sensitive concern of ‘Open Defecation (OD)’ is such a compounded and righteous challenge that enormous efforts and resources are needed to bring in the desired changes in the villages. Towards this, attaining open defecation free (ODF) status by providing toilet facilities to every household is the foremost step in rural sanitation programme under Swachh Bharat Mission – Gramin (SBM –G) being implemented by the Government of India. The present paper aims to examine the factors that have influence in attaining ODF status in rural areas. In this study, various parameters that contribute to attaining ODF status in the villages were identified and an extensive primary survey was conducted in 32,390 households across 686 rural villages in Krishna District of Andhra Pradesh, India. The empirical analysis of the data using a multinomial logistic regression model revealed that the factors such as water availability, safe excreta disposal, technology used for toilet construction and awareness on Swachh Bharat have an influence in achieving the open defecation free status in the villages to a greater extent.

A critical review on sludge management from onsite sanitation systems: A knowledge to be revised in the current situation

Access to safe excreta disposal is a basic human right and an essential element of human development. Developing countries (like India) have constructed millions of toilets with on-site sanitation technologies (OSTs). However, these OSTs lack the required management system for collection, transportation and disposal of Faecal Sludge (FS, sludge getting accumulated in OST), leading to considerable water and soil pollution. The major challenge in FS Management is the collation of scattered data and concentrated experiences (i.e., existing knowledge remains with the practitioners in the field without a written record). Therefore, a critical review of existing knowledge on OST, FS collection, transportation, and its utilisation is essential. This study highlighted shortcomings associated with existing OST, FS collection, transportation, and treatment systems. Furthermore, this study provided a framework for appropriate selection of OST based on available sanitation chains, and a critical analysis of FS characteristics (i.e., total solids, pH, electrical conductivity, biological oxygen demand, chemical oxygen demand, and pathogens of FS ranged from 830 to 72000 mg/L, 6.8 to 7.8, 1.9 to 3.5 mS/cm, 500–5000 mg/L, 100 to 49,000 mg/L, and 106 to 107 E-coli and 103 to 104 parasitic worms per litre of FS, respectively) to design treatment systems for FS utilisation as a resource in agricultural, aqua-culture, and construction application.

Exploring the Use of Cognitive Approach in Mitigating Unsafe Excreta Disposal in Turkana County, Kenya

We evaluated the influence of induced behavioural change on the community to adopt safe excreta disposal practices. This study was informed by unmerited programs which are majorly provided by most of the health organisations providing sanitary facilities rather than effective use which have failed to reduce the persistent occurrence of waterborne epidemics due to unsafe excreta disposal. Information sought in this survey was from two distinct populations of triggered and non-triggered villages of Turkana County, Kenya. Purposive sampling was used in identifying triggered and non-triggered villages, while systematic random sampling was used to administer structured questionnaires to respondents from identified sample units. From analysed data, the results showed latrine users from triggered villages were many compared with non-triggered villages. Again, the variable of education level, which showed to be critical, suggesting to influence latrine use among rural communities irrespective of the triggers. The parameter estimator of public health extension services and information sharing means from the neighbourhood showed to be statistically significant in influencing adoption and diffusion of health knowledge. In conclusion, involving health experts in knowledge diffusion and scaling up formal education among communities influences the adoption of safe excreta disposal practices. The significance of random factor in the OLS model, explains omitted and/or unobserved variables and existences of unclearly explained variables, informs the need for further investigation.

Household latrine utilization and associated factors in semi-urban areas of northeastern Ethiopia.

Latrine utilization is the actual behavior in a practice of regularly using existing latrines for safe disposal of excreta. Latrine utilization is a common problem in semi-urban areas of developing countries, including Ethiopia. Since the status of latrine utilization and associated factors among semi-urban areas of northeastern Ethiopia, including Alansha in South Wollo Zone is unknown, local data is needed in order to assess the need for planning of intervention programs for the improvement of latrine utilization to support consistent and sustained latrine utilization. This study is designed to address this knowledge gap. A cross-sectional study was conducted from February to March, 2019 among 401 systematically selected households. Data were collected by trained workers using a pre-tested, structured questionnaire via face-to-face interviews and on-the-spot observations of the latrines. A systematic random sampling method was used to select participant households. Data were entered using EpiData version 3.1 and exported to Statistical Package for the Social Sciences (SPSS) version 25.0 for data cleaning and analysis. The wealth index status of participants was estimated using principal component analysis. Data were analyzed using a binary logistic regression model at 95% confidence interval (CI). From the multivariable logistic regression analysis, variables with p-value < 0.05 were taken as statistically significant and independently associated with latrine utilization. Model fitness was checked using Hosmer-Lemeshow test. We found that the prevalence of latrine utilization among households was 71.8% (95% CI [67.5-76.1%]) while 28.2% (95% CI [23.9-32.5%]) did not utilize latrines. About one-fifth (21.7%) of participant households were found to have a pit latrine with slab and 78.3% (311) used pit latrines without slab. The hygienic condition of the majority (82.9%) of the latrines was dirty and only 17.1% clean. Household family size from one to three persons (AOR: 3.99, 95% CI [1.20-6.24]), presence of primary or secondary school student in a house (AOR: 2.33, 95% CI [1.42-3.83]), number of years since latrine was constructed (≥ 2 years) (AOR: 1.82, 95% CI [1.12-2.95]) and a frequency of daily cleaning of the latrine (AOR: 2.19, 95% CI [1.12-4.28]) were factors significantly associated with latrine utilization. Seven out of ten households utilized a latrine. Factors significantly associated with latrine utilization were household family size from one to three persons, presence of primary or secondary school student in the house, time since household latrine had been constructed of two or more years and daily frequency of latrine cleaning. Therefore, it is recommended that measures to promote behavioral change towards further improvement in sustainable and consistent latrine utilization should be carried out based on the evidence of the determinant factors found in this study.

Communal latrine utilization and associated factors in Addis Ababa, Ethiopia: a community-based cross-sectional study

Abstract Despite the quick urban population growth increased volume of wastes, including human excreta, which demands an expanded need of infrastructure, solid institutional setup and communities' engagement for management of safe disposal of excreta, arrangement of such basic social services has not developed as per the rate of population growth. Mostly, communal latrines are inclined towards an absence of cleanliness, as they accommodate many people beyond their capacity, filling up septic tanks quickly. A community-based cross-sectional study conducted in 817 randomly selected communal latrine user households, five focus group discussions and four key informant interviews were analysed. Bivariate and multivariate logistic regression analysis was performed to discover the impact of different factors on the use of communal latrines. The findings revealed that the rate of communal latrine use in Addis Ababa was about 79.8%. Unhygienic conditions, latrine emptying challenges, extreme smell, number of family units sharing the same squats, and latrine designs for the aged and children were identified as barriers to latrine utilization. This study suggests that, in parallel with the continued investments to increase access to sanitary facilities in the city, the management and behavioural change part has likewise to be stressed for better use and sustainability.

Understanding the Challenges of Improving Sanitation and Hygiene Outcomes in a Community Based Intervention: A Cross-Sectional Study in Rural Tanzania.

Good sanitation and clean water are basic human rights yet they remain elusive to many rural communities in Sub-Saharan Africa (SSA). We carried out a cross sectional study to examine the impact of a four-year intervention aimed at improving access to water and sanitation and reducing waterborne disease, especially diarrhea in children under five years old. The study was carried out in April and May 2015 in Busangi, Chela and Ntobo wards of Kahama District of Tanzania. The interventions included education campaigns and improved water supply, and sanitation. The percentage of households (HHs) with access to water within 30 min increased from 19.2 to 48.9 and 17.6 to 27.3 in the wet and dry seasons, respectively. The percentage of HHs with hand washing facilities at the latrine increased from 0% to 13.2%. However, the incidence of diarrhea among children under five years increased over the intervention period, RR 2.91 95% CI 2.71–3.11, p < 0.0001. Availability of water alone may not influence the incidence of waterborne diseases. Factors such as water storage and usage, safe excreta disposal and other hygiene practices are critical for interventions negating the spread of water borne diseases. A model that articulates the extent to which these factors are helpful for such interventions should be explored.

The Impact of Drinking Water Quality and Sanitation Behavior on Child Health: Evidence from Rural Ethiopia

This paper examines the impact of drinking water quality and sanitation behavior on child health in rural districts of Ethiopia. Using primary household survey data and microbiological water test for Escherichia coli, we use various estimation methods to quantify the impacts of water quality and sanitation behavior on diarrhea incidence among children under five years old. Our results show that uncontaminated household storage water and safe child stool disposal decrease incidence of child diarrhea by 16% and 23% respectively. In contrast, neighborhood concentration of pit latrine increases incidence of child diarrhea by 12%. The latter result casts serious doubt on the assumed health and social benefits of moving from open to fixed-location defecation. Creating open defecation free communities in rural areas is not enough to achieve the desired health benefits of sanitation. To protect rural households from the risk of contracting communicable diseases, existing pit latrines should be upgraded to make them safer to use – fly-proofed and hygienic. There is a need for appropriate policy actions to improve household drinking water quality and to change people’s behavior towards safe sanitation practices. Increasing access to clean water supply and providing means for safe excreta disposal will bring significant health and social gains. Moreover, promotion of hygiene education campaigns about household water treatment, safe water storage and handling, washing hands with soaps at critical times, and adequately removing child feces from the domestic environment can also help ensure that people preserve good health in their household and their community.

A Case Study of Excreta Disposal Following the 2006 Java Earthquake*

Providing safe excreta disposal following disasters is important for disease prevention and the safety and dignity of the affected population. This is challenging because every emergency varies due to the nature of the disaster, local conditions and the characteristics of the affected population. This paper investigates the impact of the 2006 Java earthquake on excreta disposal needs and the response to those needs. Relevant documents were retrieved from the ReliefWeb database, complemented by a literature search. The case study highlights gaps in rapidly providing latrines on a large scale. Three months after the disaster, only 57% of the latrines targeted had been provided. One way to address this problem is to better understand the factors affecting excreta disposal needs and response, allowing appropriate solutions to be identified more effectively.

Elimination of Pollution of Groundwater by On-Site Sanitation Systems

About half the population in developing countries lack safe excreta disposal facilities. Improper wastewater disposal contaminates groundwater resulting in spread of water related diseases such as typhoid, cholera, dysentery. This research experimentally tested the applicability of charcoal and saw dust packed membranes as sewage purifiers for on-site sanitation systems like, septic tanks, cesspool, pit latrines, pour-flush pit excreta systems. Tests for E. coli, COD and BOD of the influent which was raw sewerage from sewers and effluent from layered saw dust and charcoal purifying materials experimental setup were separately carried out. The layers were varied from 150 mm, 200 mm and 300 mm with 150 mm layers of gravel in between. The experimental tests showed that 300 mm charcoal layers with a 150 mm gravel middle layer, reduced E. coli from 4800×1014 CFU/100ml to 1.08×104 CFU/100ml, BOD5 from 698 mg/l to 0.5 mg/l, COD from 1492 mg/l to 3.0 mg/l against environmental standards of 1.0×104 CFU/100ml, 50 mg/l, and 100 mg/l respectively and its efficiency is directly proportional to thickness of charcoal dust layers. In conclusion, introducing a lined purification chamber with layers of charcoal dust between the on-site sanitation system and soak pit will eliminate the pollution of ground water.

Water, sanitation, and hygiene in emergencies: summary review and recommendations for further research

Water, sanitation, and hygiene interventions can interrupt diarrhoeal disease transmission and reduce the burden of morbidity and mortality associated with faecal-oral infections. We know that rapid response of effective WASH infrastructure and services can prevent or lessen the impact of diarrhoeal outbreaks that can exacerbate the human suffering accompanying humanitarian crises. In this review summary, we present an overview of current knowledge about what works to prevent disease in emergency WASH response. We know that providing safe water, safe excreta disposal, and basic hygiene measures such as hand washing with soap are effective interventions both within emergency settings as well as in longer-term development, but innovation and further research are needed to make WASH response more effective. We propose key areas for critical research to support the evidence base for WASH interventions in emergencies and promote innovation.

Access to, and Utilization of Information on Sanitation and Hygiene by Rural Households in Alaba Special District, Southern Ethiopia

The main objective of this study was assessing the level of sanitation and hygiene information and identifying factors that determine its access and utilization by rural households in Alaba District, Southern Ethiopia. The study generated the required data from 162 respondents selected from four rural 'kebeles'/villages using multistage sampling technique. Both qualitative and quantitative data were collected, and then the data were analyzed using descriptive statistics and Ordered Logit Model. The analysis revealed that rural households in the study area have limited access to sanitation and hygiene information. Taking selected indicators of sanitation and hygiene: once in a week basis, 3.1% of the respondents accessed the messages on hand washing which is followed by safe excreta disposal (1.9%), safe water collection and storage (1.2%), food hygiene (0.6%), household waste disposal (0.6%) and disease causing vectors (0%). With regard to utilization of the accessed informa- tion, safe excreta disposal accounts for (57.4%), hand washing (26.5%), safe water collection and storage (16%), disease causing vectors (9.3%), food hygiene (4.3%), and household waste disposal (3.1%). The Ordered Logit regression result indicated that educational status of the respondent, health extension worker contact, information seeking behavior and percep- tion of the respondent were found to be significant determinants of access to sanitation and hygiene information among rural households in the study area. Regarding sanitation and hygiene information utilization, the analysis of Ordered Logit showed that educational status of the respondent, contact with health extension worker and knowledge level significantly affect the utilization decision of sanitation and hygiene information accessed by rural households. The overall findings of the study underlined the importance of communication and behavioral factors in the areas of sanitation and hygiene information access and level of utilization. Therefore, policy and health interventions should give emphasis to improvement of information sources, which can address the rural households and more focuses should be given to adult education and behavioral change communi- cation approaches. 1. BACKGROUND

Excreta disposal in emergencies: Bag and Peepoo trials with internally displaced people in Port-au-Prince

After a series of earthquakes devastated Port-au-Prince, Haiti, on 12 January 2010, safe excreta disposal became an urgent priority. To mainstream innovative approaches to sanitation within the realities of urban humanitarian response, Oxfam GB undertook a trial from April to May 2010, of standard bag and Peepoo excreta disposal systems in two IDP settlements. Trial results demonstrate that with proper collection and removal, both bags and Peepoos are viable excreta disposal options in emergencies. A reduction was seen in ‘flying toilets’, open defecation and user reports on diarrhoea in both settlements. For in-home use, the Peepoo was preferred over bags, 84 per cent to 55 per cent (χ2 = 6.15, p=0.013) based on its ability to contain odour. Key programmatic recommendations include contingency planning for disaster-prone areas and further analysis of cost effectiveness and phase-out points for bag excreta disposal systems. Additionally, the Peepoo size should be adjusted to be more widely applicable in diverse emergency settings.

Issues related to sanitation failure in India and future perspective

Dear Sir, The October 2008 issue of the journal discussed facts concerning NFHS-3 on sanitation failure.[1] The ignored aspect of environmental sanitation in India highlighting legal regulations for its correction was discussed in the Jan 2008 issue.[2] Millennium Development Goals (MDGs) define improved sanitation as “connection to a public sewer, connection to a public system, pour flush latrine, simple pit latrine or ventilated improved pit latrine. The excreta disposal system is considered adequate if it is private or shared (but not public), and if it hygienically separates human excreta from human contact”.[3] The sanitation sector is in a crisis with 40% of the world's population lacking access to even basic sanitation. Behavioral change is the critical component required to improve sanitation. It is when people use a latrine, rather than when one is constructed, that the wider benefits are realized. Similarly, it applies for practicing other aspects of cleanliness like hand washing, drinking water and eating food. A systematic review estimated that the safe disposal of excreta alone can reduce diarrheal disease by 36%[4] and a separate review of hand washing with soap on diarrhea found a 45% reduction.[5] Also it was found that sanitation could prevent childhood mortality from pneumonia and malnutrition besides diarrhea. Political will and commitment is also required urgently to tackle the crisis. Low political priority plays out in chronic under investment which leads to adverse effects of poor sanitation. Although sanitation is the single most cost effective intervention most governments, including donors, do not count what they are spending on. The allocation of central government budgetary allocation for health sector out of the total budget remains stagnant at 1.3% of Gross Domestic Product (GDP). Besides, this proportion has progressively declined from seven to 5.5% in the States. Water supply and sanitation is one of the seven sub sectors in the health sector as given by Planning Commission of India.[3] Sanitation is interlinked and interdependent on other essential health sub sectors such as medical education, training and research, public health services and control of communicable diseases and underpins all development efforts. In a country with 35% illiterate population, effective communication of public health related issues like sanitation is a big challenge. Besides mass media, there is a need for involvement of NGOs and community based organizations and the community to tackle the crisis of sanitation failure. Decentralized management of primary health care level is strongly advocated through Panchayati Raj Institutions (PRIs) as recommended by National Health Policy 2002. The policy also recommends convergence of management of all vertical public health programs at district level and below. However, before delegation of the responsibility and devolution of financial and administrative powers to PRIs it is essential to build capacities through interactive training sessions. Simultaneously, health functionaries also need to be oriented to adjust to a new environment and play their effective roles.[6] Thus, improvement in sanitation requires newer strategies and targeted interventions with follow-up evaluation. The goals on environmental sustainability set by MDG, by 2015, seem to be unrealistic.

Hepatitis E, Central African Republic

Hepatitis E, Central African Republic

Prevalence of soil transmitted helminthes infections among Bangladeshi males seeking job abroad

This cross-sectional study was undertaken to identify the prevalence of soil transmitted helminthes infections and its relation to socio-demographic characteristics among Bangladeshi males seeking job abroad. The stool sample of each respondent coming for medical check up was collected by code number and examined under microscope to see the presence helminthic ova or larvae. Among 8140 respondents, 68.05% were from rural and 31.95% from urban area. As a whole, helminthic infection was found in 20.22% respondents. Off which rural and urban distribution were 27.58% and 5.22% respectively (p<0.001). Pattern of helminthes as per rural and urban basis were as follows: Ascaris lumbricoides in 12.45% & 2.61%, Trichuris trichurias in 2.61% & 2.50% samples respectively. As per age distribution was concerned, number of positive cases among rural population in all age groups was statistically higher (p<0.001) than that of urban population. Similarly, rate of combined infections among the rural population was also statistically higher (p<0.001). Higher positivity of helminthes was obtained in low-level educated respondents and in the farmers group. Since the study reflected a high proportion of helminthes infections in rural people, so it was recommended to launch regular deworming programme in rural community at national level. Health education activities on proper sanitary practice, safe disposal of excreta and taking safe food-drinks should be meaningful to eradicating helminthes infections. Further study is needed for monitoring the active status in the community.

Field survey on water supply, sanitation and associated health impacts in urban poor communities - a case from Mumbai City, India

A field survey was conducted on four slum, squatter and pavement dweller communities of Mumbai City, India with a total sample size of 1,070 households. Study revealed extremely low water consumption pattern averaging merely 30 l/c x d, no sewerage and safe excreta disposal facilities manifested by high occurrence of water-borne diseases. The annual diarrhoeal, typhoid and malaria cases were estimated to 614, 68 and 126 per thousand populations respectively. At point prevalence scale, at least 30% of all morbidity can be accounted for by water-related infections. In addition to the impacts of neighborhood water pollution and sanitation, such diseases were also found positively correlated with low water consumption and poverty related factors as, poor housing and family income. Analysis of variance also revealed intra-poor gradient both in living standards and health conditions on which the pavement dwellers were observed to be the greatest sufferers of all.

Excreta Disposal Behaviour and Latrine Ownership in Relation to the Risk of Childhood Diarrhoea in Sri Lanka

A case-control study of environmental and behavioural risk factors for childhood diarrhoea was conducted in Kurunegala district, Sri Lanka. From five hospitals, 2458 children aged less than 5 years and suffering from diarrhoea were recruited as clinic cases, and a further 4140 reporting with complaints other than diarrhoea were recruited as clinic controls. Community-based cross-sectional surveys were also conducted in three of the five areas served by these hospitals, and from these a further 1659 children were recruited as community controls. Children from households where excreta were reported to be disposed of in a latrine were less likely to have diarrhoea than children whose families improperly disposed of excreta. The results obtained from comparisons of cases with clinic controls (adjusted odds ratio [OR] 1.42, 95% confidence interval [CI] : 1.01-1.98), and of cases with community controls (OR 1.35, 95% CI : 0.85-2.13) were in agreement, suggesting that no important selection bias operated on this association. If the observed proportion (91%) of improper excreta disposal among the population could be reduced to 50%, 12% of childhood diarrhoea episodes would be prevented. Although latrine ownership may be a necessary condition for safe excreta disposal behaviour, diarrhoeal morbidity may only be reduced in Sri Lanka if behavioural changes take place concomitant with the construction of sanitation facilities.

Selective primary health care: strategies for control of disease in the developing world. XII. Ascariasis and trichuriasis.

Ascariasis and trichuriasis are the most prevalent and widespread intestinal helminthiases. Transmission of disease occurs by ingestion or inhalation of Ascaris and Trichuris eggs embryonated in the soil. During the migration of Ascaris to the lungs, pneumonic symptoms may develop. The intestinal stage of the parasite can cause severe symptoms and complications when the worm burden is high. High numbers of Trichuris may cause diarrhea. The poor standard of hygiene, the biology of the parasite (which is such that a high number of very resistant eggs are produced), and the habits of the host (such as the use of night soil) are factors causing a high prevalence of infection in many countries in Asia, Africa, South America, and Europe. The mechanism of the transmission of Ascaris varies in different communities. The peak of infection is among children aged four to 14 years. Worm burden is normally low, and only a small segment of the population harbors a high proportion of the worms present in a community. Control of infections due to Ascaris and Trichuris is feasible by a combination of mass chemotherapy with the effective drugs now available, safe disposal of excreta, destruction of the eggs, and health education.