[Show abstract][Hide abstract] ABSTRACT: Soil-transmitted helminths (STH) - a class of parasites that affect billions of people - can be mitigated using mass drug administration, though reinfection following treatment occurs within a few months. Improvements to water, sanitation and hygiene (WASH) likely provide sustained benefit, but few rigorous studies have evaluated the specific WASH components most influential in reducing infection. There is a need for alternative analytic approaches to help identify, characterize and further refine the WASH components that are most important to STH reinfection. Traditional epidemiological approaches are not well-suited for assessing the complex and highly correlated relationships commonly seen in WASH.
[Show abstract][Hide abstract] ABSTRACT: Preventive chemotherapy represents a powerful but short-term control strategy for soil-transmitted helminthiasis. Since humans are often re-infected rapidly, long-term solutions require improvements in water, sanitation, and hygiene (WASH). The purpose of this study was to quantitatively summarize the relationship between WASH access or practices and soil-transmitted helminth (STH) infection.
We conducted a systematic review and meta-analysis to examine the associations of improved WASH on infection with STH (Ascaris lumbricoides, Trichuris trichiura, hookworm [Ancylostoma duodenale and Necator americanus], and Strongyloides stercoralis). PubMed, Embase, Web of Science, and LILACS were searched from inception to October 28, 2013 with no language restrictions. Studies were eligible for inclusion if they provided an estimate for the effect of WASH access or practices on STH infection. We assessed the quality of published studies with the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach. A total of 94 studies met our eligibility criteria; five were randomized controlled trials, whilst most others were cross-sectional studies. We used random-effects meta-analyses and analyzed only adjusted estimates to help account for heterogeneity and potential confounding respectively. Use of treated water was associated with lower odds of STH infection (odds ratio [OR] 0.46, 95% CI 0.36-0.60). Piped water access was associated with lower odds of A. lumbricoides (OR 0.40, 95% CI 0.39-0.41) and T. trichiura infection (OR 0.57, 95% CI 0.45-0.72), but not any STH infection (OR 0.93, 95% CI 0.28-3.11). Access to sanitation was associated with decreased likelihood of infection with any STH (OR 0.66, 95% CI 0.57-0.76), T. trichiura (OR 0.61, 95% CI 0.50-0.74), and A. lumbricoides (OR 0.62, 95% CI 0.44-0.88), but not with hookworm infection (OR 0.80, 95% CI 0.61-1.06). Wearing shoes was associated with reduced odds of hookworm infection (OR 0.29, 95% CI 0.18-0.47) and infection with any STH (OR 0.30, 95% CI 0.11-0.83). Handwashing, both before eating (OR 0.38, 95% CI 0.26-0.55) and after defecating (OR 0.45, 95% CI 0.35-0.58), was associated with lower odds of A. lumbricoides infection. Soap use or availability was significantly associated with lower infection with any STH (OR 0.53, 95% CI 0.29-0.98), as was handwashing after defecation (OR 0.47, 95% CI 0.24-0.90). Observational evidence constituted the majority of included literature, which limits any attempt to make causal inferences. Due to underlying heterogeneity across observational studies, the meta-analysis results reflect an average of many potentially distinct effects, not an average of one specific exposure-outcome relationship.
WASH access and practices are generally associated with reduced odds of STH infection. Pooled estimates from all meta-analyses, except for two, indicated at least a 33% reduction in odds of infection associated with individual WASH practices or access. Although most WASH interventions for STH have focused on sanitation, access to water and hygiene also appear to significantly reduce odds of infection. Overall quality of evidence was low due to the preponderance of observational studies, though recent randomized controlled trials have further underscored the benefit of handwashing interventions. Limited use of the Joint Monitoring Program's standardized water and sanitation definitions in the literature restricted efforts to generalize across studies. While further research is warranted to determine the magnitude of benefit from WASH interventions for STH control, these results call for multi-sectoral, integrated intervention packages that are tailored to social-ecological contexts. Please see later in the article for the Editors' Summary.
PLoS Medicine 03/2014; 11(3):e1001620. · 15.25 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Mass drug administration (MDA) for lymphatic filariasis (LF) programs has delivered more than 2 billion treatments of albendazole, in combination with either ivermectin or diethylcarbamazine, to communities co-endemic for soil-transmitted helminthiasis (STH), reducing the prevalence of both diseases. A transmission assessment survey (TAS) is recommended to determine if MDA for LF can be stopped within an evaluation unit (EU) after at least five rounds of annual treatment. The TAS also provides an opportunity to simultaneously assess the impact of these MDAs on STH and to determine the frequency of school-based MDA for STH after community-wide MDA is no longer needed for LF.
Pilot studies conducted in Benin and Tonga assessed the feasibility of a coordinated approach. Of the schools (clusters) selected for a TAS in each EU, a subset of 5 schools per STH ecological zone was randomly selected, according to World Health Organization (WHO) guidelines, for the coordinated survey. In Benin, 519 children were sampled in 5 schools and 22 (4.2%) had STH infection (A. lumbricoides, T. trichiura, or hookworm) detected using the Kato-Katz method. All infections were classified as light intensity under WHO criteria. In Tonga, 10 schools were chosen for the coordinated TAS and STH survey covering two ecological zones; 32 of 232 (13.8%) children were infected in Tongatapu and 82 of 320 (25.6%) in Vava'u and Ha'apai. All infections were light-intensity with the exception of one with moderate-intensity T. trichiura.
Synchronous assessment of STH with TAS is feasible and provides a well-timed evaluation of infection prevalence to guide ongoing treatment decisions at a time when MDA for LF may be stopped. The coordinated field experiences in both countries also suggest potential time and cost savings. Refinement of a coordinated TAS and STH sampling methodology should be pursued, along with further validation of alternative quantitative diagnostic tests for STH that can be used with preserved stool specimens.
[Show abstract][Hide abstract] ABSTRACT: Trachoma is the world's leading cause of infectious blindness. The World Health Organization (WHO) has endorsed the SAFE strategy in order to eliminate blindness due to trachoma by 2020 through "surgery," "antibiotics," "facial cleanliness," and "environmental improvement." While the S and A components have been widely implemented, evidence and specific targets are lacking for the F and E components, of which water, sanitation, and hygiene (WASH) are critical elements. Data on the impact of WASH on trachoma are needed to support policy and program recommendations. Our objective was to systematically review the literature and conduct meta-analyses where possible to report the effects of WASH conditions on trachoma and identify research gaps.
We systematically searched PubMed, Embase, ISI Web of Knowledge, MedCarib, Lilacs, REPIDISCA, DESASTRES, and African Index Medicus databases through October 27, 2013 with no restrictions on language or year of publication. Studies were eligible for inclusion if they reported a measure of the effect of WASH on trachoma, either active disease indicated by observed signs of trachomatous inflammation or Chlamydia trachomatis infection diagnosed using PCR. We identified 86 studies that reported a measure of the effect of WASH on trachoma. To evaluate study quality, we developed a set of criteria derived from the GRADE methodology. Publication bias was assessed using funnel plots. If three or more studies reported measures of effect for a comparable WASH exposure and trachoma outcome, we conducted a random-effects meta-analysis. We conducted 15 meta-analyses for specific exposure-outcome pairs. Access to sanitation was associated with lower trachoma as measured by the presence of trachomatous inflammation-follicular or trachomatous inflammation-intense (TF/TI) (odds ratio [OR] 0.85, 95% CI 0.75-0.95) and C. trachomatis infection (OR 0.67, 95% CI 0.55-0.78). Having a clean face was significantly associated with reduced odds of TF/TI (OR 0.42, 95% CI 0.32-0.52), as were facial cleanliness indicators lack of ocular discharge (OR 0.42, 95% CI 0.23-0.61) and lack of nasal discharge (OR 0.62, 95% CI 0.52-0.72). Facial cleanliness indicators were also associated with reduced odds of C. trachomatis infection: lack of ocular discharge (OR 0.40, 95% CI 0.31-0.49) and lack of nasal discharge (OR 0.56, 95% CI 0.37-0.76). Other hygiene factors found to be significantly associated with reduced TF/TI included face washing at least once daily (OR 0.76, 95% CI 0.57-0.96), face washing at least twice daily (OR 0.85, 95% CI 0.80-0.90), soap use (OR 0.76, 95% CI 0.59-0.93), towel use (OR 0.65, 95% CI 0.53-0.78), and daily bathing practices (OR 0.76, 95% CI 0.53-0.99). Living within 1 km of a water source was not found to be significantly associated with TF/TI or C. trachomatis infection, and the use of sanitation facilities was not found to be significantly associated with TF/TI.
We found strong evidence to support F and E components of the SAFE strategy. Though limitations included moderate to high heterogenity, low study quality, and the lack of standard definitions, these findings support the importance of WASH in trachoma elimination strategies and the need for the development of standardized approaches to measuring WASH in trachoma control programs. Please see later in the article for the Editors' Summary.
PLoS Medicine 02/2014; 11(2):e1001605. · 15.25 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We conducted a longitudinal analysis of 117 lymphedema patients in a filariasis-endemic area of Haiti during 1995-2008. No difference in lymphedema progression between those who received or did not receive mass drug administration (MDA) was found on measures of foot (P = 0.24), ankle (P = 0.87), or leg (P = 0.46) circumference; leg volume displacement (P = 0.09), lymphedema stage (P = 0.93), or frequency of adenolymphangitis (ADL) episodes (P = 0.57). Rates of ADL per year were greater after initiation of MDA among both groups (P < 0.01). Nevertheless, patients who received MDA reported improvement in four areas of lymphedema-related quality of life (P ≤ 0.01). Decreases in foot and ankle circumference and ADL episodes were observed during the 1995-1998 lymphedema management study (P ≤ 0.01). This study represents the first longitudinal, quantitative, leg-specific analysis examining the clinical effect of diethylcarbamazine on lymphedema progression and ADL episodes.
The American journal of tropical medicine and hygiene 11/2013; · 2.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Improvements of water, sanitation, and hygiene (WASH) infrastructure and appropriate health-seeking behavior are necessary for achieving sustained control, elimination, or eradication of many neglected tropical diseases (NTDs). Indeed, the global strategies to fight NTDs include provision of WASH, but few programs have specific WASH targets and approaches. Collaboration between disease control programs and stakeholders in WASH is a critical next step. A group of stakeholders from the NTD control, child health, and WASH sectors convened in late 2012 to discuss opportunities for, and barriers to, collaboration. The group agreed on a common vision, namely "Disease-free communities that have adequate and equitable access to water and sanitation, and that practice good hygiene." Four key areas of collaboration were identified, including (i) advocacy, policy, and communication; (ii) capacity building and training; (iii) mapping, data collection, and monitoring; and (iv) research. We discuss strategic opportunities and ways forward for enhanced collaboration between the WASH and the NTD sectors.
[Show abstract][Hide abstract] ABSTRACT: In areas endemic for lymphatic filariasis, progression of lymphoedema is associated with recurrent bacterial acute dermatolymphangioadenitis (ADLA). The role of antibacterial soap in preventing ADLA is unknown. In a randomized double-blinded clinical trial in Leogane, Haiti, lymphoedema patients washed affected legs with antibacterial (n = 97) or plain soap (n = 100). Reported ADLA incidence (by recall) before the study was 1.1 episodes per person-year, compared to 0.40 assessed during the 12-month study. ADLA incidence was significantly associated with age, illiteracy and lymphoedema stage, but not with soap type. Washing with soap, regardless of its antibacterial content, can help decrease ADLA incidence. (ClinicalTrials.gov identifier number NCT00139100.).
Transactions of the Royal Society of Tropical Medicine and Hygiene 01/2011; 105(1):58-60. · 1.82 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Approximately 14 million persons living in areas endemic for lymphatic filariasis have lymphedema of the leg. Clinical studies indicate that repeated episodes of bacterial acute dermatolymphangioadenitis (ADLA) lead to progression of lymphedema and that basic lymphedema management, which emphasizes hygiene, skin care, exercise, and leg elevation, can reduce ADLA frequency. However, few studies have prospectively evaluated the effectiveness of basic lymphedema management or assessed the role of compressive bandaging for lymphedema in resource-poor settings.
Between 1995 and 1998, we prospectively monitored ADLA incidence and leg volume in 175 persons with lymphedema of the leg who enrolled in a lymphedema clinic in Leogane, Haiti, an area endemic for Wuchereria bancrofti. During the first phase of the study, when a major focus of the program was to reduce leg volume using compression bandages, ADLA incidence was 1.56 episodes per person-year. After March 1997, when hygiene and skin care were systematically emphasized and bandaging discouraged, ADLA incidence decreased to 0.48 episodes per person-year (P<0.0001). ADLA incidence was significantly associated with leg volume, stage of lymphedema, illiteracy, and use of compression bandages. Leg volume decreased in 78% of patients; over the entire study period, this reduction was statistically significant only for legs with stage 2 lymphedema (P = 0.01).
Basic lymphedema management, which emphasized hygiene and self-care, was associated with a 69% reduction in ADLA incidence. Use of compression bandages in this setting was associated with an increased risk of ADLA. Basic lymphedema management is feasible and effective in resource-limited areas that are endemic for lymphatic filariasis.
[Show abstract][Hide abstract] ABSTRACT: People fearful of being stigmatized by a health-related condition often do not embrace prevention behaviors or seek medical help. They may adhere poorly to treatment regimes for disease and abruptly terminate much needed treatment. Globally, 120 million--many poor women--suffer consequences of lymphatic filariasis that include stigmatizing lymphedema or elephantiasis of the leg. We investigated how women with lymphedema from two different cultures experience stigma and its consequences. Our qualitative data were collected from 56 Dominican women and 48 Ghanaian women with lymphedema. A lymphedema-related stigma framework was developed from constructs derived from the literature and emergent themes from the data. Women described a spectrum of enacted, perceived, and internalized stigma experiences, such as being criticized and isolated by the community, health providers, and even by friends and relatives; they were often denied access to education and meaningful work roles. Some antecedents, consequences, coping strategies, and outcomes of these experiences varied across cultures, with Dominican women faring somewhat better than Ghanaians. Poverty, poor access to health care resources, limited education, and diminished social support challenged the coping strategies of many women and exacerbated negative consequences of lymphedema-related stigma.
Social Science [?] Medicine 12/2008; 68(1):30-8. · 2.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The psychological states of Dominican women with chronic lymphedema and elephantiasis of the leg and the coping strategies they used to ameliorate the negative psychological effects of this condition were explored using modified precepts of grounded theory method. Qualitative data were gathered through in-depth interviewing and focus group discussions held in the Dominican Republic. Thematic results found that compounding their physical disfigurement, functional limitations, and social losses were feelings of depression, embarrassment, social isolation, and despair. Adaptive problem solving and emotion-focused coping strategies that emerged during analysis also are discussed. It is recommended that management of psychological distress should be a significant component of lymphedema management programs in developing countries.
Health Care For Women International 05/2008; 29(4):349-65. · 0.63 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The sex ratio of adult Wuchereria bancrofti from 172 histologically diagnosed cases of lymphatic filariasis, all from an endemic area of Recife, in north-eastern Brazil, was investigated. Of 172 tissue specimens examined, 74 (43%) were lymph nodes and 98 (57%) lymphatic-vessel segments. The morphology of the worms was generally disrupted, in some cases to the point where the worms were almost completely absorbed by the granulomatous inflammatory response. Parasite gender was clearly determined in only 110 (64%) specimens, 61 (55.5 %) of which were lymph nodes and 49 (44.5%) lymphatic vessels. Eighty-seven (79.1%) of these tissue specimens contained only female worms, 17 (14.5%) both males and females, and six only males, giving an overall female:male 'specimen' ratio of 4.5:1. Of the 63 tissue specimens in which dead or degenerating worms were noted, 60 (92.2%) contained only females. All the female worms detected were gravid, regardless of whether male worms were present in the specimen. The implications of these findings for parasite dynamics, the pathogenesis of bancroftian filariasis and the interpretation of ultrasound images of living adult worms are discussed.
Annals of Tropical Medicine and Parasitology 05/2008; 102(3):229-38. · 1.31 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The global strategy for the elimination of lymphatic filariasis (LF) is based on annual mass drug administration (MDA) to interrupt transmission. Noncompliance with MDA represents a serious programmatic obstacle for the LF program because systematically noncompliant individuals may serve as a reservoir for the parasite and permit recrudescence of infection. Using a survey questionnaire concerning practices, beliefs, and attitudes towards MDA, we assessed differences between noncompliant individuals and compliant individuals in Leogane, Haiti (n = 367) after four years of treatment. A logistic regression model showed the odds of being noncompliant were significantly increased for women (odds ratio = 2.74, 95% confidence interval = 1.12-6.70), as well as for people who lacked knowledge about both LF and programs to eliminate infection. Public health programs should be designed to target people who are at risk for systematic noncompliance.
The American journal of tropical medicine and hygiene 03/2008; 78(2):283-8. · 2.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Analysis of clustered data focusing on inference of the marginal distribution may be problematic when the risk of the outcome is related to the cluster size, termed as informative cluster size. In the absence of censoring, Hoffman et al. proposed a within-cluster resampling method, which is asymptotically equivalent to a weighted generalized estimating equations score equation. We investigate the estimation of the marginal distribution for multivariate survival data with informative cluster size using cluster-weighted Weibull and Cox proportional hazards models. The cluster-weighted Cox model can be implemented using standard software. Simulation results demonstrate that the proposed methods produce unbiased parameter estimation in the presence of informative cluster size. To illustrate the proposed approach, we analyze survival data from a lymphatic filariasis study in Recife, Brazil.
Statistics in Medicine 03/2008; 27(4):543-55. · 2.04 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The objectives of this paper were to identify specific factors associated with intact or disrupted social connectedness among Dominican women with chronic filarial lymphedema and better understand the impact of disrupted connectedness on their lives.
Data were collected through 28 individual interviews and 3 focus group discussions of 28 women from filariasis-endemic areas of the Dominican Republic presenting with lymphedema of one or both legs.
The confluence of chronic and acute stressors with severity of lymphedema lead women to rely on others for social support. Women described complications of aging, disability, reduced social networks, and inability to adhere to cultural scripts as contributing to disrupted social connectedness.
Social disconnectedness appears to exacerbate the negative consequences of living with lymphedema among women. Social connectedness and cultural scripts often define a social role for women that transcend physical deformity and disability, while disrupted social connectedness contributes to social isolation, depressive symptoms, and poor health outcomes.
Further behavioral research into the contribution of intact social connectedness to resiliency and coping is warranted in order to develop effective interventions for women. Identifying women with disrupted social connectedness and engaging them in behavioral interventions to enhance natural social networks and create new or enhanced social support opportunities may mitigate the negative effects of social disconnectedness and improve quality of life.
Patient Education and Counseling 12/2007; 68(3):279-86. · 2.60 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To date, few studies have addressed the sequelae of lymphatic filariasis, a mosquito-transmitted disease, on the quality of life of affected women in the Americas. In this qualitative study, we conducted 28 semi-structured interviews and 3 focus groups of women with lymphedema or elephantiasis of the leg living in filariasis-endemic areas of the Dominican Republic. Women in our study described a spectrum of consequences associated with their lymphedema but physical, functional, and psychological limitations were not always associated with severity of lymphedema. Data suggests that management frameworks need to be expanded to address women's explanatory models of illness, the cultural practices of seeking traditional healers for initial care, psychological distress, coping strategies unique to women, and the practice of self treating with antibiotics without medical supervision. Further research to better understand the depth and breadth of psychological states and coping strategies of women; the health seeking and self-management practices; and the strain on social support networks of women is needed in order to assist health program planners in establishing culturally tailored and gender-specific interventions for Dominican women.
[Show abstract][Hide abstract] ABSTRACT: In 2000, annual mass administration of diethlycarbamazine and albendazole began in Leogane Commune, Haiti, to interrupt transmission of lymphatic filariasis (LF). After 5 years of treatment, microfilaremia, antigenemia, and mosquito infection rates were significantly reduced, but LF transmission was not interrupted. These finding have implications for other LF elimination programs.
[Show abstract][Hide abstract] ABSTRACT: Lymphatic filariasis, a mosquito-borne parasitic disease, can lead to lymphoedema and elephantiasis. This study describes the results of a baseline survey of a lymphoedema morbidity management programme in Togo. A convenience sample of 188 people with lymphoedema was asked about symptoms, treatment preferences and quality of life. Those with higher stage lymphoedema were more likely to have experienced an acute attack (odds ratio=1.9; P=0.002). Although only 28.2% of those surveyed reported currently using any lymphoedema treatment, 80.3% had used treatments in the past, primarily traditional products (68.1%) and scarification (38.8%). Medication was the preferred treatment for acute attacks, both currently (73.1%) and in the past (61.7%). Patients reported difficulties performing activities such as walking to the field (44%) and carrying a heavy load (63%) as a result of their lymphoedema. Patients felt avoided by their family (17%) and their community (36%). Using the Duke Anxiety-Depression scale, over 70% of patients were found to be at high risk of depression and this risk increased with lymphoedema stage (P=0.04). The survey results demonstrate the need for a morbidity management programme that will increase the use of morbidity management techniques and decrease the physical and emotional burden of this disease.
Transactions of the Royal Society of Tropical Medicine and Hygiene 05/2007; 101(4):391-7. · 1.82 Impact Factor