WASH and NTDs: Outcomes and lessons learned from the implementation of a formative research study in NTD skin co-endemic communities in Benin.

Neglected Tropical Diseases (NTDs) are a diverse group of bacterial, viral, parasitic and fungal diseases affecting people, most of whom live below the poverty threshold. Several control strategies are defined against these diseases, including chemotherapy and Water, Hygiene and Sanitation (WASH). This study assesses the effect of promoting hygiene and sanitation on soil-transmitted helminthiasis s and NTDs of the skin. It took place in the communes of Ze, Lalo, and Zangnanado, three municipalities located in the south of Benin. This is a formative research that took place in three phases. The first phase entailed a baseline informations and situational analysis of the state of hygiene and health, using soil-transmitted helminthiasis and wound hygiene practices as cases studies. In the second phase, interventions to promote improved hygiene and sanitation were implemented. The third phase was devoted to post-intervention evaluation. The situation analysis showed that the prevalence of soil-transmitted helminthiasis was 6.43 and 7.10% in the municipalities of Ze and Lalo, respectively. In the communes of Zangnanado, the most common wound management practices identified were: putting sand or ashes in the wounds to keep flies away, the use of medicinal plants and the application of powder from antibiotic capsules for wound dressing. The post-intervention evaluation showed a decrease in the prevalence of soil-transmitted helminthiasis from 6.43 to 1.19% in the municipality of Lalo and from 7.10 to 1.75% in the municipality of Ze. In the commune of Zangnanado, a significant shift in wound management practices was noted, which led to the healing of several chronic wounds. This research supports the evidence that WASH-based interventions are very important to tackle neglected tropical diseases NTDs in addition to specific diseases based interventions.

A combined field study of Buruli ulcer disease in southeast Benin proposing preventive strategies based on epidemiological, geographic, behavioural and environmental analyses.

Buruli ulcer is a neglected tropical disease caused by M. ulcerans, an environmental mycobacterium. This cutaneous infectious disease affects populations with poor access to sanitation, safe water and healthcare living in rural areas of West and Central Africa. Stagnant open bodies of surface water and slow-running streams are the only risk factor identified in Africa, and there is no human-to-human transmission. Appropriate and effective prevention strategies are required for populations living in endemic areas. Based on a multidisciplinary approach in an area in which Buruli ulcer is endemic in South Benin, we investigated the link between all human-environment interactions relating to unprotected water and behaviors associated with Buruli ulcer risk likely to affect incidence rates. We characterised the sources of water as well as water bodies and streams used by communities, by conducting a prospective case-control study directly coupled with geographic field observations, spatial analysis, and the detection of M. ulcerans in the environment. A full list of the free surface waters used for domestic activities was generated for a set of 34 villages, and several types of human behaviour associated with a higher risk of transmission were identified: (i) prolonged walking in water to reach cultivated fields, (ii) collecting water, (iii) and swimming. Combining the results of the different analyses identified the risk factor most strongly associated with Buruli ulcer was the frequency of contact with unprotected and natural water, particularly in regularly flooded or irrigated lowlands. We confirm that the use of clean water from drilled wells confers protection against Buruli ulcer. These specific and refined results provide a broader scope for the design of an appropriate preventive strategy including certain practices or infrastructures observed during our field investigations. This strategy could be improved by the addition of knowledge about irrigation practices and agricultural work in low-lying areas.

Molecular and epidemiological characterization of recurrent Mycobacterium ulcerans infections in Benin.

BACKGROUND: Buruli ulcer is a neglected tropical disease caused by Mycobacterium ulcerans, an environmental mycobacterium. Although transmission of M. ulcerans remains poorly understood, the main identified risk factor for acquiring Buruli ulcer is living in proximity of potentially contaminated water sources. Knowledge about the clinical features of Buruli ulcer and its physiopathology is increasing, but little is known about recurrence due to reinfection. METHODOLOGY/PRINCIPAL FINDINGS: We describe two patients with Buruli ulcer recurrence due to reinfection with M. ulcerans, as demonstrated by comparisons of DNA from the strains isolated at the time of the first diagnosis and at recurrence. Based on the spatial distribution of M. ulcerans genotypes in this region and a detailed study of the behavior of these two patients with respect to sources of water as well as water bodies and streams, we formulated hypotheses concerning the sites at which they may have been contaminated. CONCLUSIONS/SIGNIFICANCE: Second episodes of Buruli ulcer may occur through reinfection, relapse or a paradoxical reaction. We formally demonstrated that the recurrence in these two patients was due to reinfection. Based on the sites at which the patients reported engaging in activities relating to water, we were able to identify possible sites of contamination. Our findings indicate that the non-random distribution of M. ulcerans genotypes in this region may provide useful information about activities at risk.

Effect of well drilling on Buruli ulcer incidence in Benin: a case-control, quantitative survey.

BACKGROUND: Buruli ulcer is the third most common mycobacterial disease worldwide. The public health burden of this neglected tropical disease is large, particularly in poor areas of west and central Africa. The development of appropriate preventive strategies is hampered by an incomplete understanding of the epidemiology and transmission of the disease. We investigated the effect of the drilling of wells on Buruli ulcer incidence. METHODS: In this case-control, quantitative survey, we obtained field data for Buruli ulcer incidence over a 10-year period from a specialised centre that collected data for the Ouémé and Plateau departments in Benin, and data for well drilling from the Ministry of Energy, Water and Mines in Benin. The coordinates of the wells drilled were obtained during site visits. A case-control study was then done to investigate the role of well water use in protecting against Buruli ulcer. FINDINGS: We found a strong inverse correlation between the incidence of Buruli ulcer and the number of new wells drilled in the Bonou municipality (r2=0·8818). A case-control study (106 cases and 212 controls) showed that regular use of the water from the wells for washing, bathing, drinking, or cooking was protective against Buruli ulcer (adjusted odds ratio 0·1, 95% CI 0·04-0·44; p=0·0012). INTERPRETATION: This study opens up new possibilities for developing an effective yet affordable policy to fight the disease on a substantial geographical scale. Our study shows that providing access to protected water is an efficient and feasable way to reduce the incidence of Buruli ulcer. FUNDING: Fondation Francaise Raoul Follereau, French National Institute of Health and Medical Research, and Région Pays de Loire.

Laboratory and field evaluation of the impact of washings on the effectiveness of LifeNet®, Olyset® and PermaNet® 2.0 in two areas, where there is a high level of resistance of Anopheles gambiae to pyrethroids, Benin, West Africa.

BACKGROUND: An investigation carried out in Benin has shown that, in some areas close to rivers where density of mosquitoes is high, long-lasting, insecticidal bed nets (LLINs) are permanently used. In such areas, LLINs are washed every month. Based on this situation, the 20-wash minimum efficacy advised by the manufacturers would be inadequate. The main goal of this study was to evaluate the effectiveness of LifeNet®, Olyset® and Permanet® 2.0 washed several times against Anopheles gambiae sensu stricto (s.s.) populations, which have developed high resistance to pyrethroids. METHODS: Efficacy of LifeNet®, Olyset® and PermaNet® 2.0 washed 30 and 40 times was expressed in terms of blood-feeding inhibition rate, deterrence, induced exophily and mortality rates. This WHOPES phase II evaluation, conducted in experimental huts in Akron (southern Benin) and in Malanville (northern Benin), was accompanied by WHOPES Phase I evaluation. RESULTS: Over 40 successive washes, LifeNet® induced a mortality rate over 80% in phase I. However, beyond 10 washes, Permanet® 2.0 and Olyset induced dramatically reduced mortality rates, respectively 12.5 and 2.5%. With regard to Phase II results, unwashed LifeNet®, LifeNet® and Olyset® washed 30 and 40 times induced a similar exophily rate per study site (at least 58% in Malanville and at least 71% in Akron). Regarding blood feeding inhibition, LifeNet® and Olyset® washed 30 and 40 times significantly reduced wild An. gambiae s.s. blood feeding showing a similar personal protection as unwashed LifeNet®. LifeNet® washed 30 and 40 times induced mortality rates significantly higher than those induced by Olyset® and Permanet® 2.0 (P < 0,05). CONCLUSION: LifeNet®, followed by Olyset®, have shown good efficacy against host-seeking resistant An. gambiae s.s. population in experimental huts in Benin. Lifenet® have shown to be an effective and promising vector control tool to prevent malaria in areas where repeated washings is a common practice in the community.