Exposure to Schistosoma mansoni infection in a rural area in Brazil. Part III: household aggregation of water-contact behaviour

Abstract Background Annual mass drug administration with praziquantel has reduced schistosomiasis transmission in some highly endemic areas, but areas with persistent high endemicity have been identified across sub-Saharan Africa, including Uganda. In these areas many children are rapidly reinfected post treatment, while some children remain uninfected or have low-intensity infections. The aim of this mixed-methods study was to better understand variation in water contact locations, behaviours and infection risk in school-aged children within an area with persistent high endemicity to inform additional control efforts. Methods Data were collected in Bugoto, Mayuge District, Uganda. Two risk groups were identified from a longitudinal cohort, and eight children with no/low-intensity infections and eight children with reinfections were recruited. Individual structured day-long observations with a focus on water contact were conducted over two periods in 2018. In all identified water contact sites, four snail surveys were conducted quarterly over 1 year. All observed Biomphalaria snails were collected, counted and monitored in the laboratory for Schistosoma mansoni cercarial shedding for 3 weeks. Results Children came into contact with water for a range of purposes, either directly at the water sources or by coming into contact with water collected previously. Although some water contact practices were similar between the risk groups, only children with reinfection were observed fetching water for commercial purposes and swimming in water sources; this latter group of children also came into contact with water at a larger variety and number of sites compared to children with no/low-intensity infection. Households with children with no/low-intensity infections collected rainwater more often. Water contact was observed at 10 sites throughout the study, and a total of 9457 Biomphalaria snails were collected from these sites over four sampling periods. Four lake sites had a significantly higher Biomphalaria choanomphala abundance, and reinfected children came into contact with water at these sites more often than children with no/low-intensity infections. While only six snails shed cercariae, four were from sites only contacted by reinfected children. Conclusions Children with reinfection have more high-risk water contact behaviours and accessed water sites with higher B. choanomphala abundance, demonstrating that specific water contact behaviours interact with environmental features to explain variation in risk within areas with persistent high endemicity. Targeted behaviour change, vector control and safe water supplies could reduce reinfection in school-aged children in these settings. Graphical Abstract

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The distribution of Biomphalaria spp. in different habitats in relation to physical, biological, water contact and cognitive factors in a rural area in Minas Gerais, Brazil

Memórias do Instituto Oswaldo Cruz ◽

10.1590/s0074-02762001000900008 ◽

2001 ◽

Vol 96 (suppl) ◽

pp. 57-66 ◽

Cited By ~ 21

Author(s):

Helmut Kloos ◽

Cecilia de Souza ◽

Andrea Gazzinelli ◽

Britaldo Silveira Soares Filho ◽

Plinio da Costa Temba ◽

...

Keyword(s):

Rural Area ◽

Minas Gerais ◽

Cognitive Factors ◽

Water Contact ◽

Biological Water

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Predicting frequency distribution and influence of sociodemographic and behavioral risk factors of Schistosoma mansoni infection and analysis of co-infection with intestinal parasites

Geospatial health ◽

10.4081/gh.2015.303 ◽

2015 ◽

Vol 10 (1) ◽

Cited By ~ 5

Author(s):

Carla V.V. Rollemberg ◽

Marília M.B.L. Silva ◽

Karla C. Rollemberg ◽

Fábio R. Amorim ◽

Nayanna M.N. Lessa ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Low Income ◽

Intestinal Parasites ◽

Kernel Estimation ◽

Kernel Estimator ◽

Integrated Approach ◽

Parasitic Infections ◽

Behavioral Risk ◽

Water Contact ◽

Untreated Water

Geospatial analysis was used to study the epidemiology of Schistosoma mansoni, intestinal parasites and co-infections in an area (Ilha das Flores) in Sergipe, Brazil. We collected individually georeferenced sociodemographic, behavioral and parasitological data from 500 subjects, analyzed them by conventional statistics, and produced risk maps by Kernel estimation. The prevalence rates found were: S. mansoni (24.0%), Trichuris trichiura (54.8%), Ascaris lumbricoides (49.2%), Hookworm (17.6%) and Entamoeba histolytica (7.0%). Only 59/500 (11.8%) individuals did not present any of these infections, whereas 279/500 (55.8%) were simultaneously infected by three or more parasites. We observed associations between S. mansoni infection and various variables such as male gender, being rice farmer or fisherman, low educational level, low income, water contact and drinking untreated water. The Kernel estimator indicated that high-risk areas coincide with the poorest regions of the villages as well as with the part of the villages without an adequate sewage system. We also noted associations between both A. lumbricoides and hookworm infections with low education and low income. A. lumbricoides infection and T. trichiura infection were both associated with drinking untreated water and residential open-air sewage. These findings call for an integrated approach to effectively control multiple parasitic infections.

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Exposure to Schistosoma mansoni infection in a rural area in Brazil. II: Household risk factors

Tropical Medicine & International Health ◽

10.1046/j.1365-3156.2001.00685.x ◽

2001 ◽

Vol 6 (2) ◽

pp. 136-145 ◽

Cited By ~ 52

Author(s):

Jeffrey Bethony ◽

Jeff T. Williams ◽

Helmut Kloos ◽

John Blangero ◽

Lucia Alves-Fraga ◽

...

Keyword(s):

Risk Factors ◽

Schistosoma Mansoni ◽

Rural Area

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The Impact of Artesunate-Amodiaquine on Schistosoma mansoni Infection among Children Infected by Plasmodium in Rural Area of Lemfu, Kongo Central, Democratic Republic of the Congo

BioMed Research International ◽

10.1155/2018/3487183 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Kennedy Makola Mbanzulu ◽

Josué Kikana Zanga ◽

Jean Pierre Kambala Mukendi ◽

Felly Mbaya Ntita ◽

Junior Rika Matangila ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Rural Area ◽

Reduction Rate ◽

Haemoglobin Concentration ◽

Sub Saharan Africa ◽

Parasitic Infections ◽

Prospective Longitudinal Study ◽

Infection Pattern ◽

Prospective Longitudinal ◽

The Impact

Background. Malaria and schistosomiasis remain life-threatening public health problems in sub-Saharan Africa. The infection pattern related to age indicates that preschool and school-age children are at the highest risk of malaria and schistosomiasis. Both parasitic infections, separately or combined, may have negative impacts on the haemoglobin concentration levels. The existing data revealed that artemisinin derivatives commonly used to cure malaria present also in antischistosomal activities. The current study investigated the impact of Artesunate-Amodiaquine (AS-AQ) on schistosomiasis when administered to treat malaria in rural area of Lemfu, DRC. Methodology. A prospective longitudinal study including 171 coinfected children screened for anaemia, Schistosoma mansoni, and Plasmodium falciparum infections. The egg reduction rate and haemoglobin concentration were assessed four weeks after the treatment with AS-AQ, of all coinfected children of this series. Results. One hundred and twenty-five (74.4%) out of 168 coinfected children treated and present during the assessment were found stool negative for S. mansoni eggs. Out of 43 (25.6%) children who remained positives, 37 (22%) showed a partial reduction of eggs amount, and no reduction was noted in 3.6% of coinfected. The mean of haemoglobin concentration and the prevalence of anaemia were, respectively, 10.74±1.5g/dl , 11.2±1.3g/dl, and 64.8%, 51.8%, respectively, before and after treatment, p<0.001. Conclusion. The AS-AQ commonly used against Plasmodium allowed curing S. mansoni in coinfected children and increasing the Hb level. For the future, the randomized and multicentric clinical trials are needed for a better understanding of the effectiveness of AS-AQ against Schistosoma spp. The trial registration number was 3487183.

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Distribution and Schistosoma mansoni infection of Biomphalaria glabrata in different habitats in a rural area in the Jequitinhonha Valley, Minas Gerais, Brazil: environmental and epidemiological aspects

Memórias do Instituto Oswaldo Cruz ◽

10.1590/s0074-02762004000700002 ◽

2004 ◽

Vol 99 (7) ◽

pp. 673-681 ◽

Cited By ~ 24

Author(s):

Helmut Kloos ◽

Liana Kanovaloff Janotti Passos ◽

Philip LoVerde ◽

Rodrigo Correa Oliveira ◽

Andréa Gazzinelli

Keyword(s):

Schistosoma Mansoni ◽

Rural Area ◽

Biomphalaria Glabrata ◽

Minas Gerais

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Biological implications of the phenotypic plasticity in the Schistosoma mansoni - Nectomys squamipes model

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652008000400008 ◽

2008 ◽

Vol 50 (4) ◽

pp. 229-232 ◽

Cited By ~ 6

Author(s):

Elaine Machado Martinez ◽

Michele Costa-Silva ◽

Renata Heisler Neves ◽

Regina Maria Figueiredo de Oliveira ◽

José Roberto Machado-Silva

Keyword(s):

Phenotypic Plasticity ◽

Schistosoma Mansoni ◽

Biological Behavior ◽

Egg Viability ◽

Patent Period ◽

Water Contact ◽

Schistosomiasis Mansoni ◽

Infectivity Rate ◽

Biological Modification

The water-rat Nectomys squamipes is mostly important non-human host in schistosomiasis mansoni transmission in Brazil, due to its susceptibility, high abundance and water-contact pattern. During experimental infection of N. squamipes with Schistosoma mansoni, adult worms show phenotypic plasticity. This finding led us to investigate whether biological behavior is also affected. This was assessed comparing the biological characteristics of four S. mansoni strains: BE (State of Belém do Pará), CE (State of Pernambuco), CMO (State of Rio Grande do Norte) and SJ (State of São Paulo) using laboratory-bred N. squamipes. The infection was monitored by determination of the pre-patent period, fecal egg output, egg viability, intestinal egg count and, infectivity rate. No biological modification was observed in these parameters. Overall results highlight that N. squamipes was susceptible to several S. mansoni strains, suggesting that it might contribute to the maintenance of schistosomiasis mansoni in Brazil.

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