Pyrethroid insecticides pose greater risk than organophosphate insecticides to biocontrol agents for human schistosomiasis.

Use of agrochemicals, including insecticides, is vital to food production and predicted to increase 2-5 fold by 2050. Previous studies have shown a positive association between agriculture and the human infectious disease schistosomiasis, which is problematic as this parasitic disease infects approximately 250 million people worldwide. Certain insecticides might runoff fields and be highly toxic to invertebrates, such as prawns in the genus Macrobrachium, that are biocontrol agents for snails that transmit the parasites causing schistosomiasis.

Exposure, hazard, and vulnerability all contribute to Schistosoma haematobium re-infection in northern Senegal.

Background: Infectious disease risk is driven by three interrelated components: exposure, hazard, and vulnerability. For schistosomiasis, exposure occurs through contact with water, which is often tied to daily activities. Water contact, however, does not imply risk unless the environmental hazard of snails and parasites is also present in the water.

Land use impacts on parasitic infection: a cross-sectional epidemiological study on the role of irrigated agriculture in schistosome infection in a dammed landscape.

Background: Water resources development promotes agricultural expansion and food security. But are these benefits offset by increased infectious disease risk? Dam construction on the Senegal River in 1986 was followed by agricultural expansion and increased transmission of human schistosomes. Yet the mechanisms linking these two processes at the individual and household levels remain unclear.

Visualization of schistosomiasis snail habitats using light unmanned aerial vehicles.

Schistosomiasis, or "snail fever", is a parasitic disease affecting over 200 million people worldwide. People become infected when exposed to water containing particular species of freshwater snails. Habitats for such snails can be mapped using lightweight, inexpensive and field-deployable consumer-grade Unmanned Aerial Vehicles (UAVs), also known as drones.

Unavoidable Risks: Local Perspectives on Water Contact Behavior and Implications for Schistosomiasis Control in an Agricultural Region of Northern Senegal.

Human schistosomiasis is a snail-borne parasitic disease affecting more than 200 million people worldwide. Direct contact with snail-infested freshwater is the primary route of exposure. Water management infrastructure, including dams and irrigation schemes, expands snail habitat, increasing the risk across the landscape.

Emerging human infectious diseases and the links to global food production.

Infectious diseases are emerging globally at an unprecedented rate while global food demand is projected to increase sharply by 2100. Here, we synthesize the pathways by which projected agricultural expansion and intensification will influence human infectious diseases and how human infectious diseases might likewise affect food production and distribution. Feeding 11 billion people will require substantial increases in crop and animal production that will expand agricultural use of antibiotics, water, pesticides and fertilizer, and contact rates between humans and both wild and domestic animals, all with consequences for the emergence and spread of infectious agents.

Potential Biological Control of Schistosomiasis by Fishes in the Lower Senegal River Basin.

More than 200 million people in sub-Saharan Africa are infected with schistosome parasites. Transmission of schistosomiasis occurs when people come into contact with larval schistosomes emitted from freshwater snails in the aquatic environment. Thus, controlling snails through augmenting or restoring their natural enemies, such as native predators and competitors, could offer sustainable control for this human disease.

Role of environmental parameters on the density of intermediate host snails of human schistosoma during the year in the commune of Richard-Toll, Senegal.

The implementation and expansion of development projects (dams and irrigation schemes) in the Senegal River valley have led to a significant proliferation of snails. We conducted a one-year (2014) study project, monitoring their density in the commune of Richard Toll, to assess the role of environmental parameters on mollusc population dynamics. Four species involved in the transmission of human schistosomiasis were found: Bulinus globosus, B.

Agrochemicals increase risk of human schistosomiasis by supporting higher densities of intermediate hosts.

Schistosomiasis is a snail-borne parasitic disease that ranks among the most important water-based diseases of humans in developing countries. Increased prevalence and spread of human schistosomiasis to non-endemic areas has been consistently linked with water resource management related to agricultural expansion. However, the role of agrochemical pollution in human schistosome transmission remains unexplored, despite strong evidence of agrochemicals increasing snail-borne diseases of wildlife and a projected 2- to 5-fold increase in global agrochemical use by 2050.

Reduced transmission of human schistosomiasis after restoration of a native river prawn that preys on the snail intermediate host.

Eliminating human parasitic disease often requires interrupting complex transmission pathways. Even when drugs to treat people are available, disease control can be difficult if the parasite can persist in nonhuman hosts. Here, we show that restoration of a natural predator of a parasite's intermediate hosts may enhance drug-based schistosomiasis control.

The prawn Macrobrachium vollenhovenii in the Senegal River basin: towards sustainable restocking of all-male populations for biological control of schistosomiasis.

Early malacological literature suggests that the outbreak of schistosomiasis, a parasitic disease transmitted by aquatic snails, in the Senegal River basin occurred due to ecological changes resulting from the construction of the Diama dam. The common treatment, the drug praziquantel, does not protect from the high risk of re-infection due to human contact with infested water on a daily basis. The construction of the dam interfered with the life cycle of the prawn Macrobrachium vollenhovenii by blocking its access to breeding grounds in the estuary.

[Collection of mollusk intermediate hosts of Schistosoma at two sites in Lampsar (Senegal River valley): quantitative reproducibility].

We studied the number of mollusks collected according to a specific protocol: 2 samplers prospecting in opposite directions for 1 min 30 s at 10 collection points regularly distributed on the site, for a total of 2 times 15 minutes. Because of the good reproducibility of the results of these collections, this method can be used for quantitative studies. A sampling effect was noted.

[Using the capture-mark-recapture method for quantitative assessment of populations of molluscs in two sites in Lampsar (Valley of the Senegal River)].

The authors have made an estimate of the number of mollusc by the capture-mark-recapture method at two sites in the Valley of the Senegal River. This quantification is necessary to track the effect of the introduction in one of the sites of a native shrimp Machrobrachium vollenhovenii, predator of mollusc. The populations of two study sites were approximately 1,800 and 1,500 individuals with coefficients of variation of about 30%.

[Evaluation of the Kato-Katz technique for monitoring Schistosoma mansoni infestation in endemic areas].

The Kato-Katz technique has become the gold standard for all studies on intestinal schistosomiasis. Though repeatability and reproducibility can be disappointing and the sensitivity is low, it remains easy, inexpensive, and fast and as such, is perfectly suited for epidemiological surveys or to monitor the effectiveness of mass treatment. For optimal interpretation of the Kato-Katz results in a recent study of three endemic villages in the Senegal River basin, a study of the measurement uncertainties of this analysis was conducted according to Cofrac and ISO 15189 guidelines.