The development of water management infrastructures, such as dams and canals, are
important components of society’s response to feed a growing human population and to
fight climate change. Yet, these changes in land use can also increase the transmission risk
for waterborne diseases. Transmission risk associated with artificial reservoirs has been
extensively documented for schistosomiasis, a parasitic disease of poverty that infects more
than 240 million people worldwide. Over 90% of these cases are in sub-Saharan Africa, a
region that is being steadily reshaped by climate change. Controlling the parasite’s obligate
intermediate host snail is key to reducing transmission of this disease. Using commercial
aquaculture to farm marketable species which predate upon these snails in vulnerable
regions can have multiple positive effects, including the improved socioeconomic and
nutritional health of surrounding communities. Here the authors assessed the viability of
using the aquaculture of snail predators to simultaneously control schistosomiasis infection
rates while alleviating economic and/or nutritional poverty in endemic regions of sub-Saharan
Africa. A PRISMA-based 6-step systematic methodology was used to explore the primary
literature using the case study of Côte d’Ivoire and two native species of snail predator to
make evidence-based conclusions on the viability of this method for controlling schistosomiasis.
This detailed thematic examination of the literature concluded that using specific approaches
and species, aquaculture could be effective in reducing economic poverty and chronic
malnourishment along with high levels of schistosomiasis infection. More current
species-specific aquaculture data and consumer survey data are, however, needed to
determine the economic and logistical effectiveness of farming native snail predators
in-country. These and other opportunities for future research are highlighted.
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Interventions can shift the thermal optimum for parasitic disease transmission
Temperature constrains the transmission of many pathogens. Interventions that target temperature-sensitive life stages, such as vector control measures that kill intermediate hosts, could shift the thermal optimum of transmission, thereby altering seasonal disease dynamics and rendering interventions less effective at certain times of the year and with global climate change. To test these hypotheses, we integrated an epidemiological model of schistosomiasis with empirically determined temperature-dependent traits of the human parasite
- PAR ID:
- 10216680
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 118
- Issue:
- 11
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- Article No. e2017537118
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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