In many parts of the Global South, notably in sub-Saharan Africa, schistosomiasis remains a major issue for the rural populace. Schistosomiasis, also known as bilharzia or snail fever, is an infectious disease that is commonly caused by flatworms borne by snails. Snail fever has a long list of negative consequences for the communities it is present in. For one, it disproportionately affects children who end up suffering from stunted growth and learning deficits. Looking from a wider perspective, snail fever has been evidenced to kill 200,000 people in the world every year.

Now that we know how big of an issue snail fever is in certain parts of the world, we are now left to wonder how does this disease spread so easily? After all, snails are not as elusive as other infection-spreading animals, like mosquitoes, are. The answer to this is aquatic vegetation. It is a common practice for villagers to visit freshwater sources, such as ponds, for regular day-to-day activities, from washing clothes to bathing. Unfortunately, these freshwater sources are often covered by aquatic vegetation that serves as the habitat for the snails that contain the disease-spreading flatworms. These snails release the larvae of the flatworms into the water, thus making the freshwater sources a hotbed for the parasites.

Under normal circumstances, deworming drugs are provided as a treatment. While they do a good job as a treatment, deworming drugs fail to prevent the spread of the disease in the first place. Fortunately, previous trials conducted as a preamble to this research project have shown good promise of an alternative mechanism, which hits at the root cause. This mechanism is termed aquatic vegetation removal.

Aquatic vegetation removal has appeared to work well as a long-term process and has been very successful at reducing snail fever infection rates in locations (in rural Northern Senegal) where it has been trialed. However, aquatic vegetation keeps on reappearing meaning that aquatic vegetation removal is a process that requires a lot of resources, in the form of labor and time. Despite the success of this mechanism, there needs to be other benefits to it in order to justify the costs.

Luckily, through this research project, we have been able to identify just that. First and foremost, clearing away the aquatic vegetation does help with access to freshwater sources, which are so vital for the daily activities of the villagers. However, it does not end there. For those wondering, there are indeed more long-term positive consequences. Trials carried out as part of the project showed that compost derived from the aquatic vegetation had noticeably positive results in improving the profitability of pepper and onion harvests, even under conservative assumptions about the cost of labor used to clear vegetation and make and apply compost. Not only that, but it also acted as a cheaper form of feed than the current feed provided to sheep in these regions. This means that during the time of the year when there is an inadequate amount of forage for livestock, the removed aquatic vegetation has the added purpose of acting as a diet supplement for the livestock too.

Before taking any concrete decision, it is important for us to first observe the reality on the ground and analyze the data we collect. For our purposes, 20 Senegalese villages were selected. To ensure that they were fit for purpose, the villages were chosen such that they had a fresh water source with known snail fever transmission, within 10 km, and also had at least one water access point with vegetation clearly present. From these villages, 40 household heads were randomly chosen and then allocated to two treatment groups in a random manner too. Both groups were provided with information on the fact that the aquatic vegetation removed from the water bodies can be used, on a private basis, as compost to boost agricultural yields and also as feed for livestock. However, only the second group was also informed on how the process of aquatic vegetation removal has public health benefits, by reducing the transmission rates for snail fever (for fairness purposes, the other group was also informed of these benefits after the data collection was over). To ensure all the necessary information went through, posters displaying the relevant information visually were also presented, along with verbal explanations.

Within each of the treatment groups themselves, there were two further sub-groups with one sub-group partaking in an auction for 5 kg of compost and the other sub-group engaging in an auction for 5 kg of animal feed. This means there were four separate auctions taking place in each village. These were all conducted simultaneously and in separate locations away from any line of sight. This was to prevent any biases resulting from observing the decisions and behaviors of those participating in the other auctions. Another important note is that all the auctions were carried out in the second-price methodology, as it has been established by prior economics research that this is a more accurate way of figuring out how much demand for the item being auctioned there is. In this auction mechanism structure, the highest bidder still wins the item auctioned but pays the price raised by the second-highest bidder. If the highest bidder does not have an adequate amount of funds to make the purchase, the rights to the item go to the second-highest bidder who pays the bid price raised by the third-highest bidder, and so on the process goes until we reach someone with the ability to pay the price mentioned.

By noting down the information gathered from these auctions, we are able to establish the true willingness to pay of the villagers, for the compost and animal feed. In this way, we are able to create accurate demand curves which will help us quantify the benefits of aquatic vegetation removal, and see if, in relation to the costs, the process of aquatic vegetation removal gets justified.