Neglected tropical diseases (NTDs) contribute to a “poverty trap,” which not only affects the health and well-being of millions of people, but also prevents them from working — thus impacting agricultural production around the world.
An NTD outbreak can be devastating and exacerbate already dire conditions for malnourished or food-insecure populations.
Farmers working close to livestock and fisherfolk casting their nets in waters potentially infected by parasites are two groups particularly vulnerable to NTD infections.
Schistosomiasis, for example, is a parasite that is carried through both infested bodies of freshwater and infected snails, and often affects fishing communities.
In a study of 150 fishermen who lived in the Lake Manzala region in Egypt, more than a quarter had schistosomiasis infection in their stool, according to a 2014 study published in Asian Pacific Journal of Tropical Disease.
Some NTDs can have debilitating effects that render people completely unable to work. Many studies have shown that risk of lymphatic filariasis — an infection that obstructs the lymphatic system and causes swollen limbs — is higher for occupations such as farming, plantation work, and fishing. When a farmer or a fisher is unable to work, this not only limits their livelihood, but directly affects their family and their community.
Even if NTDs don’t infect people, the risk of infection itself can be enough to threaten food security by forcing populations to flee affected areas.
In the 1970s, onchocerciasis, an eye and skin disease caused by worms that is transmitted through blackfly bites, affected roughly 2.5 million people in West Africa. It was estimated that 60% of people who lived in some parts of river valleys were afflicted with the disease, according to a report by the United Nations.
Under threat of infection, villagers were forced to abandon kilometres-long stretches of arable farming land, parts of which has been described as “some of West Africa's richest river lands.”
Food production suffered as villagers were forced to abandon fertile valleys for poor-quality soil that was already crowded and overfarmed, causing severe environmental degradation.
Food security is also directly affected when animals become infected with NTDs.
Ruminants, such as cattle, sheep, and goats, struggle to gain any weight when they’ve become infected with helminth, according to researchers in a 2014 study. And cows infected with nematodes produce up to 15% less milk, according to a 2011 study from Argentine researchers.
From impaired worker productivity and reduced harvests to widespread abandonment of fertile farmland, NTDs are one of the most potent drivers of food insecurity for the bottom billion of the world. Eliminating NTDs would mean eliminating one of strongest reinforcements of poverty traps — and increasing food security worldwide.