From blindness and agonizing pain to critically damaging internal organs and disfiguring limbs, the ways in which neglected tropical diseases (NTDs) can wreak havoc on the human body are seemingly endless.

But one of the most detrimental ways that NTDs attack the body may actually be invisible.

The relationship between NTDs and nutrition is, quite literally, a competition. Parasites and bacterial diseases live in the same space, taking over the host — in this case, a human body — and compete for their nutrients from food.

As the body works to fight off disease — by increasing its metabolic rate, while decreasing its appetite and immune responses — it also ends up depleting nutrients and energy faster. The body’s ability to take in nutrients is reduced, as internal tissue is damaged. Nearly all roads lead to undernutrition, which ends up making a person even more susceptible to disease. It's a lose-lose situation.

Take Action: Download the App to Take Action on Neglected Tropical Diseases and More Global Citizen Issues

Marginalized communities suffer from chronic undernutrition already — 1 in 5 children in developing countries is underweight. NTDs only serve to exacerbate risks of malnourishment. Some NTDs, like intestinal worms and schistosomiasis (a parasitic worm), infect more than 1 billion people worldwide, according to the World Health Organization (WHO). Both of these NTDs cause anemia and malnutrition, which can put expectant mothers and children at risk.

Still, the competition between NTDs and nutrition isn’t clearly established. It’s more comparable to a chicken-or-egg scenario.

Intestinal infections, such as worms, are shown to be associated with undernutrition and stunted growth. Parasites like worms feed on their host’s diet, which leads the body to become undernourished. But perhaps a person who is undernourished already (and therefore more vulnerable to infections) is more susceptible to the sickness. Which comes first? Did the undernourishment cause the infection, or did the infection cause the undernourishment?

Researchers are still unclear because subjecting participants to either undernutrition or infection for the extent of a study is highly unethical. For now, prospective studies can only show that there is an existing negative relationship between NTDs and nutrition — it just can’t be said which causes the other.

NTDs cause many vicious cycles. The disfigurements that come from some NTDs can lead to social stigma, which often leads to unemployment. This pushes vulnerable individuals and their caretakers, usually family, toward food insecurity, perpetuating a cycle of poverty and poor nutritional status.

But it doesn’t even take infection to rob people of nutritious food. The threat alone of NTDs is enough to drive vast populations into food insecurity. NTDs can infect people to the point of being unable to work, including farmers, whose livelihood depend on crops that also feed their families — but the mere risk of infection on farmland itself can force people to abandon their farms.

After onchocerciasis, an NTD also known as river blindness that can cause bumps under the skin, itching, and blindess, had spread across 11 countries in West Africa in the 1970s, the WHO launched the Onchocerciasis Control Program (OCP) to prevent the growing transmission of larvae carrying the river blindness parasite. The program was established to protect 30 million people in Benin, Burkina Faso, Côte d'Ivoire, Ghana, Guinea Bissau, Guinea, Mali, Niger, Senegal, Sierra Leone, and Togo.

After more than a decade, they were able to restore 25 million hectares of arable farming land to make it safe for cultivation — enough land to feed millions of people each year.

In the majority of cases, however, NTDs hold the upper hand on humans when left untreated, taking over a person’s body and robbing their ability to work, or taking over their land and livelihood.

NTDs almost always have a negative effect on a person’s nutrition, but it’s also possible the opposite is true, and good nutrition can stave off NTDs. While the best way to prevent and treat NTDs is through mass drug administration, nutritional rehabilitation can help restore a person in recovery.

Research has shown that children's appetites increase after treating intestinal worms or schistosomiasis. Drugs treat the disease and reduce risk of reinfection, but good nutrition is required for recovery and long-term vitality. This could mean nutritional supplements, but also clean water and sanitation.

Providing vitamins and minerals to restore nutrient deficiencies, especially in children, might be the answer to a healthy future — helping to achieve the United Nations Sustainable Development Goal 3 on good health and well-being for all.

The 2018 Global Citizen Festival in New York will be presented for the very first time by Citi. MSNBC and Comcast NBCUniversal will air a live simulcast of the Festival on MSNBC and The Festival will also be livestreamed on YouTube and Twitter, presented by Johnson & Johnson.

Proud partners of the 2018 Global Citizen Festival include Global Citizen’s global health partner and major partner Johnson & Johnson, and major partners P&G, CHIME FOR CHANGE Founded by Gucci, Verizon, House of Mandela, iHeartMedia, and NYC Parks. Associate partners include Microsoft, Great Big Story, and One Championship.


Defeat Poverty

What Do Neglected Tropical Diseases Have to Do With Nutrition?

By Diana Duong