Diseases like HIV/AIDS, cholera and malaria disproportionately affect the world’s poorest populations.

But amongst those well-known diseases of poverty are others that are much less well-known and yet, just as threatening — they are called neglected tropical disease (NTDs).

NTDs are a cluster of parasitic and bacterial diseases that cause illnesses like chagas disease, Guinea worm disease, human African trypanosomiasis, visceral leishmaniasis, leprosy, lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths, trachoma, and more.

Take Action: No One Should Suffer From Diseases We Know How to Treat or Prevent

These diseases blind, disfigure, and debilitate people in urban slums and in the poorest regions of the world, according to the World Health Organization (WHO).

While you may have heard of a few of these, it’s likely you know very little about their actual effects or why they are so often overlooked.

“Essentially the neglect is on account of the lack of attention to these diseases with the respect to adequate therapies,” Dr. John Amuasi, the executive director of African Research Network for Neglected Tropical Diseases (ARNNTD) told Global Citizen.

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There are solutions readily available for some NTDs, but they are not widely deployed, according to Amuasi.

“The diseases affect the poorest of the poor and so there’s very little incentive for them to be addressed,” he said.

He explained that some pharmaceutical companies that might normally conduct research and development for diseases like these don’t bother as there is no market for the drugs.

Having said that, there are also pharmaceutical companies like GlaxoSmithKline (GSK) and Johnson & Johnson that donate treatment around the world — which is why global commitments to the elimination of NTDs could go a long way in ensuring treatment reaches the people who need it most.

Read More: These 7 Countries Eliminated a Neglected Tropical Disease in 2017 — and More Will Follow in 2018

Amuasi also pointed out that because these diseases affect the poorest populations, the people do not have much of a voice, meaning that governments are not worried about their votes or delivering on campaign promises related to NTDs.

There are 149 countries and territories worldwide that are affected by at least one NTD — 100% of low-income countries are affected by many. NTDs are also found in countries like the US and Canada.

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They prevail in tropical and subtropical conditions and affect more than 1 billion people, according to WHO. They are commonly found in remote or developing areas, infecting some of the world’s most vulnerable populations.

“The poorest of the poor are those who are exposed to living conditions which are unsanitary,” Amuasi said. “[They] live in close proximity to the vectors or to disease-causing organisms.”

One example Amuasi gave was soil-transmitted helminths.

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Soil-transmitted helminths (STH) are intestinal worms. People can become infected with hookworks, one kind of STH, when their feet come into contact with soil contaminated with eggs or pathogens. As you can imagine, in poor populations, people are often walking around barefoot.

“If poverty is addressed as the root of the matter, it would have a significantly positive effect on NTDs,” he said.

Last April, WHO reported that an estimated 1 billion people received treatment for NTDs in 2015 alone.

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The report outlined that political support, donations of medicines, and improvements in living conditions helped expand disease control programs in countries most affected by NTDs.

Still, the report acknowledged that more needs to be done to address NTDs.

It suggested that meeting global targets for water and sanitation will be key, among other advancements in the accomplishment of the United Nations Sustainable Development Goal.

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Dr. Stan Houston is a professor of medicine and of public health at the University of Alberta and a specialist in infectious diseases and tropical medicine.

He echoes Amuasi in saying that treatments need to be made more readily available and that there are diseases in desperate need of new and more effective methods of treatment.

He makes the case for this using African sleeping sickness as an example.

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“It’s the only disease left on the planet where, under some circumstances, we still chase with an arsenic-based drug,” he said.

Arsenic is a well-known poison, but there are certain situations where the arsenic-based medication is the only option.

Even in Canada, he added, some important medications that are on the WHO essential drugs list are extremely difficult to obtain.

“There is a very cumbersome, opaque and inconsistent process that you have to go through to get those medications,” he said.

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Preventive chemotherapy for neglected tropical diseases is available and there are many efforts being made to make it more accessible through mass drug administration, Amuasi said.

But these medications are often only available during those mass drug cycles, meaning if someone is diagnosed with an NTD through their regular health system, they are often still unable to access treatment.

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Many organizations are working towards securing funding for research and development on NTDs, including Amuasi’s network, ARNNTD, which is trying to secure funding to do indigenous African research to address these diseases.

But an important step forward would see governments committing funding for the delivery of the already existing drugs.

“The presence of NTDs is a very important measure of the degree of poverty within any setting,” Amuasi said, “We cannot say we are addressing poverty without addressing NTDs, and you cannot really address NTDs without addressing poverty.”

Global Citizen campaigns on the United Nations Sustainable Development Goals, including issues related to global health, knowing that ensuring good health is key to pulling people out of extreme poverty. You can take action here.

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Defeat Poverty

Neglected Tropical Diseases: Everything You Need to Know

By Jackie Marchildon