Unprecedented progress against neglected tropical diseases reported

people walking jungle

GENEVA/WASHINGTON, April 19, 2017-The World Health Organization reported remarkable achievements in tackling neglected tropical diseases (NTDs) since 2007, with an estimated 1 billion people in 2015 alone receiving treatment.

"WHO has observed record-breaking progress towards bringing ancient scourges like sleeping sickness and elephantiasis to their knees," said WHO Director-General, Dr Margaret Chan. "Over the past 10 years, millions of people have been rescued from disability and poverty, thanks to one of the most effective global partnerships in modern public health."

The new report, Integrating Neglected Tropical Diseases in Global Health and Development, demonstrates how strong political support, generous donations of medicines, and  improvements in living conditions, have led to sustained expansion of disease control programs in countries where these diseases are most prevalent. Since 2007, when a group of global partners met to agree to tackle NTDs, a variety of local and international partners have worked alongside ministries of health in endemic countries to deliver quality-assured medicines, and provide people with care and long-term management.  

"The countries in our Region are close to eliminating some of the neglected tropical diseases with the help of partners and the finest technical cooperation led by PAHO and WHO, but we need more help to finish the job and rid the Americas of these tropical diseases that can be eliminated," said Dr. Marcos Espinal, who heads Communicable Diseases and Health Analysis at the Pan American Health Organization (PAHO).

Speaking on behalf of PAHO Director Carissa F. Etienne at the panel on NTD Financing, Espinal discussed country progress and commitment, partnerships and the need to nurture for success, citing examples from the Region. "People living in poverty shouldn't have to suffer from a debilitating disease that we can prevent for pennies, he added."

Since 2007, when a group of global partners met to agree to tackle NTDs together, a variety of local and international partners have worked alongside ministries of health in endemic countries to deliver quality-assured medicines, and provide people with care and long-term management.  

In 2012, partners endorsed a WHO NTD Roadmap, committing additional support and resources to eliminating 10 of the most common NTDs.

Key achievements include:

  • 1 billion people treated for at least one neglected tropical disease in 2015 alone;
  • 556 million people received preventive treatment for lymphatic filariasis (elephantiasis);
  • More than 114 million people received treatment for onchocerciasis (river blindness:   62% of those requiring it;
  • Only 25 human cases of Guinea-worm disease were reported in 2016, putting eradication within reach;
  • Cases of human African trypanosomiasis (sleeping sickness) have been reduced from 37,000 new cases in 1999 to well under 3,000 cases in 2015;
  • Trachoma - the world's leading infectious cause of blindness - has been eliminated as a public health problem in Oman, Morocco and Mexico. More than 185 000 trachoma patients had surgery for trichiasis worldwide and more than 56 million people received antibiotics in 2015 alone;
  • Visceral leishmaniasis: in 2015 the target for elimination was achieved in 82% of sub-districts in India, 97% of sub-districts in Bangladesh, and in 100% of districts in Nepal.
  • Only 12 reported human deaths were attributable to rabies in the Region of the Americas in 2015, bringing the region close to its target of eliminating rabies in humans by 2015. 

 However, the report highlights the need to further scale up action in other areas.

"Further gains in the fight against neglected tropical diseases will depend on wider progress towards the Sustainable Development Goals," said Dr Dirk Engels, Director of the Department of Control of Neglected Tropical Diseases.

Meeting global targets for water and sanitation will be key. WHO estimates that 2.4 billion people still lack basic sanitation facilities such as toilets and latrines, while more than 660 million continue to drink water from "unimproved" sources, such as surface water.

Meanwhile, global concern about the recent outbreaks of Zika virus disease, and its associated complications, has re-energized efforts to improve vector control. In May this year, the World Health Assembly will review proposals for a new Global vector control response. There are also brighter prospects to prioritize cross-sectoral collaboration to promote veterinary public health.

Situation in the Americas

Last year, health leaders of the member countries of the Pan American Health Organization (PAHO) agreed on a plan of action to eliminate eight neglected infectious diseases and to significantly reduce the burden of five others over the next six years. The plan also calls for actions to reduce the risk of reintroduction of these diseases in the post-elimination phase.

The diseases targeted for interruption of transmission or elimination by 2022 are: trachoma, Chagas disease, human rabies transmitted by dogs, leprosy, human taeniasis and cysticercosis tapeworm infections, lymphatic filariasis, onchocerciasis (river blindness), and schistosomiasis. The following are targeted for prevention, control, and a reduction in the burden of disease: cystic echinococcosis (hydatidosis), fascioliasis, human plague, leishmaniasis (cutaneous and visceral), and soil-transmitted helminth infections (intestinal worms).

Neglected infectious diseases affect primarily populations living in extreme poverty and cause suffering, permanent disability, and death. In Latin America and the Caribbean, an estimated 46 million children live in areas at high risk of infection or reinfection with soil-transmitted helminths, while nearly 11 million people are at risk of blinding trachoma, and 70.2 million are at risk of Chagas disease.

More than 33,000 new cases of leprosy and over 51,000 cases of cutaneous leishmaniasis are reported in the Americas each year. In addition, 70 million people in the region are at risk of Chagas disease, 25 million suffer from schistosomiasis, and 12.6 million suffer from lymphatic filariasis.

To control and eventually eliminate these diseases in the Americas, PAHO/WHO promotes and supports strategies including the mass distribution of antiparasitics and other medicines, integrated vector control, and health education in communities.

Progress in the Americas 2009-2015

  • Colombia, Ecuador, Mexico, and Guatemala were the first countries in the world to receive WHO certification of elimination of human onchocerciasis.
  • The number of people needing treatment for onchocerciasis in the region declined from more than 336,000 in 2009 to just over 25,000 in 2015.
  • Seventeen Central and South American countries have eliminated vector-borne transmission of Chagas disease in all or part of their national territory.
  • Almost all the countries in the Americas have eliminated leprosy as a national public health problem.
  • Fourteen countries are considered free of local malaria transmission.
  • Three countries have eliminated lymphatic filariasis and have not reported any local transmission, while three more are close to elimination.
  • In 2013, nearly 20 million children were treated for soil-transmitted helminth infections in the Region.
  • Six countries and territories in the Caribbean may have eliminated the transmission of schistosomiasis, but there are still some areas with transmission in limited foci.

Neglected Tropical Diseases

  • Dengue: mosquito-borne viral disease causing flu-like illness. Occasionally develops into a lethal complication called severe dengue.
  • Rabies:viral disease transmitted to humans through the bites of infected dogs. Invariably fatal once symptoms develop.
  • Trachoma:infection transmitted through direct contact with eye or nasal discharge. Causes irreversible corneal opacities and blindness.
  • Buruli ulcer:debilitating skin infection causing severe destruction of the skin, bone and soft tissue.
  • Yaws: chronic bacterial infection affecting mainly the skin and bone.
  • Leprosy:caused by infection mainly of the skin, peripheral nerves, mucosa of the upper respiratory tract and eyes.
  • Chagas disease:: infection transmitted through contact with vector insects, ingestion of contaminated food, infected blood transfusion, congenital transmission, organ transplantation or laboratory accidents.
  • Human African trypanosomiasis(sleeping sickness) parasitic infection spread by bites of tsetse flies. Almost 100% fatal without prompt diagnosis and treatment.
  • Leishmaniases: transmitted through the bites of infected female sandflies. In its most severe (visceral) form, it attacks the internal organs. The most prevalent (cutaneous) form causes face ulcers, disfiguring scars and disability.
  • Taeniasis and neurocysticercosis: infection by adult tapeworms in human intestines; cysticercosis occurs when humans ingest tapeworm eggs that develop as larvae in tissues.
  • Dracunculiasis (guinea-worm disease): nematode infection transmitted by drinking-water contaminated with parasite-infected water fleas.
  • Echinococcosis: infection caused by larval stages of tapeworms forming pathogenic cysts. Transmitted to humans through ingestion of eggs, shed in faeces of dogs and wild animals.
  • Foodborne trematodiases: infection acquired by consuming fish, vegetables and crustaceans contaminated with larval parasites.
  • Lymphatic filariasis:Infection transmitted by mosquitoes causing abnormal enlargement of limbs and genitals from adult worms inhabiting and reproducing in the lymphatic system.
  • Mycetoma: debilitating, disabling bacterial/fungal skin infection thought to be caused by the inoculation of fungi or bacteria into the subcutaneous tissue.
  • Onchocerciasis (river blindness): parasitic eye and skin disease, transmitted by the bite of infected blackflies. Causes severe itching and eye lesions, leading to visual impairment and permanent blindness.
  • Schistosomiasis: larval worm infection. Transmission occurs when larval forms released by freshwater snails penetrate human skin during contact with infested water.
  • Soil-transmitted helminthiases: group of intestinal helminth infections transmitted through soil contaminated by human faeces.