|Some Neglected Diseases Could be Eliminated in the Americas, PAHO Paper Says|
Washington, DC, February 18, 2011 (PAHO) - This fact sheet describes the activities carried out by the PAHO
Communicable Disease Project for its neglected disease team to prevent,
control and eliminate neglected ('forgotten') diseases primarily
affecting the most vulnerable, impoverished, and marginalized
populations. Parasitic diseases are a large part in the program's work,
but the scope is now broader and follows a more integrated and
multi-disease approach to create multisectoral action and cost-effective
interventions to combat these poverty-related diseases.
Areas of Work
Neglected Diseases: What are they? What is the situation in the Americas? Neglected diseases are a group of parasitic and other infectious diseases that are generally characterized by historically low investment by the pharmaceutical sector and that mainly affect the poorest segments of society. Among these neglected diseases are lymphatic filariasis, onchocerciasis, intestinal helminthiasis, schistosomiasis, and leishmaniasis:
Soil-transmitted helminths (STHs, or geohelminths): PAHO/WHO estimates that 20–30% of all Latin Americans are infected with intestinal helminths (worms), while the figures in slums often reach 50% and even go up to 95% in some Amerindian tribes.
Schistosomiasis (Schistoma mansoni) still affects at least eight countries in the Region, with Brazil carrying the largest burden with at least 2.5 million people estimated to be infected and 6 million at risk.
Lymphatic filariasis (filarial elephantitis) affects over half a million people in the Region with up to 6–8 million at risk (conservatively), principally in Haiti but also in Guyana, Dominican Republic, and northeastern Brazil.
Onchocerciasis (river blindness) puts about half a million people at risk in the Region. Its most problematic focus encompasses an extensive region of remote communities on the border of southern Venezuela with northern Brazil.
Leishmaniasis: Both types (cutaneous and visceral) are a growing problem in rural and peri-urban areas in many countries of the Region, with about 35,000 total cases reported in Brazil alone in 2003. However, under-reporting or lack of reporting is common in the rural and peri-urban marginal areas of the Region where these diseases are usually found.
Prevention, Control and/or Elimination Programs: Global
elimination or control programs exist for geohelminths,
schistosomiasis, onchocerciasis, and lymphatic filariasis; but global
resources are scarce. There are WHO and PAHO resolutions for the
elimination of onchocerciasis and lymphatic filariasis as public-health
problems, and an initiative is underway to address these in an
integrated manner as “neglected diseases”, along with geohelminths,
schistosomiasis, and other tropical diseases. To interrupt transmission
of onchocerciasis, treatment coverage of no less than 85% must be
maintained over a period of 12 to 14 years, while treatment coverage
above 80% over a period of five years is critical to interrupting the
transmission of lymphatic filariasis in endemic countries.
There has been steady progress in achieving these goals. However, program sustainability depends on political will; and significant advocacy is required.
Geohelminthiasis and schistosomiasis are serious public health problems primarily affecting the school-age population and women of childbearing age, as well as adolescents and young working adults. To address this disease burden, at least 75% of school-age children living in areas at risk for geohelminths and schistosomiasis will require access to regular chemotherapy by 2010, as identified in World Health Assembly (WHA) Resolution 54.19 (2001); where the two diseases overlap, combined treatment is recommended by WHO guidelines, along with improved water and sanitation and health education.
Surveillance and outbreak investigation, as well as prevention and control programs for leishmaniasis, need strengthening in some countries.
A multi-disease and integrated approach to management of these neglected diseases is desirable due to the synergies, logistical efficiencies, and potential cost-savings to be realized in both prevention activities and case management (patient care). Cost-effectiveness data need to be developed for both single- and multi-disease interventions to assist in evidence-based decision-making.
Formulating Strategies and Providing Technical Cooperation: This program is formulating integrated, multidisease-, interprogrammatic-, and intersectoral-based strategies for disease prevention, control and/or elimination, as well as incorporating cost-effectiveness analysis—all based in evidence and with a clear vision towards fulfillment of the Millennium Development Goals MDGs and the development of a neglected diseases agenda. PAHO actively promotes the formulation of national plans, policies and strategies towards prevention, control and/or elimination of neglected communicable diseases; provides technical cooperation to countries with an emphasis on capacity-building of national institutions; and promotes cooperation among and between countries in the Region.
Neglected diseases are listed by category as follows:
Notes: Brazil does not consider any
infectious disease in its territory as neglected but does recognize the
existence of diseases of poverty in its territory.
WHO includes the majority of the diseases on this page under the heading of neglected tropical diseases. Plague and hantavirus, however, are not strictly tropical diseases.