More than 400 million people are at risk for the neglected tropical diseases (NTDs) visceral leishmaniasis (kala azar), sleeping sickness, Chagas disease, and Buruli ulcer. The first three are among the deadliest of all the NTDs, and all four have been highlighted by the World Health Organization (WHO) as especially troublesome due to treatment and diagnostic tools that are old, ineffective, or worst, simply non-existent, and with patient populations stuck in remote or insecure areas with little or no access to health care. Even worse, research and development (R&D) of new medicines and diagnostics is woefully under funded. Unless there is a substantial increase in resources available for national control programs for active diagnosis and treatment of patients, investment in prevention initiatives, as well as dedicated R&D for new tools, victims of these will remain neglected.
About 500,000 new cases of kala azar are seen each year, and it is increasing as an opportunistic infection for people living with HIV/AIDS. Liposomal amphotericin B (AmBisome) is a highly effective treatment but its cost and logistics have restricted its wider use. For example, in Bihar, India, MSF pays $18 per vial of this drug, with a treatment course ranging in costs from $200-$300 per patient, making it too costly for wide implementation by health ministries and to be purchased by most individuals. The only other option for most patients is 28 days of extremely painful intramuscular injections of sodium stibogluconate (SSG), a drug developed in the 1930s.
The fatal parasitic disease sleeping sickness (human African trypanosomiasis) is found in sub-Saharan Africa, and patients are especially vulnerable in regions of armed conflict where the disease is endemic and health services are at a minimum. MSF currently manages programs in two such countries, the Democratic Republic of Congo (DRC) and Central African Republic (CAR). MSF recently successfully tested a new combination treatment, nifurtimox-eflornithine combination therapy (NECT), with the Drugs for Neglected Diseases initiative, that is easier to administer and shorter in duration than older treatment regimens, and is considerably safer than the existing standard treatment, melarsoprol, an arsenic-based treatment that kills up to 10 percent of patients. NECT has now been adopted by some countries, but efforts must continue for wider implementation.
Chagas disease (American trypanosomiasis) is endemic in parts of Latin America, with up to 15 million cases worldwide, including 300,000 in the United States. An estimated 30 percent of Chagas patients will develop heart and digestive complications that can lead to death. Few diagnosis and treatment programs exist for Chagas disease, and MSF currently runs three programs in Bolivia and Colombia. Medical response to Chagas requires active testing, treatment with the currently available drugs benznidazole and nifurtimox, and R&D for new diagnostics and drugs.
While not deadly, Buruli ulcer, in the same family as leprosy and tuberculosis, can cause deformity and disability and sometimes life-threatening secondary infections. MSF currently treats the disease in Cameroon, and though simple and effective treatments like antibiotics, proper wound care, physiotherapy, and minor surgery exist, they are insufficiently available.
In human terms, the cost of ongoing neglect of these diseases is tremendous. R&D spending for these four diseases was a low as $81.4 million, according to a 2008 analysis. New financing and incentive mechanisms are urgently needed to ensure R&D is driven by health needs and not just profitable markets.
The recently announced US Global Health Initiative (GHI) focuses on some neglected diseases, but does not currently include these four diseases, threatening further neglect of diseases that impact the world’s most impoverished and marginalized people. It is imperative people suffering from these diseases have immediate access to available treatments alongside efforts to develop more effective and accessible treatments with fewer side effects and better diagnostic tests for patients in the future.