By: Charles Ebikeme

In late June 1962, a joint expert committee met in Geneva, Switzerland. The topic was Human African trypanosomiasis (HAT), otherwise known as sleeping sickness. The published report hailed “spectacular successes” on the disease and “…control measures directed at the parasite by means of chemotherapy and chemoprophylaxis have reduced incidence of the disease to an extremely low level.” Old world colonial territories like Rhodesia and Nyasaland reported limited numbers of new cases per year. Double-digit figures were not exceptional for many parts of the continent. The “traditional trypanocides” used to treat the disease (tartaremetic, Atoxyl, Orsanine, tryparsamide and suramin) had given way to aromatic diamidines and melaminyl radical compounds. Tsetse flies that spread the disease were intensely monitored. Surveying tsetse populations was labor and man-power intensive. Fly-rounds by trained specialists to spot and catch flies, marking “apparent density” of fly populations per 10,000 yards. Tedious. Results were a rough estimate at best, changing with activity and availability of the flies, not to mention some species of tsetse require large cattle baits to be counted. Tsetse breeding areas were targeted using DDT with blanket applications that proved economical and effective. Together with selective clearing of vegetation and game destruction brought the burden down to minimal levels.

Without a doubt, trypanosomiasis, thanks to international efforts, was at its lowest level since records began. For the next few decades it would seem that sleeping sickness would no longer pose a threat to human health and development on the African continent. The rage of the disease was manageable, and in time would fade into the background.

This year, in a case of history repeating, a collection of papers published in PLoS Neglected Tropical Diseases hails that African trypanosomiasis is at its lowest level for the first time in 50 years. The number of new cases diagnosed with sleeping sickness in 2009 has dropped below 10,000. The caveat to this triumph harks back to the complacency of earlier decades; “If the decline in the reported HAT cases is taken at face value, it could signal African governments to abandon their local control efforts and for funding agencies to modify their disease research priorities. Should this happen, it is most certain that epidemics will likely flare up in the near future as has happened in the past.”

The history of HAT has always been one of a lack of choice; with major pharmaceutical companies needing convincing to develop or even continue making the life saving drugs. In decades that have passed, much has changed and yet very little has. Pentamidine and suramin remain as the drugs of choice. Old drug regimes haven’t really given way to better therapies. We have new a combination therapy in the form of NECT (nifurtimox eflornithine combination therapy) – postulated as early as 1985, but little in the way of choice. With only two drugs to treat the chronic form of the disease. One of which, is the “deadly drug” we all know of – Melarsoprol. On the horizon, a nitroheterocycle compound, fexinidazole, whose parasite killing activity was first shown nearly 30 years ago, has just entered clinical trials.

The collection published in PLoS Neglected Tropical Diseases hails successes in diagnostics, detection, tsetse control as well as epidemiological predictions – prompting the obligatory cautionary tale. All this success in the light of the fact that our toolbox to controlling the disease hasn’t vastly improved in decades. “It would be timely now to take a very hard look at the global research agenda within the context of a forgotten hinterland which, up until the 1960s, demonstrated that this disease could be controlled effectively by unsophisticated means—a history all too conveniently forgotten by, or perhaps unknown to, most of the current generation of researchers.”

Wars, displaced populations, fragmented efforts and a lack of cohesion all in the face of continued research led to the inevitable rise of epidemics. An unstable African continent, wars, genocide, Côte d’Ivoire, Democratic Republic of Congo, and refugees threaten to fragment concerted efforts. Then and now. Bill Gates wanting to rid the world of Polio once and for all. Sleeping sickness sliding down the global research agenda. In a simple word – neglect.

But perhaps a different spin on this is needed. In an effort to make sure history doesn’t repeat itself perhaps the time for elimination is now. As early as in 2005 the call for elimination was put forward by the International Scientific Council for Trypanosomiasis Research and Control. Recommending that WHO should “launch an elimination programme for sleeping sickness, adopt strategies towards this goal and advocate all partners who have permanently provided support to maintain their efforts and assistance.”

Are we there yet? What would it take to eliminate Human African trypanosomiasis? A final push with the tools we have now? Or something novel in terms of drugs and therapy? The miracle drug. The magic bullet. What will it take?

Charles Ebikeme has worked for many years as a research scientist on African Sleeping Sickness. Possessing a MSc from the London School of Hygiene & Tropical Medicine, and a PhD in Parasitology from the University of Glasgow, Charles currently blogs and writes for the All Results Journals – a new publication system focusing on negative results – covering topics on the hidden side of the scientific publication process.