Abidjan/Brazzaville – Côte d'Ivoire has successfully eliminated human African trypanosomiasis, also known as “sleeping sickness” as a public health problem, becoming the second African country after Togo to be validated by the World Health Organization (WHO).

“I dedicate this milestone to decades of hard work and the individual contribution of every single health worker who braved some of the toughest challenges in reaching populations, often in remote rural areas,” said Dr Aka Aouele, Minister of Health and Public Hygiene of Cote d'Ivoire. “Our challenge now is to maintain the required level of surveillance and with the help of everyone to achieve interruption of transmission by 2030.”

Côte d'Ivoire reported hundreds of cases per year in the 1990s. Cases have progressively declined over the last two decades and in the past few years, the country reported fewer than 10 cases per year. At this low level, it qualifies to have eliminated the disease as a public health problem.

The achievement is attributed to robust control and surveillance measures, active (and passive) screening of people at risk and targeted vector control which helped to strongly decrease the number of cases in areas of transmission. Hospitals and health centres checked patients using specific diagnostic tests and laboratory mobile units screened people in villages.

Treatment of infected people meant that the vector, the tsetse fly, could no longer transmit the disease to others. This had to be maintained over years to progressively eliminate the disease.

“Cote d’Ivoire’s achievement marks an important step that brings Africa closer to eliminating sleeping sickness,” said Dr Matshidiso Moeti, WHO Regional Director for Africa. “Sustained control measures over the past two decades have brought a significant decline in cases – a positive sign that many countries will soon be crossing this landmark.”

"The result which Côte d'Ivoire has achieved after several decades of fighting the human African Trypanosomiasis demonstrates the excellent leadership of the Ministry of Health and Public Hygiene through the directorate of the HAT [human African Trypanosomiasis ] elimination programme. It is also an expression of the commitment and determination of the regional and departmental health directorates, health workers, communities' adherence to control measures as well as the power of partnerships,” said Dr Jean Marie Vianny Yameogo, WHO Representative in Côte d'Ivoire.

Two other countries – Benin and Equatorial Guinea – have submitted their dossiers to WHO, requesting validation of elimination as a public health problem.

Under WHO’s leadership, national control programmes, bilateral cooperation agencies and nongovernmental organizations have substantially reduced cases of the disease to unprecedented low numbers of less than one thousand globally before 2020.

Sleeping sickness is a potentially fatal disease spread by the bite of an infected tsetse fly, a species native to the African continent. More than 60 million people in 36 countries who live mainly in rural parts of East, Central and West Africa are at risk of contracting the disease.

Validation of elimination as a public health problem

The validation per country is done by WHO. A complete dossier must be submitted to present detailed information on the past and present of the disease incidence throughout the territory. The country must show evidence of effective, ongoing surveillance to prove that the capacity of detecting the disease is strong. The figures must be below the specific thresholds required by WHO, which means below one case per 10 000 inhabitants in all districts, during a five-year period.

WHO and partners are targeting the interruption of transmission of the Trypanosoma brucei gambiense form of the disease in all endemic countries by 2030.

The main approaches to controlling sleeping sickness include reducing the reservoirs of infection and the presence of the tsetse fly.

Screening of people at-risk helps identify patients at an early stage. Diagnosis should be made as early as possible to avoid complicated and risky treatment procedures of the advanced stage.

The disease

Human African trypanosomiasis is a vector-borne parasitic disease caused by infection with protozoan parasites belonging to the genus Trypanosoma. The causative parasite is transmitted to humans through the bite of the tsetse fly (Glossina genus) that has acquired infection from humans or animals harbouring the human pathogenic parasites.

There are two forms: one due to the gambiense trypanosome which is found in 24 countries in West and Central Africa and accounts for more than 98% of cases. The other, due to Trypanosoma brucei rhodesiense, is found in 13 countries in Eastern and Southern Africa and represents the rest of the cases.

When bitten by the tsetse fly, a red sore may erupt within a few weeks. The person can experience fever, swollen lymph nodes, aching muscles and joints, headaches and irritability.

People who get infected feel lethargic and sleepy by day then awake and exhausted at night. Neuropsychiatric and sensory disorders follow, then a coma before death within months or sometimes even years later.