The World Health Organization (WHO) congratulates Niger for having met the criteria for onchocerciasis elimination, making it the fifth country globally and the first country in Africa to be acknowledged by WHO for interrupting transmission of the parasite Onchocerca volvulus.
Eliminating a disease is a significant achievement that requires tireless dedication," stated Dr Tedros Adhanom Ghebreyesus, WHO Director-General. "I congratulate Niger for its commitment to liberating its population from this blinding, stigmatizing illness that causes so much human suffering among the poorest. This success is yet another testament to the remarkable strides we have made against neglected tropical diseases and offers hope to other nations still battling onchocerciasis, demonstrating that elimination is possible."
Onchocerciasis, commonly known as river blindness, is a parasitic disease and is the second leading infectious cause of blindness worldwide, after trachoma. It is transmitted to humans through the bites of infective black flies, primarily found in riverine areas. The disease primarily affects rural populations in sub-Saharan Africa and Yemen, with smaller endemic areas found in parts of Latin America.
Effective country-led efforts and partnerships
Between 1976 and 1989, under the umbrella of the WHO Onchocerciasis Control Programme in West Africa (OCP), Niger undertook vector control measures by spraying insecticides that significantly decreased levels of onchocerciasis transmission. Following the donation of ivermectin by Merck, Sharpe & Dohme (MSD), areas still affected by lymphatic filariasis (LF) underwent mass drug administration (MDA) with ivermectin and albendazole from 2008 to 2019, followed by surveillance. Since ivermectin is effective against both diseases, and areas targeted for LF MDA were also endemic for onchocerciasis, this intervention also contributed to interrupting the transmission of the Onchocerca volvulus parasite.
Niger started preliminary assessments on interruption of onchocerciasis transmission in 2014 after stopping LF MDA in most areas. This was followed by entomological and epidemiological surveys which revealed that the combination of medicine and vector control had successfully eliminated transmission of onchocerciasis, as evidenced by the reduction in prevalence from approximately 60% to 0.02%.
In addition to the vector control interventions and the medicines donated by MSD, a key factor contributing to Niger's success is the partnership between the Nigerien government, WHO and nongovernmental organizations, which has helped mobilize resources and technical support. Continuous monitoring of the disease's prevalence and its impact has enabled timely adjustments in strategies and ensured the effectiveness of interventions.
"Onchocerciasis has long caused immense human suffering. It has also impeded the economic development of affected communities, driving people away from rivers, which are often lifelines for livelihoods," says Dr Matshidiso Moeti, WHO Regional Director for Africa. "Niger's success ends this burden for its people. It also positions Niger as a model for the elimination of neglected tropical diseases in Africa. The country previously demonstrated its leadership in public health, by eliminating Guinea-worm disease in 2013. Today, it takes another historic step forward."
Global progress
Globally, 54 countries have eliminated at least one neglected tropical disease.
Niger joins four other countries that have been verified by WHO for eliminating onchocerciasis, all in the Region of the Americas: Colombia (2013), Ecuador (2014), Guatemala (2016) and Mexico (2015).
In the WHO African Region, 21 countries have eliminated at least one neglected tropical disease. Onchocerciasis is the second neglected tropical disease eliminated in Niger: the country was certified free of dracunculiasis (Guinea-worm disease) transmission in 2013.
