River blindness (onchocerciasis) is a parasitic disease prevalent in 31 Sub-saharan Africa areas. If not controlled, it is a major impediment to socio-economic development because it leads to severe disabilities, including blindness.
Following decades of large-scale efforts to reduce parasite transmission and health impact, the World Health Organisation (WHO) and African countries are now aiming to eliminate the disease, where feasible. LTS will support these efforts by providing WHO with a transdermal delivery patch for diagnosis of infection.
Onchocerciasis is one of 17 neglected tropical diseases that collectively affect around one billion people worldwide, primarily those living in impoverished conditions in urban slums or remote rural areas.
Onchocerciasis is endemic over much of Sub-Saharan Africa, in Yemen and several small areas in six Central and South American countries. Large-scale disease control efforts were initiated in the 1970s with the formation of the WHO onchocerciasis control programme (OCP) in West Africa, where the population had deserted fertile areas along the rivers to escape the black flies that breed there and transmit the parasite causing blindness in as much as 10% of the population.
Onchocerciasis control was expanded to Central and East Africa when the WHO African programme for onchocerciasis control (APOC) was formed in 1995. Its objective was to work with Ministries of Health and non-governmental organisations to set up sustainable annual distribution of a single dose of ivermectin to nearly the total population living in areas where the disease is highly prevalent. By 2012, the programme included more than 180,000 communities in 31 endemic African countries to reduce the enormous burden of onchocerciasis.
Via the annual treatment of all eligible people living in areas at risk of the disease with ivermectin, a drug that kills the juvenile form of onchocerca volvulus, APOC has achieved impressive results. The prevalence of onchocerciasis has decreased so significantly in several areas that it is close to elimination.
However, further steps are urgently needed to accelerate the elimination of onchocerciasis. The main task is to detect regional pockets where the disease is still endemic . This requires a state-of-the-art diagnostic system suitable for large-scale use.
Building on the principles of the diethylcarbamazine (DEC) patch test, developed in the 1980s and 1990s, LTS applied its expertise to develop an innovative transdermal delivery technology-based DEC-containing patch, which is applied within around ten seconds, is aseptic and non-invasive, and is expected to be well-accepted throughout the population.
DEC kills the juvenile forms of the parasite residing in the skin underneath the patch which leads to a diagnostic skin reaction. Availability of this patch will allow APOC and the onchocerciasis endemic countries to monitor progress towards elimination of the infection and to implement appropriate measures to accelerate elimination where and when necessary.
LTS developed the diagnostic patch at no charge to the WHO. WHO and LTS have now signed an agreement for the long-term supply of DEC patches by LTS to WHO. APOC will supply the patches to the National Programmes in Africa.