Test & Treat
2011-2018
Rapid identification of high levels of Loa loa microfilaremia: a « test and treat » strategy for mass drug administration
Rationale
Lymphatic filariasis (LF) and onchocerciasis (Oncho) are Neglected Tropical Diseases (NTDs) caused by different species of filarial nematode parasites and are responsible for significant morbidity and loss of productivity in the tropics and subtropics, including much of sub-Saharan Africa. Since the early 1990s, it has been recognized that ivermectin, the drug used by current programs to control LF and Oncho, causes serious adverse events (SAEs) including death in individuals harboring high levels of a third filarial parasite, Loa loa, in the blood. This has hampered ivermectin distribution in areas in Central and West Africa, where loiasis is coendemic with LF and/or Oncho. This situation is of great concern because the final objective of the LF and Oncho control program is eradication, which cannot be accomplished if regions are excluded from treatment.
Objectives
To develop and validate a field-friendly, point-of-care test to identify those individuals with high densities of Loa loa microfilariae (mf) in the blood (i.e., at high risk of SAEs) so that they can be excluded from mass drug administration (MDA) with ivermectin allowing safe treatment of the rest of the population
To demonstrate the feasibility of this approach in a field-setting
To use the data from the field study to inform mathematical models to address the effects of excluding a subset of individuals from MDA on the success of elimination programs
To provide data to the WHO for consideration of the addition of TNT to the guidelines for treatment in areas coendemic for loiasis and onchocerciasis