Loa loa-does it deserve to be neglected?

Abstract

More than 10 million people in western and central Africa are estimated to be infected with Loa loa filarial nematodes. Like most other infectious diseases, L loa filariasis (loiasis) covers a wide range of symptoms. Severe complications have been reported; however, most observations are anecdotal, typically in travellers. The widespread use of filaricidal drugs within eradication programmes of Onchocerca volvulus and Wuchereria bancrofti led to the observation that concomitant L loa infection increases the risk of severe treatment-associated, life-threatening complications. Initiatives were therefore launched to map the risk of loiasis. Insight about the epidemiology of L loa has advanced notably; however, its effect on the individual as well as on the community level has not been well studied. In the absence of appropriate studies, L loa is commonly judged a harmless nematode, and loiasis as a separate entity does not belong to the list of neglected tropical diseases to be controlled or eradicated in worldwide campaigns. We advocate reorientation of research efforts towards a patient-centric view of loiasis and, as a first step, to establish the disease burden in disability-adjusted life-years of this chronic infection, and to answer the question of whether loiasis should be included in future control programmes.