The varied beneficial effects of ivermectin (Mectizan) treatment, as observed within onchocerciasis foci in south–eastern Nigeria

Abstract

In the treatment of humans, ivermectin (Mectizan((R))), a semi-synthetic macrocyclic lactone, is now primarily used as a rapid microfilaricide. The drug has several other benefits, however, and these have recently been investigated in five states in south-eastern Nigeria, where there have been mass treatments with ivermectin, for the control of Onchocerca volvulus, for more than 10 years. Between the January and December of 2005, 3125 adult onchocerciasis patients (each aged >/=20 years and known to have at least one clinical sign of onchocerciasis) were enlisted, clinically examined and interviewed. Relevant data were collected in the interviews, using a structured, pre-tested questionnaire, and in personal and focus-group discussions. Overall, 612 (19.6%) of the subjects reported that they had had nodules that had disappeared following repeated doses of ivermectin, although only 83.8% of the 612 attributed their nodule clearance to ivermectin (the other 16.2% being unsure of the cause). A larger percentage of the subjects (24.6%) reported that they had expelled intestinal helminths following the last round of ivermectin treatment (i.e. been dewormed). Other side-benefits reported in the study were improved vision (11.7% of subjects), reversal of secondary amenorrhea (4.5%), increased appetite (22.3%), reduction in arthritic or other musculo-skeletal pain (7.9%), reductions in the severity of body itching (18.5%) and skin rash (17.3%), darkening of leopard skin (6.6%), improved libido in men (6.6%), and clearance of head lice (4.5%). If, via health education, the local communities could be made more aware of the side-benefits of ivermectin treatment, the sustainability of the on-going programme of community-directed treatment with ivermectin (CDTI) in south-eastern Nigeria would probably be improved.

The African Programme for Onchocerciasis Control: impact on onchocercal skin disease

“…Ivermectin is known to be effective against both scabies (Strong & Johnstone 2007), and head lice (Anosike et al. 2007; Pilger et al.…”

Impact of scabies in resource-poor communities

“…A reduction of the transmission of soil-transmitted helminth infections and scabies in affected communities has also been perceived as an additional benefit within the ivermectin-based Onchocerciasis Control Program [65][66][67]. Similarly in Nigeria, communities reported additional benefits of ivermectin mass treatment against onchocerciasis [68]: about one-fourth reported to have expelled intestinal helminths after treatment with ivermectin, 19% improved body itching, and 17% reduced skin rash possibly because of scabies; others reported clearance of head lice infestations [68]. We have observed during mass treatments in Brazil aiming at the reduction of ectoparasites that community members were referring to ivermectin as 'God's drug', as they had noticed that the skin did not itch any more, worms were expelled from the intestine, and head lice were falling off the head (J. Heukelbach, personal communication).…”

Self-Diagnosis of Head Lice Infestation in Rural Nigeria as a Reliable Rapid Assessment Tool for Pediculosis

“…A study by Anosike et al (2007) in five states of Nigeria assessed clearance of pediculosis as an additional benefit of an ivermectin onchocerciasis control program [11]. They did not examine people for head lice, but relied on selfdiagnosis.…”

“…Rapid assessment methods using self-diagnosis have been used for a limited number of parasitic diseases with distinctive signs, such as haematuria in urinary schistosomiasis [12,13]. Diseases that can be reliably self-diagnosed enable health personnel and community health workers in affected populations to collect epidemiological data about the prevalence of a disease in a cost-effective manner [11]. In addition, self-diagnosis of pediculosis in this region could be a basis for treatment of head lice infestation without confirmation by health care personnel.…”