African Program for Onchocerciasis Control 1995-2010: Impact of Annual Ivermectin Mass Treatment on Off-Target Infectious Diseases

PLoS Negl Trop Dis. 2015 Sep 24;9(9):e0004051. doi: 10.1371/journal.pntd.0004051. eCollection 2015.

Abstract

Since its initiation in 1995, the African Program for Onchocerciasis Control (APOC) has had a substantial impact on the prevalence and burden of onchocerciasis through annual ivermectin mass treatment. Ivermectin is a broad-spectrum anti-parasitic agent that also has an impact on other co-endemic parasitic infections. In this study, we roughly assessed the additional impact of APOC activities on the burden of the most important off-target infections: soil-transmitted helminthiases (STH; ascariasis, trichuriasis, hookworm, and strongyloidiasis), lymphatic filariasis (LF), and scabies. Based on a literature review, we formulated assumptions about the impact of ivermectin treatment on the disease burden of these off-target infections. Using data on the number of ivermectin treatments in APOC regions and the latest estimates of the burden of disease, we then calculated the impact of APOC activities on off-target infections in terms of disability-adjusted life years (DALYs) averted. We conservatively estimated that between 1995 and 2010, annual ivermectin mass treatment has cumulatively averted about 500 thousand DALYs from co-endemic STH infections, LF, and scabies. This impact comprised approximately an additional 5.5% relative to the total burden averted from onchocerciasis (8.9 million DALYs) and indicates that the overall cost-effectiveness of APOC is even higher than previously reported.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Africa / epidemiology
  • Antiparasitic Agents / administration & dosage*
  • Disease Transmission, Infectious / prevention & control*
  • Helminthiasis / epidemiology*
  • Humans
  • Intestinal Diseases, Parasitic / epidemiology*
  • Ivermectin / administration & dosage*
  • Onchocerciasis / complications*
  • Onchocerciasis / drug therapy*
  • Onchocerciasis / epidemiology
  • Prevalence
  • Scabies / epidemiology*

Substances

  • Antiparasitic Agents
  • Ivermectin

Supplementary concepts

  • Intestinal helminthiasis

Grants and funding

This study was funded by the World Health Organization/African Programme for Onchocerciasis Control (APOC/CEV/322/07). MN, HGMZ, LB, and UVA are or have been employees of the African Programme for Onchocerciasis Control (APOC), World Health Organization, and were involved in data collection and writing of the manuscript. These authors state that their employment has not caused any conflict of interest in any of the following: study design, data collection, data analysis, interpretation, or decision to publish.