Applied field research for comprehensive helminth infection control.

Area of Science:

• Tropical medicine
• Infectious diseases
• Parasitology

Background:

• The University of Tübingen's Institute for Tropical Medicine established a Research Centre and Onchocerciasis Reference Laboratory (ORL) in Togo 30 years ago.
• Activities focused on Onchocerca volvulus and other neglected tropical diseases, in collaboration with Togolese health institutions.

Purpose of the Study:

• To assess the long-term impact of ivermectin treatment on onchocerciasis.
• To investigate the prevalence and impact of co-infections with intestinal and intravascular parasites.
• To understand the cellular immune responses to parasite co-infections.

Main Methods:

• Longitudinal monitoring of onchocerciasis prevalence and manifestations over 24 years.
• Implementation of repeated annual ivermectin treatments.
• Application of albendazole and praziquantel for intestinal parasite and Schistosoma spp. infections.
• Analysis of cellular immune responses in co-infected individuals.

Main Results:

• 24 years of ivermectin treatment significantly reduced onchocerciasis prevalence and its ocular/dermal manifestations.
• High prevalence of concurrent intestinal and intravascular protozoan/helminth parasite infections identified in rural populations, especially school children.
• Repeated deworming treatments reduced infection intensities by over 80%.
• Parasite co-infections induce pro-inflammatory immune responses.

Conclusions:

• Ivermectin is effective in controlling onchocerciasis but does not address concurrent parasitic infections.
• Eliminating co-infections and establishing balanced immunity requires sustained, multi-faceted interventions.
• Further research is needed on the complex immune dynamics of co-infections in endemic regions.