Cooking copepods: The survival of cyclopoid copepods (Crustacea: Copepoda) in simulated provisioned water containers and implications for the Guinea Worm Eradication Program in Chad, Africa

Abstract

Introduction: The global Guinea Worm Eradication Program has reduced numbers of human infections of Guinea worm disease (dracunculiasis) to 49 cases in four countries. However, infections of domestic animals (dogs and cats) have recently been recognized and are increasing. Typically, Guinea worm (Dracunculus medinensis) transmission occurs via the ingestion of copepods from water. Despite several interventions, including tethering of dogs while worms emerge, the number of infected dogs continue to increase. One hypothesis is that dogs could be infected through the ingestion of copepods in provisioned water.

Objectives: The purpose of this study was to determine whether copepods can survive in water containers under typical Chadian temperatures.

Methods: Four container types (plastic, glass, gourd, and metal) were seeded with copepods and exposed to simulated Chadian temperatures.

Results: All copepods in the metal containers died within 4 h. Conversely, after 8 h live copepods were still present in plastic, glass, and gourd containers.

Conclusions: If provisioned water is provided to potential hosts of D. medinensis, metal containers create the most inhospitable environment for copepods. Plastic containers have little effect on copepod mortality. The use of metal containers for water provisions could be a useful tool assisting with the interruption of D. medinensis transmission among dogs.

Keywords: Copepod survival; Domestic dogs; Dracunculus medinensis; Guinea worm; Transmission; Water.