Infection rate, distribution and relative abundance of cyclopoid copepods in dracunculasis endemic foci of Ebonyi State, Nigeria

Abstract

Between February 2001 and January 2002 studies on the infection rates, distribution and relative abundance of cyclopoid copepods were carried out on 15 sources of drinking water, which were sources commonly used in some selected guinea worm endemic villages in 3 L.G.As (Ebonyi, Ikwo, izzi) of Ebonyi State, Nigeria. In all, a total of 6,502 cyclops were collected of which 132 (2.03%) were infected with the larvae of Dracunculus medinensis. Five different species of Cyclops were encountered and identified. These include: Thermocyclops Oblongatusnigerianus, Mesocyclopseaquatorialis, Tropocyclopsconfinis and Mesocyclopsespericonis. However, only T. oblongatusnigerianus and M. aequatorialis harboured infected larvae of the worm. Infected cyclopoid copepods population was highest in March 2001 with density of 1017/liter while August, which is the peak of the raining season, had the lowest Cyclops density with none infected. A positive correction (r = +0.1) was established between vector infectivity and prevalence of the disease in the area. The epidemiological implications of these observations in the control of dracunculiasis in South Eastern Nigeria are stressed.

Keywords: cyclopoid copepods, infection rate, relative abundance, dracunculiasis, Nigeria

International Journal of Natural and Applied Sciences Vol. 1(1) 2005: 40-45