The endemicity of dracunculiasis, transmission pattern and ecology of cyclopoid copepods in the Northwestern part of Ebonyi State, Nigeria

Abstract

Studies on the endemicity of dracunculiasis, it's transmission pattern and ecology of cyclopoid copepods in Ezza North Local Government Area of Ebonyi State Nigeria were carried out between January and December 2001. Of the 2226 persons examined in eight communities, 426 (19.1%) were infected. This included 24 (18.3%) and 202 (20.2%) males and females respectively. The highest prevalence (47.9%) was recorded in Iyere community followed by Ekka (43.9%) with Umuoghara community as the least (12.4%). Although the overall male prevalence was lower than the female, it was not statistically significant (p>0.05). Infection prevalence in school-aged children (1-24 years) was significantly higher than the older persons (p<0.05) and 98 (26.0%) drank from fifteen small natural ponds and sixteen small man-made ponds respectively. The epidemiological pattern of dracunculiasis transmission in Ebonyi showed that infection is mainly during the dry season when virtually all subjects depend on pond water. The period of high Cyclops densities corresponded to the period of mean monthly rainfall of less than 26 cm. High density of Cyclops was recorded during the dry season periods when the water volume is relatively low. Infestation of the various ponds varied. Six species of cyclopoid copepods were identified in this study. The commonest copepod was Mesocyclops aequatorialis, which accounted for >63% of all the copepods found. This was followed by Thermocyclops oblongatus nigerianus with M. ogunnus Onabamiro as the least. Only T. oblongatus nigerianus and M.aequatorialis were infected with D. medinensis larvae. The ecology of the vector in relation to the epidemiology of the disease in the area is discussed.

Keywords: dracunculiasis, endemicity, transmission pattern, ecology, cyclops, Nigeria

International Journal of Natural and Applied Sciences Vol. 1(1) 2005: 57-67