Prevalence of lymphatic complications due to onchocerciasis infection in Imo State, Nigeria

Abstract

The study was conducted to determine the prevalence of lymphatic complications due to onchocerciasis infection in 38 endemic rural communities in the Imo River Basin, Nigeria. Using standard parasitological and clinical methods of diagnosis, 7,144 consenting individuals aged 5 years and above were examined for Onchocerca volvulus microfilaria and clinical lymphatic symptoms of onchocerciasis. Of the 7,144 individuals, examined, 1,646 (23.0%) were positive for O. volvulus microfilariae, while 1,045 (14.6%) had various degrees of lymphatic complications. The prevalence of lymphatic complications were lymphadenopathy (7.9%), hanging groin (3.2%) and inguinal hernia (3.5%). Subjects 30 years and above had the highest microfilarial densities which coincided with higher prevalences of these lesions suggesting their chronicity. Sex-prevalence showed an insignificant borderline difference, 17.3% in males and 14.3% in females (p > 0.05). Lymphadenopathy and hanging groin were strongly associated with microfilarial density (r = 0.54; p<0.001) and (r = 0.59; p<0.001) respectively. The study shows that lymphadenopathy, hanging groin and inguinal hernia are lymphatic manifestations of onchocerciasis in the rain-forest. Their chronic and irreversible nature however creates a strong imperative for their prevention/control by the use of an annual dose of ivermectin..

Keywords:Onchocerciasis, lymphatic complications, prevalence, ivermectin, Imo River Basin, Nigeria.

Nigerian Journal of Parasitology Vol. 27 2006: pp. 23-28