MICROFILARIAL LOAD IN ANTERIOR SEGMENT OF EYE - PARAMETER OF INTENSITY OF ONCHOCERCIASIS

  • 1 January 1977
    • journal article
    • research article
    • Vol. 55  (6) , 731-737
Abstract
The presence of microfilariae of Onchocerca volvulus in the eye is associated with an increased risk of deterioration of existing eye lesions. An ophthalmological and parasitological examination of 630 persons was performed in a hyperendemic focus of onchocerciasis in northern Togo. The prevalence of microfilariae increased in the cornea as well as the anterior chamber up to the age of 40-50 yr, then decreased. The prevalence of onchocercal punctate keratitis showed a peak for the age group 10-20 yr. In 2/3 of the cases microfilariae were present in the anterior chamber as well as in the cornea. The relative distribution of microfilariae between the anterior chamber and the cornea did not change with the development of severe anterior lesions but in cases with severe posterior lesions relatively more microfilariae were found in the anterior chamber than in the cornea. In all cases of severe ocular lesions the numbers of microfilariae both in the anterior chamber and in the cornea were increased. The average number of microfilariae in the eye can be used as a parameter to enumerate the severity of ocular onchocerciasis.