Formol Gel detection of Leishmanial Antibodies: A Pilot Study for the prevalence of Visceral Leishmaniasis in Ekemkpon Community in Odukpani Local Government Area of Cross River State, Nigeria

Abstract

Visceral leishmaniasis is a form of parasitic infection transmitted to human beings by the bites of female sandflies of the genus Phlebotomus in African  countries, including Nigeria. This study was carried out in Ekemkpon community of Cross River State in Southern Nigeria, as a survey for the presence of  leishmanial antibodies in the area. Four millilitres of blood specimens were collected, by venepuncture, from 178 consenting residents of the study  community. One millilitre of cellfree serum from each blood specimen was placed in a plain test tube, to which 2 drops of concentrated formalin (40%)  were added. The preparation was allowed to stand on the bench for 20 minutes. A positive Formol Gel test was indicated by the whitening and gelling of  the serum like the white of an egg within 5 minutes, Chi-Square technique was used for testing the statistical significance of all parameters during  analysis. Atotal of 178 residents, comprising 95 males and 83 females, were enlisted in the study after obtaining their oral consent. Positive formol gel  results were detected in 24 subjects. This finding gave an overall prevalence of 13.5% (24:178) for visceral leishmaniasis in the study area. Among the  residents of the study area, there were no skin manifestations suggestive of cutaneous forms of leishmaniasis. Among those who were positive for the  formol gel test, there were no overt signs of classical illness. Therefore, visceral leishmaniasis exists as an asymptomatic infection in this community. It is  recommended that more sensitive tests, especially molecular techniques, be carried out for a definitive diagnosis to establish the presence or absence of  visceral leishmaniasis in this community.