Recent Examination for Assessing Epidemiological Status of Schistosoma Mansoni in Plaine Orety, Urban Area of Libreville, Gabon, Central Africa

Schistosoma mansoni epidemiology is very uncertain in Gabon despite its wide distribution in Sub-Saharan African whereas knowledge of schistosomiasis endemicity setting has important implications for the national policy controls. To date only two cases of S. mansoni were diagnosed by the Department of Parasitology-Mycology (DPM), Libreville-Gabon between 1995 and 2009 and both came from Plaine Orety, an urban area of Libreville. As the result of this finding a survey that we report results here was conducted to determine the epidemiological status of S. mansoni in this site. Parasitological and malacological surveys were conducted prospectively from January to May 2012. Parasitological survey included people living in Plaine Orety (Libreville) area at least three months and aged from two years upwards. Stool examination was performed using Kato-Katz technique and malacological investigations were conducted in all the streams of this area for the same period to identify the intermediate snail host of S. mansoni. A total of 495 people were examined, of them 4 cases (0.81%) were identified positive to S. mansoni with no significant influence of sex or age group (p>0.05). Infected peoples said they never went out of the country but stayed in other regions of the country, i.e. Kango, Ovan, Lambaréné, Port-Gentil, Bitam and Fougamou. No intermediate snail host of human schistosomes has been identified in the whole surveyed water sites of Plaine Orety. Freshwater snails identified are: Lymnea sp, Physa sp, Melanoides sp and Indoplanorbis exustus (intermediate snail host of cattle schistosomes in India). The finding of this study illustrate existing indigenous cases of S. mansoni in Libreville (Gabon) even if local active transmission area remains to be elucidate because of the absence of intermediate snail host Biomphalaria