Dynamique des schistosomoses intestinales au Cameroun: evolution de la trasmission dans le foyer mixte de Nkolmebanga; Lekie

This study was undertaken to evaluate the current status of shistosomiasis in the Nkolmebanga region (Lekie) of Cameroon; p rev i o u s ly determined to be a mixed zone harboring both Schistosoma mansoni and S. intercalatum. Study invo lved both malacology with collection and identifi c ation of fre s h water snails in four wat e rpools and para s i t o l ogy with collection and analysis of stools from schoolchildren Five species of freshwater snails were identified including two that were intermed i ate host of Schistosomes; i.e.; Biomphalaria pfe i ffe ri and Bulinus fo rskalii. Only B. pfe i ffe ri species collected from the Momboh and Mbonsoh Rivers shed Schistosoma cercaria. A total of 347 schoolchildren were enrolled but only 200 provided stools for parasitological testing. There were 93 boys and 107 girls. Parisitology demonstrated S. intercalatum eggs in the stools of no children. S. mansoni eggs were identified in the stools of 10 children for a prevalence of 5. Parasitic load ranged from 24 to 1104 eggs per gram of stool. In this study both malacologic and parasitological findings suggested that S. mansoni persists in Nkolmebanga region but that S. intercalatum has disappeared probably as a result of deforestation and urbanization

Intergrated control trial of schistosomiasis at Nakiwogo fishing village near Entebbe; Uganda

Using the Kato katzi technique; 600 people living in Nakiwogo fishing village at Lake Victoria; Uganda; were examined for schistosoma mansoni infection. The total population of this village was estimated between 1;00 and 1;500 mainly consisting of migrants from Western Uganda. Of the 600 individuals in the study group; 328 people (54.7) were found to be infected with S. mansoni. The geometric mean egg count was 422 eggs per gramme of stool. a survey of the snail intermediate hosts for S. mansoni and S. haematobium at Nakiwogo was carried out. The collected snails were tested for cercariae shedding. A significant decrease in the number of Biomphalaria choanomphala and Biomphalaria pfeifferi (52) which both still shed cercariae and Bulinus (52.5) could be observed. There was a lower none-significant decrease of 13.3of the Bulinus globosus population. With a combined approach including community participation in control measures in the form of health education; sanitation; environmental management and chemotherapy; the prevalence of S. mansoni infection was reduced from 54.7to 14.6 in the period of one year

Schistosoma mansoni along Lake Alibert; Kibale district; Western Uganda

Four hundred and fifty one human strata living in the three fishing villages of Ndiaga; kabukanga and Rwabikongoro along Lake Albert shore in Kibale District were examined for S. mansoni infection using Kata/Katz method. Of the 451 people; 409(90.7) were found infected with S. mansoni with geometric mean egg count of 561.3 eggs per gram (epg) faeces. Males had significantly higher mean egg counts than females; 608.e epg and 415.6 epg respectively. All S. mansoni infected individuals were treated with praziquantel at 40mg/kg body weight. Other common parasites observed were Ascaris lumbricoides; Trichuris trichiura and hookworms. These were treated with mebandazole. Snail infection rate among the 115 Biomphalaria sudanica and the 56 B. stanleyi were 5.2and 3.6respectively. All the 66 Bulinus (B) tropicus found; were negative for cercariae shedding. The main pulmonate snails were 250 Lymnae natalensis; 500 Pila ovata and 375 Bellamya spp were the commonest prosobranchs followed by Bivalves (101)

A preliminary study on intermediate snail hosts of schistosomes in Reiver enyau; Arua District; Uganda

A total of 1260 snail intermediate hosts of both Schistosoma mansoni and Schistosoma haemotobium were collected along the non-seasonal river enyau which lies half a kilometre west of Arya; north-western Uganda town. The snails collected were Biomphalaria pfeireri 709: Biomphalaria choanomphala 457; Bulinus tropicus 94. These were screened for cercariae shedding and 25 B. pfeifferi and 12 B. choabomphalal shed mammalian cercaricae while none of the Bulinus) tropicus shed any cercae. River enyau Biomphalaria snails were susceptible to a Schistosoma mansoni strain from Entebbe. Cercariae derived from these snails and also those found infected in the River Enyau were confirmed to be S. mansoni using laboratory mice

The intensity of Schistosoma mansoni in the fishing villages of Bugonga and Kitubulu in Entebbe Peninsula; Uganda

The intensity of Schistosoma mansoni infection in the fishing villages of Bugonga and Kitubulu; and the occurrence of snail intermediate host population in the two villages are described and compared. A total of five hundred and six faecal samples from both villages were examined by modified Kato's technique and the prevalence infection rate at Kitubulu was 40.3pc with mean egg count of 187 eggs per gram(epg) while in Bugonga it was 32.4pc and 126 epg respectively. The snail intermediate host for S. mansoni in the two villages was 2;750 Biomphalaria choanomphala at Kitubulu and 1;268 at Bugonga. But at Kitubulu in the vicinity of the village 185 Biomphalaria peifferi occurred in small localized population. The cercarial screening test conducted on 4;018 B. choanomphala and 185 B. peifferi from the two villages revealed higher snail infection rate for both mammalian and non-mammalian cercariae at Kitubulu than Bugonga. Variations in infection rates both among the inhabitants and host snail populations in the two villages are discussed