Biomaterial Database

The transmission of onchocerciasis at a forest village in Sierra Leone. I. Simulium damnosum s.l. biting densities and infection with Onchocerca volvulus at five representative sites. 1990

M J Bockarie, and J B Davies, and M C Thomson, and H G Morgan

Department of Medical Entomology, Liverpool School of Tropical Medicine, U.K.

Previous studies in the forest area of Sierra Leone have shown that transmission of Onchocerca volvulus takes place many kilometers away from large breeding rivers and sometimes in open farmland. To determine where and when people in a forest village were most likely to be infected, catches of Simulium damnosum s.l. were carried out every week for 12 months, at five sites in and near a village where onchocerciasis was mesoendemic. The number of flies caught per man a day at open farm sites was significantly higher than the number caught at riverside sites. Infective flies were caught only in farmland and only during the early rainy season. The combined Annual Transmission Potential for the five sites was 129 larvae per man per year. Isoenzyme electrophoresis and morphology of biting flies identified the S. sanctipauli/soubrense subcomplex as the most common vector species. Simulium yahense and S. squamosum were sometimes present. It was concluded that the classical riverside monitoring sites do not represent high risk areas for the transmission of onchocerciasis in a forest village sited well away from the main S. damnosum s.l. breeding sites. The highest risk areas are in open farmland.

UI	MeSH Term	Description	Entries
D007303	Insect Vectors	Insects that transmit infective organisms from one host to another or from an inanimate reservoir to an animate host.	Insect Vector,Vector, Insect,Vectors, Insect
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D008297	Male		Males
D009855	Onchocerciasis	Infection with nematodes of the genus ONCHOCERCA. Characteristics include the presence of firm subcutaneous nodules filled with adult worms, PRURITUS, and ocular lesions.	Onchocerciases
D001947	Breeding	The production of offspring by selective mating or HYBRIDIZATION, GENETIC in animals or plants.	Breedings
D005247	Feeding Behavior	Behavioral responses or sequences associated with eating including modes of feeding, rhythmic patterns of eating, and time intervals.	Dietary Habits,Eating Behavior,Faith-based Dietary Restrictions,Feeding Patterns,Feeding-Related Behavior,Food Habits,Diet Habits,Eating Habits,Behavior, Eating,Behavior, Feeding,Behavior, Feeding-Related,Behaviors, Eating,Behaviors, Feeding,Behaviors, Feeding-Related,Diet Habit,Dietary Habit,Dietary Restriction, Faith-based,Dietary Restrictions, Faith-based,Eating Behaviors,Eating Habit,Faith based Dietary Restrictions,Faith-based Dietary Restriction,Feeding Behaviors,Feeding Pattern,Feeding Related Behavior,Feeding-Related Behaviors,Food Habit,Habit, Diet,Habit, Dietary,Habit, Eating,Habit, Food,Habits, Diet,Pattern, Feeding,Patterns, Feeding,Restrictions, Faith-based Dietary
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012424	Rural Population	The inhabitants of rural areas or of small towns classified as rural.	Rural Residence,Rural Communities,Rural Spatial Distribution,Communities, Rural,Community, Rural,Distribution, Rural Spatial,Distributions, Rural Spatial,Population, Rural,Populations, Rural,Residence, Rural,Rural Community,Rural Populations,Rural Residences,Rural Spatial Distributions