Soil-transmitted Helminth (STH)
What are Helminths?
How Much Human Helminthiasis Is There in the World? [D. W. T. Crompton, 1999]
342 helminth species are described to be associated with humans
Some incidental, some have little or no public significance
Helminth ES phylogeny: 20 selected species
Whipworm and roundworm infections
T. trichiura = whipworm
Ascaris = "small intestinal roundworms"
Phylum of Trichuris spp.?
Nematoda
Whipworm and roundworm infections (life cycles)
How do Trichuris larvae hatch (schlüpfen) from an egg?
Larval Hatching: When the infective larvae are fully developed, they hatch from the eggs.
—> bacterial triggered eg hatching in the small/large intestine
are helminths inhabited by bacteria/symbionts?
e.g. Wolbachia (bacterial endosymbiont) distribution in somatic tissues of mosquitos, flies and worms (green).
Through which organs do A. lumbricoides larvae migrate?
gastroinsetinal tract ,lumen, small intestinal ,lungs, liver
Which factors contribute to the risk of STH infections?
risk factors
Whipworms (pathology)
Ascaris lumbricoides (pathology)
DALY
Disability- Adjusted Life Years (DALY = YLL +YLD)
YLL: Years of Life Lost due to premature mortality
YLD: Years Lived with a Disability
Which drug classes are efficient against Ascarids and Trichuris spp.?
What are current strategies for STH control?
Mass drug administration (MDA) programs
Current challenges
Last changeda year ago
