soil-transmitted helminthes yemeng lu. overview infectious agents infectious agents prevalence...
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Overview
Infectious Agents PrevalenceTransmissionHealth ProblemsTreatmentControl
Public health image library database (PHIL) of the US Centers for Disease Control (CDC)
The causal agents of soil-transmitted helminthiasis are three type of worms
Prevalence
Infectious Agents Transmission Health Problems Treatment Control
Ascaris lumbricoides (Roundworms)
Trichuris trichura (Whipworms)
Necator americanus and Ancylostoma duodenale (Hookworms)
Laboratory Identification of Parasites of Public Health Concern Image Library
Prevalence
Infectious Agents Transmission Health Problems Treatment Control
Partners for Parasite Control: Fact Sheet
Severe and heavy helminth infections cause more than 150,000 deaths
annually
Prevalence
Infectious Agents Transmission Health Problems Treatment Control
“Threehundredmillion people areseverely illdue toworms”
Partners for Parasite Control: Newsletter Issue 1
Worm burdens exhibit a highly aggregated (over dispersed) distribution
Certain individuals tend to be predisposed to heavy infections
• Genetics - Chromosome 1,13
• Behavior
• Poverty
Prevalence
Infectious Agents Transmission Health Problems Treatment Control
Soil-Based Helminths are transmitted via two mechanisms: ingestion and
penetration
Prevalence
Infectious Agents Transmission
Health Problems Treatment ControlPartners for Parasite Control: Newsletter Issue 1
Prevalence
Infectious Agents Transmission
Health Problems Treatment Control
A. lumbricoides is the largest of the intestinal nematodes affecting
humans
Soil-transmitted helminthes produce a wide range of intestinal, nutritional and developmental health problems.
Prevalence
Infectious Agents TransmissionHealth Problems
Treatment Control
http://curezone.us/image_gallery/parasites/
STH infections are treatable with anthelmintic drugs ="deworming"
Prevalence
Infectious Agents Transmission Health Problems Treatment
Control
Modified from Helminth control in school-age children
Partners for Parasite Control
The cost of treatment is less than $0.25 per person per year.
STH infections are treatable with anthelmintic drugs ="deworming"
Prevalence
Infectious Agents Transmission Health Problems Treatment
Control
Roundworm
Whipworm
Albendazole impairs the assembly of microtubules in worm cells and
prevent glucose uptake
Albendazole
Tubulin
Assembly into microtubules
Cellular transport mechanisms
Worm intestinal cells
GlucoseRectal Expulsion
Anthelmintic drug treatmentcombined with improved sanitation and
health Education can reduce transmission and infection
Prevalence
Infectious Agents Transmission Health Problems Treatment Control
Helminth control in school-age children
Citation: Hotez PJ, Bundy DA, et al. Helminth Infections: Soil-transmitted Helminth Infections and Schistosomiasis.
In: Jamison DT, Measham AR, Alleyne G, eds. Disease Control Priorities in Developing Countries. 2nd ed. New York, NY: World Bank/Oxford University Press; 2006 Chapter 24.
De Silva N. R., Chan M. S., Bundy D. A. P. Morbidity and Mortality Due to Ascariasis: Re-estimation and Sensitivity Analysis of Global Numbers at Risk. Tropical Medicine and International Health. 1997; 2: 519–28.
Montresor A, Crompton DW, Gyorkos TW, Savioli L, et al. Helminth Control in School-age Children: A Guide for Managers of Control Programmes. Geneva, Switzerland: World Health Organization; 2002: 1-35.
Issue 1: Introduction. Action Against Worms. Partners for Parasite Control. March 2003. Fact sheet: Soil-transmitted helminthes. World Health Organization.
http://www.who.int/wormcontrol/documents/fact_sheets/soil_transmitted_helminths/en/index.html; 2010; April 2nd 2010.
Schmidt J. Effects of benzimidazole anthelmintics as microtubule-active drugs on the synthesis and transport of surface glycoconjugates in Hymenolepis microstoma, Echinostoma caproni, and Schistosoma mansoni. Parasitology Research. 1998 May;84(5):362-8.
Roos MH, Kwa MS, Veenstra JG, Kooyman FN, Boersema JH. Molecular aspects of drug resistance in parasitic helminths. Pharmacology & Therapeutics. 1993 Nov;60(2):331-6.
Lacey E. The role of the cytoskeletal protein, tubulin, in the mode of action and mechanism of drug resistance to benzimidazoles. International Journal for Parasitology 1988 Nov;18(7):885-936.
Ascariasis, Parasite and Health; Laboratory Identification of Parasites of Public Health Concern, Center for Disease Control; http://www.dpd.cdc.gov/dpdx/html/Ascariasis.htm; July 2009; April 2nd 2010.