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Determining Soil-transmitted Helminth Infection Status and Physical Fitness of School-aged Children
Published on: August 22, 2012
The "crowding effect" phenomenon in Ascaris lumbricoides
R B Monzon1, B D Cabrera, A C Cruz
1Department of Parasitology, College of Public Health, University of the Philippines, Manila.
The Southeast Asian Journal of Tropical Medicine and Public Health
|December 1, 1990
Summary
The crowding effect, previously observed in tapeworms, also impacts Ascaris lumbricoides. Increased worm burden in children led to significantly lighter individual worms, suggesting resource competition.
Area of Science:
- Parasitology
- Helminthology
- Public Health
Background:
- Ascariasis, caused by Ascaris lumbricoides, is a prevalent soil-transmitted helminthiasis globally.
- Understanding factors influencing worm burden and parasite physiology is crucial for effective control strategies.
Purpose of the Study:
- To investigate the relationship between worm burden and individual worm weight in Ascaris lumbricoides.
- To determine if the "crowding effect" phenomenon, known in other helminths, applies to Ascaris lumbricoides.
Main Methods:
- Study involved 150 Filipino children (0-14 years) treated with pyrantel pamoate or oxantel-pyrantel pamoate.
- Collected adult Ascaris lumbricoides worms (n=2072) were sexed and weighed.
- Statistical analyses included descriptive statistics, one-way ANOVA, and linear regression to assess worm weight in relation to infection intensity.
Main Results:
- Mean weights of male and female Ascaris lumbricoides significantly decreased as worm burden increased.
- Linear regression analysis confirmed this inverse relationship, even after accounting for host factors.
- The findings suggest a "crowding effect" impacting individual worm growth.
Conclusions:
- The "crowding effect" phenomenon is demonstrated in Ascaris lumbricoides populations.
- This has implications for understanding parasite biology and the dynamics of ascariasis in endemic areas.
- Further research into resource competition within Ascaris lumbricoides infections is warranted.
