Parasitic infections of the intestines

P C Okhuysen1, A C White

  • 1Division of Infectious Diseases, Department of Internal Medicine, University of Texas Medical School, Baylor College of Medicine, Houston, Texas 77030, USA.

Insights

Intestinal parasites like protozoans and helminths are common globally, causing diarrhea in children and impacting nutrition. Mass chemotherapy is a key control strategy in developing nations.

Area of Science:

  • Global Health
  • Infectious Diseases
  • Parasitology

Background:

  • Intestinal parasites are a major global health concern, particularly in developing countries.
  • Intestinal protozoans are significant causes of childhood diarrhea.
  • Cryptosporidiosis, while decreasing in AIDS patients due to antiretroviral therapy, remains a concern.

Purpose of the Study:

  • To review the prevalence and impact of common intestinal parasites worldwide.
  • To highlight the ongoing challenges posed by food and waterborne parasitic outbreaks.
  • To discuss current strategies for controlling intestinal helminth infections.

Main Methods:

  • Review of existing epidemiological data on intestinal parasite prevalence.
  • Analysis of factors contributing to outbreaks of Cryptosporidium, Cyclospora, and Giardia.
  • Examination of the impact of helminth infections on host health.
  • Assessment of disease control strategies, including mass chemotherapy.

Main Results:

  • Intestinal protozoans cause significant childhood diarrhea in developing countries.
  • Cryptosporidium, Cyclospora, and Giardia outbreaks are linked to contaminated food and water.
  • Ascaris, hookworm, and Trichuris each infect over a billion people.
  • Parasitic infections can have subtle but significant effects on cognitive function and nutrition.

Conclusions:

  • Intestinal parasites continue to be a widespread health issue globally.
  • Contaminated food and water remain key sources for parasitic outbreaks.
  • Mass chemotherapy is a primary approach for controlling helminth infections in endemic areas.

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