Protozoa: Characteristics and Diseases

Protozoa

• Unicellular eukaryotic organisms with complex life cycles, contributing to diverse ecological roles.
• Reproduce through sexual and asexual methods; motility is achieved via flagella, cilia, or amoeboid movement.
• Asexual reproduction methods include:
  • Binary fission: a single organism divides into two equal parts.
  • Schizogony: multiple divisions occur before cell division, producing many offspring simultaneously.
• Sexual reproduction involves:
  • Gametogony: formation of gametes.
  • Conjugation: exchange of genetic material between organisms.
• Significant intestinal protozoa impacting human health:
  • Entamoeba histolytica: causes dysentery.
  • Balantidium coli: linked to gastrointestinal distress.
  • Giardia lamblia: causes giardiasis, leading to diarrhea.
  • Trichomonas vaginalis: sexually transmitted infection causing vaginitis.
  • Cryptosporidium parvum: causes cryptosporidiosis, resulting in watery diarrhea.
  • Isospora belli: associated with opportunistic infections, especially in immunocompromised individuals.
• Diseases from protozoan infections can range from mild gastrointestinal disturbances to severe conditions like liver abscesses.

Helminthes (Worms)

• Classified into three main groups:
  • Nematodes (roundworms)
  • Trematodes (flukes)
  • Cestodes (tapeworms)
• Trematodes include:
  • Liver flukes, intestinal flukes, blood flukes, and lung flukes.
  • Schistosoma species cause schistosomiasis, a significant health issue in endemic areas.
• Cestodes examples:
  • Taenia saginata (beef tapeworm) leads to taeniasis.
  • Hymenolepis nana (dwarf tapeworm) causes hymenolepiasis, particularly in children.
• Nematodes examples:
  • Enterobius vermicularis (pinworm) leading to enterobiasis, common in children.
  • Ascaris lumbricoides (roundworm) causes ascariasis, affecting nutrient absorption.
• Wuchereria bancrofti: causative agent of elephantiasis, transmitted through mosquito bites, causing severe lymphedema.

General Treatment

• Treatment strategies vary based on the specific parasite involved:
  • Common medications include:
    • Metronidazole and Tinidazole for protozoal infections.
    • Specific antimalarial drugs integrated based on the malaria parasite type.
• Prevention strategies emphasize:
  • Adopting proper hygiene and sanitation practices.
  • Avoiding ingestion of contaminated food and water to decrease infection risk.