Parasitic infections

Entamoeba histolytica life cycle

Parasitic infections refer to diseases caused by parasitic organisms that live and reproduce within or on a host organism, usually causing harm. Parasites can be broadly categorized into protozoa (single-celled organisms) and helminths (worm-like parasites). These infections are a significant cause of morbidity and mortality worldwide, especially in tropical and subtropical regions.

Introduction

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Strongyloides Storcoralis Lifecycle Diagram

Parasitic infections can affect almost any part of the body and are often associated with poor sanitation, contaminated food or water, and vectors like mosquitoes. Many parasites have complex life cycles that involve multiple hosts, stages, and transmission routes.

Classification

Parasitic infections can be classified based on the type of organism:

• Protozoa: Single-celled organisms that often infect the gastrointestinal tract, blood, or tissue.
• Example: Plasmodium spp. (causes malaria), Giardia lamblia (causes giardiasis)

• Helminths: Worm-like organisms which can be further categorized into:
  • Nematodes (roundworms): Such as Ascaris lumbricoides and Enterobius vermicularis.
  • Trematodes (flukes): Such as Schistosoma spp.
  • Cestodes (tapeworms): Such as Taenia solium and Echinococcus granulosus.

• Ectoparasites: Parasites that live on the surface of the host.
  • Example: Lice, ticks, and mites.

Clinical Presentation

The symptoms of parasitic infections vary widely depending on the organism, location, and intensity of the infection. Some common presentations include:

• Gastrointestinal disturbances: Diarrhea, abdominal pain, nausea, or vomiting.
• Fever and systemic symptoms: Seen in infections like malaria.
• Skin manifestations: Rashes, itching, or subcutaneous nodules.
• Organ-specific symptoms: Such as hepatosplenomegaly in schistosomiasis or neurocysticercosis in tapeworm infections.

Many parasitic infections can also remain asymptomatic, especially in endemic areas where repeated exposures can lead to partial immunity.

Diagnosis

Diagnostic methods vary based on the suspected parasite:

• Microscopic examination: Detection of parasites, eggs, or cysts in samples such as stool, urine, or blood.
• Molecular tests: PCR for detecting parasite DNA.
• Serology: Detection of antibodies against the parasite.
• Imaging: X-rays, CT scans, or ultrasounds to detect organ damage or large parasites.

Treatment

Treatment often involves anti-parasitic medications tailored to the specific organism, alongside supportive care. Some commonly used drugs include:

• Metronidazole for protozoal infections.
• Praziquantel for trematode and cestode infections.
• Albendazole or mebendazole for nematode infections.

Prevention

Prevention strategies depend on the type and mode of transmission of the parasite:

• Improved sanitation and access to clean water.
• Use of insect repellents, bed nets, and appropriate clothing in areas with vector-borne transmission.
• Regular deworming in endemic areas.
• Proper food storage, preparation, and cooking.

List of parasitic infections

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

a

• acanthamoeba infection -

• african sleeping sickness - (trypanosomiasis, sleeping sickness)

• alveolar hydatid disease - (echinococcosis)

• amebiasis - (entamoeba histolytica infection)

• american trypanosomiasis - (chagas disease)

• ancylostoma - infection - (hookworm infection, cutaneous larva migrans, clm)

• angiostrongylus - infection - (angiostrongyliasis)

• angiostrongyliasis - (angiostrongylus infection)

• anisakis infection - (anisakiasis)

• anisakiasis - (anisakis infection)

• ascariasis - (intestinal roundworms)

---

b

• babesia - infection - (babesiosis)

• babesiosis - (babesia infection)

• balantidiasis - (balantidium infection)

• balantidium - infection - (balantidiasis)

• baylisascaris - infection - (racoon roundworm)

• bilharzia - (schistosomiasis)

• blastocystis hominis - infection

• body lice -

---

c

• capillaria - infection - (capillariasis)

• capillariasis - (capillaria infection)

• cercarial dermatitis - (swimmer's itch)

• chagas disease - (american trypanosomiasis)

• chilomastix mesnili

• clonorchis - infection - (clonorchiasis)

• clonorchiasis - (clonorchis infection)

• clm - (cutaneous larva migrans, hookworm infection) - (pubic lice)

• cryptosporidiosis - (cryptosporidium infection)

• cryptosporidium - infection - (cryptosporidiosis)

• cutaneous larva migrans -, clm (hookworm infection, ancylostoma infection)

• cyclospora - infection - (cyclosporiasis)

• cysticercosis - (neurocysticercosis)

---

d

• delusional parasitosis -

• dientamoeba fragilis - infection -

• diphyllobothrium - infection - (diphyllobothriasis)

• dipylidium - infection - (dog or cat tapeworm infection)

• dracunculiasis - (guinea worm disease)

• dog tapeworm - (dipylidium)

---

e

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

• e. Histolytica - infection - (amebiasis)

• echinococcosis - (alveolar hydatid disease)

• elephantiasis - (filariasis, lymphatic filariasis)

• endolimax nana - infection -

• entamoeba coli - infection -

• entamoeba dispar - infection -

• entamoeba hartmanni - infection -

• entamoeba histolytica - infection - (amebiasis)

• entamoeba polecki - infection -

• enterobiasis - (pinworm infection)

---

f

• fasciola - infection - (fascioliasis)

• fascioliasis - (fasciola infection)

• fasciolopsiasis - (fasciolopsis infection)

• fasciolopsis - infection - (fasciolopsiasis)

• filariasis - (lymphatic filariasis, elephantiasis)

• foodborne diseases -

---

g

• giardia - infection - (giardiasis)

• giardiasis - (giardia infection)

• gnathostoma - infection - (gnathostomiasis)

• gnathostomiasis - (gnathostoma infection)

• guinea worm disease - (dracunculiasis)

---

h

• head lice infestation - (pediculosis)

• heterophyes infection - (heterophyiasis)

• hymenolepis - infection - (hymenolepiasis)

• hookworm infection - (ancylostoma infection, cutaneous larva migrans)

---

I

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

• intestinal roundworms - (ascariasis)

• iodamoeba buetschlii - infection -

• isospora - infection - (isosporiasis)

---

l

• leishmania - infection -(leishmaniasis, kala-azar)

• leishmaniasis - (kala-azar, leishmania infection)

• lice - (body lice, head lice, pubic lice)

• loa loa infection - (loaiasis)

• lymphatic filariasis - (filariasis, elephantiasis)

---

m

• malaria -

• microsporidia - infection - (microsporidiosis)

---

n

• naegleria - infection -

• neurocysticercosis - (cysticercosis)

• nonpathogenic intestinal amebae infection -

---

o

• onchocerciasis - (river blindness)

• opisthorchis - infection - (opisthorchiasis)

---

p

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

• paragonimus - infection - (paragonimiasis)

• pediculosis - (head lice infestation)

• pinworm infection - (enterobiasis)

• pneumocystis carinii - pneumonia - (pcp)

• pubic lice - ("Crabs")

---

r

• raccoon roundworm infection - (baylisascaris infection)

• recreational water -

• river blindness - (onchocerciasis)

---

s

• scabies - (mite infestation)

• schistosomiasis - (bilharzia)

• sleeping sickness - (trypanosomiasis, african sleeping sickness)

• strongyloides - infection - (strongyloidiasis)

• swimmer’s itch - (cercarial dermatitis)

• swimming pools -

---

t

• taenia - infection - (tapeworm infection)

• tapeworm infection - (taenia infection)

• toxocara - infection - (toxocariasis, ocular larva migrans, visceral larva migrans)

• toxocariasis - (toxocara infection, ocular larva migrans, visceral larva migrans)

• toxoplasmosis - (toxoplasma infection)

• trichinellosis - (trichinosis)

• trichinosis - (trichinellosis)

• trichomonas - infection - (trichomoniasis)

• trichomoniasis - (trichomonas infection)

• trichuriasis - (whipworm infection, trichuris infection)

• trichuris - infection - (whipworm infection, trichuriasis)

• travelers' diarrhea -

• trypanosomiasis - (african sleeping sickness, sleeping sickness)

---

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

w

• waterborne diseases -

• whipworm infection - (trichuris infection, trichuriasis)

---

z

• zoonotic diseases - (diseases spread from animals to people)

Conclusions

Parasitic infections remain a significant global health challenge, particularly in resource-limited settings. Improved diagnostics, effective treatments, and prevention strategies are crucial in managing and reducing the burden of these infections.

See Also

• Malaria
• Giardiasis
• Schistosomiasis
• Tapeworm infections

External Links

• Centers for Disease Control and Prevention - Parasites
• World Health Organization - Neglected Tropical Diseases

Parasitic infections Resources
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