PARA-PREFI

• Parastrongylus cantonensis


  Also known as Rat lungworm
• Parastrongylus cantonensis


  • First described in Canton, China by Chen in 1935 from domestic rats
  • Accidental host: Man
  • Habitat: CNS-brain
  • Diagnostic stage: adult worms
  • Infective stage: L3
  • Source of ex. to inf.: food borne
  • Mode of transmission: Ingestion
• Parastrongylus cantonensis causes acute severe intermittent occipital or bitemporal headache
• Diagnosis of Parastrongylus cantonensis infection requires travel history, CSF analysis, CT scan
• Drugs of choice for Parastrongylus cantonensis

  Mebendazole, Albendazole, Thiabendazole and Ivermectin
• Parastrongylus cantonensis male


  • 16 to 19 mm
  • Kidney shaped, single-lobed bursa
• Parastrongylus cantonensis female


  • 21 to 25 mm
  • "barber's pole" uterine tubules (uterine tubules wound spirally around the intestines)
• Toxocara canis & Toxocara cati

  Cat or Dog Ascaris aka Ascarids
• Toxocara spp. cause Visceral Larva Migrans (VLM) and Ocular Larva Migrans (OLM)
• Mode of transmission for Toxocara spp.

  Ingestion of embryonated eggs
• Toxocara spp. are zoonotic diseases
• Visceral Larva Migrans (VLM)

  • Migration and death of larvae to tissues and organs
  • Inflammation and eosinophilic granulomas
  • Liver, lungs, CNS, eyes
• Ocular Larva Migrans (OLM)


  • May coexist with VLM
  • Unilateral visual impairment
  • Strabismus (duling)
  • Blindness (most serious)
• Trichinella spiralis


  Trichina worm, Muscle worm, Great imitator
• Trichinosis, Trichiniasis, Trichinelliasis


  Diseases caused by Trichinella spiralis
• Trichinella spiralis adult


  • Male: 1.5 mm x 0.04 mm; Female: 3.5 x 0.06mm; Slender anterior end w/ a small orbicular non papillated mouth; Posterior end is bluntly rounded in female and ventrally curved w/ 2 lobular caudal appendages in male
• Trichinella spiralis larvae


  • Spear-like burrowing tip at its tapering anterior end
• Trichinella spiralis females can produce up to 1500 larvae per day
• Symptoms of Trichinella spiralis infection include eosinophilia, edema, muscular pain and tenderness, fever, headache, weakness
• Pathology of Trichinella spiralis

  • Intestinal lesions caused by adult worm
  • Edematous muscle caused by encysted larvae in between striated muscle
• Diagnosis of Trichinella spiralis infection requires serologic test, CBC (eosinophilia), ESR, muscle enzyme, muscle biopsy
• Treatment for Trichinella spiralis

  Removal of the encysted larvae, pain relievers, Mebendazole (500 mg TID for 10-14 days), Thiabendazole (25 mg/kg body weight BID for 5-7 days)
• Trichinella spiralis is the most important cause of trichinellosis in humans and is the species most adapted to domestic and wild pigs
• Trichinella britovi is the 2nd most common Trichinella species in humans and infects primarily wild animals in Asia, Europe, Northern Africa and Western Africa
• Trichinella nativa infects primarily wild carnivores in the frigid zones in Asia, North America, and North Eastern Europe
• Dracunculus medinensis


  Fiery serpent of Israelites; Guinea Worm, Dragon worm
• Dracunculosis/ Dracunculiasis


  Disease caused by Dracunculus medinensis
• Dracunculus medinensis


  • Adult female worm measures up to one meter in length, male measures about 2 cm
  • Vector: Cyclops
• Symptoms of Dracunculus medinensis infection include erythema, tenderness, blister formation, vomiting, diarrhea, asthmatic attacks
• If the Dracunculus medinensis worm is removed without damage, healing usually occurs without problems. If the worm is damaged or broken, there may be intense inflammatory reaction with possible cellulitis along the worm's migratory tract, which can result in arthritis and synovitis
• Prevention of Dracunculus medinensis involves sanitized drinking water
• Microfilaria of Dracunculus medinensis


  • Small, thin, does not have sheath, nuclei extend to end of tail with last nucleus bigger, tip of tail is blunt, nuclei stain deeply and "run together", found in blood
• Dracunculus medinensis is the longest nematode of man
• Filariae


  Blood feeding arthropod vector-borne nematodes
• Lymphatic filariae


  • Wuchereria bancrofti
  • Brugia malayi
• Subcutaneous filariae


  • Loa loa
  • Onchocerca volvulus
• Serous cavity filariae


  Filariae that causes infection in the abdomen
• Lymphatic filariae


  • Considered one of the most debilitating diseases that is known in man
• Wuchereria bancrofti


  Bancroft's filarial worm
• Bancroftian filariasis


  Disease caused by Wuchereria bancrofti