Blood and tissue nematodes Flashcards
General Characteristic of Blood and tissue nematodes.
Not common in U.S.
Often from eating undercooked beef, fish, pork
Man often an accidental or intermediate host
Common name for Trichinella spp.
Trichinosis
Usually caused by ingestion of raw/undercooked Pork, bear and other meat.
Trichinella spp.
Life cycle of Trichinella spp.
Larvae released in intestines –> encapsulate in striated muscle (active muscles, eye, diaphragm)
Clinical Manifestations of Trichinella spp.
Few symptoms while intestinal phase (diarrhea, abdominal discomfort)
Triad of symptoms:
-Periorbital edema, muscle pain & tenderness, eospinophilia.
Trichinella spp. : Diagnosis
Muscle biopsy (encysted larvae)
- squash prep (spiral form)
- Cross-sectioned mounts
Is stool specimen choice of the blood and tissue nematodes?
NOOOOO
Common name for Dracunculus medinensis.
Guiney worm
Largest adult Nematode
Dracunculus medinensis
Life cycle of Dracunculus medinensis.
Humans ingest copepod (cyclops spp)–> female migrates to surface of arm/leg to release larvae into water–> larvae ingested by copepod
Drancunculus medinensis: Diagnosis
Blister like papula on arm/leg
very painful/debilitating-while female discharge larvae
NO STOOL
Treatment of Drancunculus medinensis
Winding worm around stick
secondary infection is common if breakage of worm occurs
Prevention of Drancunculus medinensis
Filtration of water to remove copepods and covering water source from copepods and infected people
This is normally found in raccoons and common in the United States.
Baylisascaris procyonis
Treatment and diagnosis of Baylisascaris procyonis
No known treatment and diagnosis usually on autopsy
This is very serious zoonotic in humans, esp children and very resistance so have to spray with acetone and xylene.
Baylisascaris procyonis
Diagnosis of Baylisascaris procyonis infection
Epidemiology (exposure to raccoons??) and larvae in tissue sections . Potential biological warfare agent!!!!
Adults living in various lymphatic or other tissues.
Filariae
Microfilariae (larvae) released in _____.
Blood
Common name is Bancroftian filariasis or elephantiasis.
Wuchereria bancrofti
What is the vector of Wuchereria bancrofti & Brugia malayii?
Mosquito
Clinical manifestations of Wuchereria bancrofti.
Swelling of genitalia and/or lower extremities (lymphatics)
chronic infections lead to elephantiasis
Life cycle of Wuchereria bancrofti & Brugia malayii.
Adults live in lymphatics-> obstruction of lymphatics (esp. lower extremities)
Female worms release microfilariae into blood that ingested by mosquito where the parasite completes it’s life cycle.
Diagnosis of Wuchereria bancrofti.
Microfilariae are sheathed, no nuclei at tip of tail, cephalic space
Common name is Brugian filariasis or elephantiasis
Brugia malayi
Clinical manifestation of Brugia malayii.
distal extremity involvement (below elbow and knee)
Diagnosis of Brugia malayii.
Microfilariae are sheathed, space between last two nuclei at tip of tail, cephalic space
Common name for Loa loa
African eyeworm
What is the vector of Loa loa?
Fly
Clinical manifestations of Loa loa.
Calabar swellings
Life cycle of Loa loa.
adults migrate through subcutaneous tissue (calabar swellings and migration across eye)
Diagnosis of Loa loa.
Microfilariae are sheathed, nuclei continuous to tip of tail.
Common name of Onchocerca vulvulus
Onchocercosis or River blindness
This is most common cause of blindness in Africa
Onchocereca vulvulus
How is Onchocereca vulvulus transmitted?
By black or buffalo fly
Clinical manifestation of Onchocereca vulvulus.
Tumors in subcutaneous tissues, leopard skin, nodules, blindness
Diagnosis of Onchocereca vulvulus
Skin snip; microfilariae are non-sheathed, no nuclei in tip of tail
This is transmitted by midges or blackfly and cause some rash, slight fever, non serious infections.
Mansonella species
This has no microfilariae sheath but have to differentiate from Onchocerca by position of nuclei.
Mansonella species
Common name of Dirofilaria immitis.
Dog heartworm
Most common in Indiana and vector is mosquito.
Dirofilaria immitis
____ live in chambers of dog’s heart (infraction). ____ in blood.
Adults; microfilariae
Flattened dorsoventrally
Lice
Flattened laterally, Large hind legs for jumping, 3 pair of clawed legs, and transmit bacterial infections
Fleas
Three types of louse.
Body, head, pubic louse
This is Pediculus humanus, nits deposited clothing, transmitted host to host
Body louse
This is Pediculus capitus, Nits found on hair, and use wood lamp to fluoresce
head louse
This is Phthiris pubis, and microscopically carbs.
Pubic louse
This has chitenous shield, mouth parts attached to fused body, 4 pair legs in adults (3 in larvae) and usually transmits diseases (RMSF, Lyme, Babesiosis)
Ticks
No chitenous shielf, have short legs, burrows in skin and lays eggs.
Mites
Causes scabies due to host to host crowded coniditons and poor hygienes
Mites
Types of Arachnida.
Ticks, mites, spiders, and scorpions
