L18: Blood and Tissue Nematodes

Question 1

What are filarial worms

Answer 1

thread like parasitic roundworms

transmitted by anthropods

cause filarisis

minor ones are: loa loa and mansoella

mostly in africa, asia south america - hot places

Question 2

What is the general life cycle

Answer 2

all very simialr

females are oviviparious and prodiuce microfilaroa

microfili are small thread like larvae that infect the arthopods

humans blood swelling => sheathed
human tissue swelling => unseathed

can stay for years

Question 3

Explain periodicity

Answer 3

microfilaria are in peripheal blood the numbers increase at peak biting times of insect vector

they can accumilate in vesses of lung and liver, important diagnostic factor

Question 4

What are the 4 types of periodcity

Answer 4

1. Nocturnal periodicity: Microfilariae are present in greatest numbers in the peripheral blood during night hours
2. Diurnal periodicity: Microfilariae are present in greatest numbers in the peripheral blood during day hours
3. Nocturnal subperiodicity: Microfilariae are present in the peripheral blood 24 hours a day, with slightly higher numbers
   during night hours
4. Diurnal subperiodicity

Question 5

Clinical Presentation of Bancroftian filariasis

Answer 5

males: lympatic glands of groun and epidymous swell

females: … of labial and mammary glands

disease from living/disintergrating or dead worms in regional areas they can be asymptomaitc in inhibuation, acute inflammarory of chronic obstructive

severe cases cause build of tissue called elelphantaisis and hydrocele

Question 6

stopped at slide 10

Question 7

What is brancroftian filariasis caused by

Answer 7

Prescence of living/degenerating and dead worms in regional arrays they can be asymptomatic, acute inflammatory of chronic
Severe cases may cause elphantites => secondary infection OR
Hydrocele

Question 8

How do you diagnosis brancroftian filariasis/ treatment

Answer 8

History, microfillary during periodicity treatment with DEC or albe/ivor

Question 9

Why is B.crofti unique

Answer 9

Only parasitic inn humans, greatest contributor to lymphatic filariasis
Burgia can also infect monkeys/cats

Question 10

What is Dirofilaria immit

Answer 10

Vector borne filariasis nematodes associated with carnivorous hoses
Dogs/cats
Causes dog heartworm/dirofilariasis
US/Canada problem, risk during mosquito feeding times

Question 11

Clinical presentation of D.immitis in Dogs vs Cats

Answer 11

Dog heart with worms, tired, collapsing can lead to heart failure, breathing problems, weight loss

Die faster cause not natural host, have lower burden => heart and lung failure

Question 12

D.immitis in man’s

Answer 12

Not natural host usually larva doesn’t survive but the dead worms cause lung granulomas and nodules in other tissues
Cause ocular dirofilarires

Question 13

How to diagnose and treat D.immiti

Answer 13

Dogs/cats: see signs, extras for humans see granules and pulmonary lesions

Treatment in dogs: Iver or Doxy
Cats: nothing
Humans: remove granules

Question 14

What is onchocera volvulus

Answer 14

Causes river blindness, humans are only host
Infects black flies
Adult worm in onchocercomas
Microfilaria can migrate and cause other issues

Question 15

What are onchocermomas

Answer 15

Subcutaneous nodules that form when worm becomes encapsulated in subcutaneous tissue produced from host inflammatory response

Question 16

Clinical presentation of Onchocerciasis

Answer 16

Disease from host inflammatory response

Nodules in different body parts, firm smooth rubbery with microfiliaires

Skin disease
Allergic reaction to microfilaries, dermatites, wrinkled, depigmended cracked

Blindness
Invade cornea cause cause inflammation => fibrous tissues
Slowly become blind

Question 17

What is significant about Onchocerciasis

Answer 17

Low socioeconomic areas, NTD

Question 18

Diagnosis and treatment of Onchocerciases

Answer 18

Clinical signs, do skin snips to see worms

Use ivermectin to paralyse the worm so it can’t evade other places so the host immune system can kill it but if encased in ochoromoas then doesnt work

Question 19

What is D.medinensis

Answer 19

Tissue nematode cause dranculciase / Guinea worm disease, almost eradicated

Long thin but NOT TRUE filariel

Female larger than male

Humans are definitive host but can infect mets, intermediate hosts are Copepod crustaisans

Question 20

Clinical signs of Dracunculiasis

Answer 20

Symptoms come after a year, an ulcer forms as the worm emerges cause secondary infections like Tetanus, gangrene

If the join is involved it can become arthritic

Question 21

Diagnosis and Treatment of Dracunculiasis

Answer 21

Pour water on ulcer so rhabidform larvae come out no species drugs just remove it
1, water
2. Use stick to wind it out without breaking it which will release larva in tissue
3. Antibiotics
4. Pain relievers

Question 22

How to control Dracunculiasis

Answer 22

CLEAN WATER, vector control, make sure ur dogs dont bring it home
Worm filter cloth
Cope code crustacean /fish make sure dogs dont eat it