tissue nematodes

Question 1

what are the general characteristics of nematodes(6)

Answer 1

1. parasitize human blood, lymphatic or skin
2. threadlike worms that may live in host tissues for several years
3. produce tiny microfilarial larvae that circulate in blood & lymphatics
4. they have a biphasic life cycle that alternates between humans and blood sucking mosquito ( fly vector)
5. Adult filaraiae live in various human tissue locations and produces living embryos
6. All rewuire arthropod intermediate host for transmission of infection

Question 2

Name the four tissue nematodes that causes filariases

Answer 2

1. Wucheria Bacroofti ( Bancroft’s filaria)
2. Brugia malayi (malayan filaria)
3. Loa Loa ( eyeworm)
4. Onchocerca volvulus ( blinding filaria)

Question 3

Which 2 out of the 4 nematodes are found in the lymphatic system in the adult form

Answer 3

1. Wuchereria bancrofti

2. Brugia Malayi

Question 4

Which of the 4 nematodes are found in the subcutaneous tissue

Answer 4

1. Loa Loa

2. Onchocerca volvulus

Question 5

What is the vector for Wuchereria bancrofti

Answer 5

Female Culled ( Anapheles mosquito)

Question 6

Nmae the vector for Brugia malayi

Answer 6

Monsonia Anaphele mosquito

Question 7

Which of the two parasites cause Elephantiasis

Answer 7

1. Wuchereria bancrofti

2. Brugia Malayi

Question 8

Name the vector for Loa Loa worm

Answer 8

Chrizops fly - causes blindness

Question 9

which parasite is known as the Blinding filaria

Answer 9

Onchocerca volvulus

Question 10

Name the vector for the Onchocerca Volvulus

Answer 10

Similian fly - also known as the black fly

Question 11

what are the symptoms and pathology for both Wuchereia bancrofti and Brugia Malayi

Answer 11

early phase: fever and lymphangitis

Chronic phase: Elephantitis - obstruction of lymphatics

Question 12

What are the symptoms for Loa Loa

Answer 12

Localized suncutaneuos edema ( Calabar swelling) - around eye

Question 13

What are the symptoms for Onchocercerca Volvulus

Answer 13

Fibrotic nodules encapsulating adults - blindness occurs from the presence of microfilariae in all ocular structures

Question 14

T/F Dracunculus medinensis is the largest filarial worm

Answer 14

False- it is a round worm not a filarial worm

Question 15

How is the guinea worm effect humans

Answer 15

• begins with ingestion of infected cooped by drinking still untreated water
• the larvae feed into the intestine and penetrate subcutaneous tissue

Question 16

When do symptoms occur during the infection of the guinea worm

Answer 16

first occur after a year - maturation of the female worm

1. allergic reaction of migration occurs
2. Papue developing into a blister that ruptures
3. secondary bacteria infection or reaction to aberrant migration of larvae may cause death