Culicoides spp. (2)

Question 1

What are the common names?

Answer 1

Biting midges

No-see-ums

Question 2

What are the hosts?

Answer 2

Any animals

Humans

Question 3

Describe adults

Answer 3

1.5-5 mm long

Short piercing proboscis

Wings

 - Mottled
 - Held like a closed pair of scissors over abdomen

Antenna long and slender

800 species

Question 4

Explain life cycle

Answer 4

Associated with aquatic or semi-aquatic habitats
- Mud, moist soil around streams, ponds, marshes

Eggs laid in damp marshy ground

4 instar stages

Pupa

Adults

Slightly longer life cycle

Question 5

What are the sites of infection?

Answer 5

Anywhere on animal

Question 6

Describe the Pathogenesis

Answer 6

Only females fed - suck blood, inflict painful bites
- Intense irritation and annoyance

Horses become allergic

 - Scratching, rubbing
 - Cause:
        - Alopecia
        - Excoriations
        - Thickening of skin
 - Known as:
        - Culicoid hypersensitivity - Canada
        - Queensland itch - Australia 
        - Kasen - Japan
        - Sweat itch, sweet itch, Summer dermatitis 

Transmit African Horse Sickness (AHS)

IH for Onchocerca cervicalis - Mff found on skin of horses

Transmit blue tongue virus in sheep and cattle

Question 7

How do you diagnose?

Answer 7

Fly identification

Question 8

How do you treat and prevent?

Answer 8

Difficult to control with insecticides (must have rapid killing or repellant ability)

Control difficult
     - Extensive breeding habitats
     - Depends on destruction of breeding sites by drainage or spraying 
        insecticides
     - Decrease standing water
     - Avoid marshy areas

Question 9

What is important about Culicoides spp.?

Answer 9

It is ZOONOTIC