Myiasis

Question 1

1. Species?
2. How to identify?
3. Reasons?
4. How to prevent infestation?
5. Geographic distribution?
6. Clinical presentation

Answer 1

1. Cochliomyia hominovorax
2. Examine posterior spiracles
3. Features:
   * Elongate, screw-shape form
   * Cuticular spines on all body segments
   * Straight slits on spiracular plate
4. Fly avoidance and wound hygiene as flies lay eggs in wounds
5. Central and South America
6. Obligatory wound myiasis where pre-existing wounds are usually colonized

Question 2

1. Species?
2. How to identify?
3. Reasons?
4. How to prevent infestation?
5. Geographic distribution?
6. Clinical presentation

Answer 2

1. Oestrus ovis
2. Examination of morphology (no posterior spiracles)
3. Features:
   * First-instar larvae
   * Prominent mandibular sclerites
   * 3 rows of spines on each body segment
   * Posterior end with 2 scallops and hooks
4. Fly avoidance
5. World-wide in sheep-raising regions
6. Ophthalmomyiasis, upper respiratory tract

Question 3

1. Species?
2. How to identify?
3. Reasons?
4. How to prevent infestation?
5. Geographic distribution?
6. Clinical presentation

Answer 3

1. Lucilia
2. Examine posterior spiracles
3. Features:
   * Straight slits on spiracular plate
   * Complete peritreme but weak in area of button (black arrow)
4. Fly avoidance and wound hygiene as flies lay eggs in wounds
5. Worldwide
6. Facultative myiasis

Question 4

1. Species?
2. How to identify?
3. Reasons?
4. How to prevent infestation?
5. Geographic distribution?
6. Clinical presentation?

Answer 4

1. Cordylobia anthropophaga
2. Posterior spiracles
3. Features:
   * Robust form
   * Cuticular spine on every segment
   * Weak peritreme
   * Sinuous slits
4. Iron clothes before wearing as flies lay their eggs on clothes that are drying
5. Sub-Saharan Africa
6. Furuncular myiasis with nonmigratory boils

Question 5

1. Species?
2. How to identify?
3. Reasons?
4. How to prevent infestation?
5. Geographic distribution?

Answer 5

1. Dermatobia hominis
2. Examine spiracles
3. Features:
   * Cuticular spines lacking on terminal 3 body segments (tapered on one end)
   * Spiracular plate lacking peritreme
   * Straight/slightly curved slits
4. Mosquito prevention as flies lay eggs on mosquitoes
5. Central and South America and Carribbean
6. Furuncular myiasis with non-migratory boils

Note 3 slightly curved posterior spiracles lacking a peritreme