houseflies and myiasis

Question 1

define syanthropic

Answer 1

live in close association with man and human settlements

Question 2

4 types of housefly

Answer 2

Musca domestica
M. sorbens
Fannia
Stomoxys ‘stable fly’

Question 3

what doe hosueflies have in common with mites

Answer 3

they dont bloodfeed

Question 4

morphological characteristics of m.domestica

Answer 4

4 dark stripes on thorax

wing vein 4 bends to meet vein 3

Question 5

how do m.domestica feed

Answer 5

suck up liquid from food sides, regurgitate and defecate on body surface

Question 6

m.domestica transmit…

Answer 6

enteric bacteria like shigella, salmonella, e.coli
cholera
helminth eggs?
polio

Question 7

what behavioural differences are there between m.domestica and m.sorbens

Answer 7

D: endophilic, feed on food waste
S: exophilic, feed on faeces

Question 8

Medical importance of m.sorbens

Answer 8

chlamydia trachomatis- trachoma

Question 9

fannia transmits…

Answer 9

no disease but eggs laid on urine soaked bedding, animals, humans which leads to urino-genital myiasis

Question 10

how can you distinguish a housefly from a stable fly

Answer 10

stable fly has prominent forward pointing piercing proboscis that penetrates skin of cattle and man to suck blood

Question 11

wha are stable flies vectors of

Answer 11

trypanosomes in cattle

Question 12

what is myiasis

Answer 12

infestation of living tissues and organs by the larva of flies

Question 13

genus names for:
tumbuflies
botflies
screwworms
blowflies
fleshflies

which are obligatory and facultative parasites

Answer 13

cordylobia    (o)
dermatobia  (o)
cochliomyia  (o)
calliphora     (f)
sarcophaga   (f)

Question 14

tumbu fly and bot fly cause cutaneous myiasis, describe the pathology

Answer 14

Tumbu fly
eggs laid on urine soaked clothes or sandy soil
larvae burrow into skin and form boil-like swellings (buttocks genitalia back)
merge from skin and pupate in soil

Botfly
eggs attached to mosquito or stomxys
larvae hatch and drop onto skin
burrow into skin forming boil-like swellings

Question 15

describe invasive myiasis

Answer 15

screwworms (cochliomyia) invade natural orifices like nose mouth eyes
sever tissue trauma
screwworms have spines and are screw like

Question 16

describe non-invasive myiasis

Answer 16

blowflies (calliphora)
will infest and consume necrotic tissue
good for healing wounds

Question 17

control of houseflies

Answer 17

refuse disposal to prevent breeding
screening premises
traps
insecticide
sterile insect technique