Medical Entomology

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about 4000 species ,
Bare serious domestic pests
ORDER BLATT ARIA Peri
Blatta orientalis planeta americana
iknownasroacheslsteambufBlate.HU
germanica
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German cockroach -
Oriental cockroach
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American cockroach
found in cool temperate regions around the world
found inmost parts of the world occur
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worldwide distribution
- -
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10 -15mm smallest domestic cockroaches -
blackish -

35 -40mm
mechanical vectors for various bacteria protozoa
pathogenic virus
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-
,
/ ,
20 -27mm 10h9
light yellowish brown shiny reddish chocolate
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- -
,



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nocturnal -


egg case is light-coloured , 7 -9mm long , -

eggcaseislo -12mm ,
contains 16-18 eggs brown color

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omnivorous and voracious feeders contains about 40 eggs -


egg case d- 8 -10mm

foodtiytoungnymphst
,



live for 5- to weeks without water and many months without
todays ) Supetlalongipalpa containing 'be9Ys
periplanetaautraiag.ae
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disgorge partially digested meals and deposit excreta almost brown banded cockroach
on
anything
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Australian cockroach
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Temperate countries
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occurs around the world
in and subtropical
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have hemimetabolous lifecycle occurs
tropical areas
found
- -


a in warmth
places
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10 -14mmlong
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31 -37mm
warm countries
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common colour : chestnut brown , black -
darker
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yellow and brown bands
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eggcasetsa -5mm contains
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found in dark places
pale yellow stripe on each forewing
,
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site : to -50mm
long -




about 16 eggs
body consists head pronotum abdomen egg case contains 22-24 eggs
-
-
: ,
,


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wings
:
zpans ( forewing and hindwing ) >
tegmiha : thick and leathery Importance Applications
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flattened dorsoventrally with smooth , shiny and tough integument ① Nuisance
residual sprays
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covered with small and bristles
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Pests dusk
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legs
:
spines -




-

give along lasting offensive
.
smell
aerosols
have prominent segmented pilose cerci
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② Disease smokes
for
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mouthparts :
chewing gnawing scraping
, ,
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allergies
infectious agents proven / suspected carriers
of
lifecycle
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:



and should be done altera month and when cockroaches
organisms parasitic worms spraying
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① Eggs reappear
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laid encased in ootheca ( contains 12-50
eggs )
-
ootheca are partly protruding from the
tip of the abdomen Cesp - Blattaria
germanica)
management
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deposited into cracks and crevices in dark secluded places ① Environmental management
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cleanliness and hygiene
live for months to 2 or more
years
many
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reduction of accessibility
laid during the lifetime of a female
- -
effective duration depends on : -


thoroughness of application
4-90 ootheca are
speed ofreinfestatiou
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② Chemical control
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difficultto control with insecticides
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chemical used
② Nymphs resistant to used dosage and formulation applied
because :( i ) commonly
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hatch after 1-3 months ( depending and compound of insecticides type of applied surface
temp species)
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-

on .




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pale delicate version of adults Iii) many insecticides are
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temperature and humidity
repellent to them so they avoid - amount of
wearing and rubbing off occurs
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wingless
gives only temporary relief
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commonly have 5- 7-
nymphal stages that vary according to temp Insect growth regulators
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,
should be accompanied with environmental
,
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abundance of food and highly toxic Winsett larvae
species sanitation and house improvement
or
pupae
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lasts for 2-3 months ( Blattella germanica ) 12-15 months ( Blatta orientalis ) insecticides are effective for several days to months interfere their development into adults
-
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, , -




10-14 months lpeviplaneta americana) ocassionallyupto 23 months usage limited by their high cost and limited availability
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be combined with attractants as toxic baits
,
☐
-
can

, FAMILY CIMICIDAE ( BEDBUGS ) FAMILY REDUVIIDAE ( KISSING BUGS )

size 5mm ( 3mm ( width)
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bloodsucking bugs
length)
:
,
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more than 130 species in 15-17 genera
shape : oral , flattened dorsoventrally -
in
subfamily triatominae ( aka kissing bugs , come -


nosebag , vinohucasibarbeiros )
colour :
yellowish ,
dark brown , red / if recently fed ]
:( a) Tviatoma infestans
Head : short , w/ broad pair of eyes segmented antennae
, 4 Important species
(b) Tñatomadimidiata
Proboscis fold beneath head swing forward when feeding
:
,

(c) Rhodninsprolixus
2 common
species :( a) Cimexlectulavis (d) Panstrongylusmegistus
distributed in
topic and tropic countries and South America )
non
spreading Chagas disease in Central
-
-
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(b) cimex
hemiptems ( tropical bedbugs )
essential in old and New world tropics Site 5- 45mm
long mostly 20 -30mm
:
-
-
,



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can also occur in warm areas of non tropic -
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Head :
long snout -
like , pair of prominent dark coloured eyes , pair of laterally situated long and
, 4 segmented
•

antennae
proboscis thin and straight lies closely oppressed to ventral surface of head
lifecycle
-

: -

,




undergo incomplete metamorphosis is
swung forward and downward
when feeding
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immature stages resemble adults and occupy ecological niche
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Abdomen 11 segmented oral like
same :
shape
-
-
,




① Eggs First thoracic
segment consists a conspicuous triangular pronotum
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:


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glue to cracks and crevices of walls and furniture
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Meso and meta thorax : hidden dorsally by folded forewings ( hemelytron )
lifetime ( depending environmental conditions and access to blood meals )
lay 300
eggs over on
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-

Colour : brown black -

, some more colourful
elongate operculate cream to pink
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, ,



1mm
long lifecycle
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Chagas disease
-
hatch after 10 days to 1st instar nymph ① Eggs -
atoonouts

② Nymph 1.5 -2.5mm long causative agent Trypanosoma
: cruzi
-
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b-
nymphal stages oral shape slight constriction before
operculum ( cap) ( South American
trypanosomiasis )
-
-
,



each require blood meal to moult to the next smooth ornate shell 1 pearly white pink or yellowish ) efficiency of vector depends on
-


a
stage
-
, -

:



can survive 4 months w/o a blood meal lay eggs a day ( total 50-1000
1- 2
depending on
speed of feeding
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③ Adult species and no d- blood meals ) . -
whether they defecate when feeding
survive over a
year w/o feeding ② Nymph
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completion of lifecycle is 10 weeks
average ( depends on temperature humidity host
availability and habitat ) control
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, , -

hemimetabolous
with residual insecticides
spraying
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hatch after 10-15 days incubation period of 30-60 days
Importance
- /

insecticidal smoke bombs
cracks and crevices for 2-3 days before blood
.




nuisance
- hidden in
cracks and crevices around the house
.


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plastering
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feed at night sleeping people
on feeding
nymphal stages each stage require atleast
- b- ,
1 blood
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inactive during daytime and hide in dark dry places
,


meal before next stage
not considered a vector
ingest 6- 12 ✗ their weight of blood last stage about 5- Gx
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- can ,




control ③ Adults
insect only adults have wings
repellents
-
-
use
adults both feed at night for about Mimms
nymphs and 10 -




pyrethroid impregnated bed nets
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use
-
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floors and walls with pyrethrin can survive 4-6 months of starvation
spray synthetic pyrethroids
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or
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- defecate during / soon after feeding to transmit Chagas disease