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Flashcards in Vectors Deck (114):
1

Name 4 common categories of vectors

mosquitos, flies, cockroaches, rodents

2

Most mosquitos (are/are not) harmless. Only the (female/male) is a vector of diseases.

most are not harmless

only females are vectors

3

Why does the female mosquito need to take in blood of warm blooded animals?

In order to mature her eggs

4

What attracts a mosquito to a warm blooded animal?

The carbon dioxide

5

A mosquito inoculates the skin with an _________________ prior to taking blood. What purpose does it serve?

anticoagulant chemical

It desensitizes the area prior to the bite

6

A mosquito bite is considered an ________________

inoculation

7

List the names and times of the 4 stages of a mosquito life cycle

1. egg laying (typically on stagnant water)
2. larval stage 2-3 days eggs hatch, larvae are in water and come up to breath
3. Pupa stage 4-10 days still in water, not as active
4. Adult stage 48 hours then they sit on the water to let wings dry for 6 hours

8

The entire mosquito life cycle from egg laying to adult takes approximately _____________ days

11 to 16 days

9

Anopheles sp. (malaria) characteristics

adults sit at 45 degrees.
larvae don't have physical breathing tube

10

Culex sp. (encephalitis) characteristics

adults sit at 45 angle.

larvae have long breathing tubes

11

Aedes sp. (yellow/dengue fever) characteristics

larvae have short breathing tube

12

What tool can inspector use for a larval survey

a mosquito dipper

13

What is a dry ice trap

device that uses CO2 to attract mosquitos and trap them for study

14

What is the purpose of using petroleum based oils (Tossits) on surfaces of ponds and lakes

it blocks mosquito larvae breathing tubes causing them to drown.

petroleum can't be used in California so now some detergents are used instead.

15

Name two natural enemies of mosquitos that can be used to biologically control mosquitos. describe how they control mosquitos

Gambusia affinis (mosquito fish) a minnow species that can consume up to 200 larvae a day.

dragon fly - dragon fly larvae eat mosquito larvae, and adult dragon flies eat adult mosquitos

16

When mosquito larvae control has failed what are ways to control adult mosquitos?

spraying insecticides
using screens/bed nets
protective clothing
repellents such as DEET, vitamin B 12, garlic

17

Name 6 diseases transmitted by mosquitos

west nile virus
malaria
yellow fever
dengue fever
encephalitis
filariasis

18

Name 18 diseases a fly can cause

onchoceriasis
bacillary dysentery
hepatitis
round worms
tapeworm
ameobiasis (cycsts)
typhoid fever
amoebic dysentery
fly larvae myiasis
whipworm
shigella
African sleeping sickness
paratyphoid fever
infantile diarrhea
pinworms
hookworm
salmonella
e-coli

19

describe the body characteristics of a fly

lower abdomen, thorax with single pair of wings, head with large compound eyes, mouth and antennae. three pairs of legs

20

larvae of flies is commonly known as ___________

maggots

21

What are two categories of fly species

biting variety
non biting variety

22

Name 6 types of biting flies

horse fly
deer fly
stable
flesh fly
black fly
sand fly

23

Non-biting flies are also known as _____________ flies

Name some common non-biting flies

domestic or synanthropic flies

house fly
green bottle fly
bronze bottle fly
cluster fly
blow fly
screwworm fly
filter fly
moth fly
lesser house fly

24

Describe the 4 stages of the fly life cycle

1. eggs - sometimes carried with the adult until ready to hatch. need moisture, warmth and nutrients

2. larvae - aka maggots, active white worms

3. pupa - not mobile, matures in soil

4. adult fly

25

Name 4 things required for a fly to survive

Warm temperature
Moisture
Food Source
Soil

26

What is the food source of a fly

feces, decaying organic matter, food etc. they are not picky

27

How does a fly eat?

it regurgitates onto the food source and then consumes it. flies require moist food.

28

How can a fly cross contaminate?

e.g. would be feeding on dog feces then landing on your food and regurgitating diseases picked up from the dog feces

29

What time of day are flies active? Where do they typically rest?

active during the day.

Rest on edges and protected areas from wind

30

the average fly can travel at ____ mph

4 mph

31

A house fly can travel up to _____ miles in a 24 hour period

6 miles

32

Most flies usually remain in a vicinity of about _____ square miles

1 square mile

33

What is the life span of a fly?

ranges greatly.

2-4 weeks

can survive 6 months of hibernation

34

flies are inactive below ____F and killed below ____F and above ____F

45
32
112F

35

Phototropism refers to how flies are attracted to _______

light

36

house fly is scientifically known as ___________ and prefers to lay eggs in ______

musca domestica
feces

37

Features of the cluster fly/face fly

musca autumalis
cooler climates - attics
fly around faces of cattle
can cause pink eye

38

lesser house fly

fannia cunicularis
smaller than house fly
rarely lands

39

Stable Fly

Stomoxys calcitrans
sits with rear end up in the air
warm areas of the gulf coast
vicious biters
breeds on horse manure

40

False stable fly

muscina stabulans
slightly large than house fly
attracted to human foods

41

Dump Fly

shiny black flies
common in cities near garbage

42

Tse-tse fly

tropical, Africa
brown colored
African sleeping sickness

43

Flesh Fly

sarcophagi occidua
red tip on abdomen
larvae used in civil war to debride wounds

44

bottle fly and blowfly

blowfly is green metallic
bottle fly is blue metallic

breed on dead animal flesh

45

black blow fly

black shiny thorax with blue/green abdomen

abundant in early spring

46

Black Fly

second in line to mosquitos for their blood sucking abilities
eggs laid on flowing water
swarm around human eyes, nose, mouth
bites become itchy

47

Deer Fly

chrysops discalis
also rival mosquitos as they are vicious biters
atlantic coast and salt water/marsh lands

48

Fruit Fly

drosphillidae
breed on decaying fruit
Mediterranean are very destructive
attracted to fruit liquor bottles and can end up dead inside

49

_______ are one of the filthiest creatures in the world

flies

50

The easiest way to eliminate flies is to eliminate their ________

potential breeding environments

pick up feces and control garbage and decaying matter

51

If proper sanitation fails then fly larvae control can be accomplished by the following

spreading manure to dry
using pesticides
traps
sugar water bowls with oil drops

52

What are three pesticide spraying types for flies

residual sprays
space sprays/aerosol bombs/space foggers - all for enclosed spaces)
aerial spraying (done by plane)

53

alternatives to spraying pesticides for flies include

fly baits
fly cords
resin strips
screening
air curtains
electrocution (zaps) uv light
sterile male flies (expensive)
biological control (insects, bacteria, fungi)

54

What can bacillus thuringensis be used for?

fly control

55

What are three devices use to trap flies for surveying

baited fly trap - set on ground, cheap method

fly cones - similar to fly trap

fly grill - most commonly used - gives faster assessment of population. the grill is placed over natural attractants

56

___________________ is considered one of the most intelligent in the insect world

the cockroach

57

cockroaches belong to what family of species?

Blattidae

58

Do cockroaches bite?

no

59

Different species of cockroaches can be identified based on markings on their ________________

pronotum (body shell)

60

Name 4 species of cockroaches which can plague human residences and food establishments

german
brown banded
oriental
american

61

german cockroach

blatella germanica
can come from potato sacks, onion bags, cardboard
most common
1/2-3/4 inch
pale to light brown with two longitudinal stripes
warm moist dark environments
7-10 months lifespan

62

brown banded cockroach

supella longipalpa
1/2 '' long
light brown color w/ one dark band

aka radio or TV roach
like warm dry environments
males can fly
3-7 months lifespan

63

What are ootheca?

eggs of cockroaches

64

oriental cockroach

blatta orientalis
resemble a beetle
outdoors, moist dark water areas
cannot climb
shiny black
1-2 '' long
4-5 month lifespand

65

American cockroach

periplaneta Americana
largest of domestic cockroaches
3-4 '' long
red/brown may have dark spots
common in sewers
they can fly

66

cockroaches are active at (day/night/both)

night time

67

What is pyrethrum used for?

can be used to bring cockroaches out of hiding

68

What does cockroach defecation look like and where can it be found?

small brown specks like ground pepper.

can stain walls
often in cabin doors and other crevices

69

What does cockroach odor smell like?

can smell slightly sweet and musty

70

Do cockroaches carry diseases?

no but they can mechanically transfer contamination since they tend to move around from dirty areas to clean areas.

71

which cockroach species are more likely to cause an infestation inside?

german and brown banded

unless there is a plumbing leak then maybe the American or oriental

72

What is the best method of cockroach extermination

tenting the premises with fumigation gas

it's expensive though and required temporary relocation of tenants

73

when spraying an apartment complex for cockroaches which direction should spray be applied?

from the outside to the inside

74

after spraying pesticides for cockroaches how long do tenants usually need to stay out of the premises?

4-6 hours

75

WHy are resprayings for cockroaches required 3-4 weeks after the intial spray?

because the eggs from the prior infestation could hatch

76

What are the two common tenting gases used for cockroaches?

methylbromide
vikane

77

What are 4 methods that consumers can use to treat cockroach infestations

home use pest control sprays
roach motel insect traps
combat insecticide baits
glue traps

78

How does a roach motel work?

it's a cardboard box with an odor attractant. an adhesive strip traps the roach

79

How do combat insecticide baits work for cockroaches

black disposable plastic slotted with odor attractant and poisonous bait the cockroach does not die immediately so where you find dead roaches will be where the infestation is

80

How can boric acid powder be used against cockroaches

they will groom themselves and then be poisoned.

the powder can be applied to crevices and other areas

81

What is an illegal cockroach treatment

insecticide chalk from china

82

List 8 rodent-borne diseases

rat bite fever
murine typhus
leptospirosis
plague
salmonellosis
rickettsial pox
trichinosis
lymphocytic choriomeningitis

83

describe the common victims of rat bats

sleeping children with food debris near the mouth. poor socio-economic environments

84

Name 3 domesticated rodents of concern to environmental health

Norway rat
roof rat
house mouse

85

Norway rat

rattus norvegicus
adults 1 - 1.5 feet in length about 1 lb
thick tails shorter than body length
stocky body
grayish red, brown, black
small eyes
female litters of up to 8 rats as many as 7 times a year
"sewer rat"
prefer subground environments
do not like to climb
vicious

86

roof rat

rattus rattus
aka "laboratory rat"
smaller and less vicious
slender body and tail is 1/3 longer than body
1.5 ft lgnth
fur varies, brown, gray, black (light on underside)
large eyes and ears
litters of 6-8 up to 6 times a year
very good climber
lives in warmer climates, sourthern US and subtropical
live in higher elevations
pickier eaters

87

house mouse

mus musculas
smallest
2.5 to 3.5 inches long
tails are 2-4 inches longer than body
weight under an oz
gray brown fur
pointy nose and large eyes
under houses, between walls, cabbinets
can survive dry environments they like cereal grains

88

describe the senses and physical abilities of rodens

eyes - poor sight, color blind
excellent hearing, sense of smell and taste
great balance and agility, can jump up to 2 feet
great swimmers
they run along walls because their hairs have a strong sense of touch
they are weary of strange things which prevent traps from working sometimes

89

rodent dropping identification

Norway rat - large up to .75 inches long shaped like a capsule

roof rat - .5'' droppings with banana shaped ends

house mouse - .25'' droppings are very small and pointy rod shaped

90

How can you tell fresh rodent droppings from old ones

fresh will be soft, moist, dark and shiny

grey or crumbly can be a few days or many weeks old

91

how is tracking powder used in rodent identification

can be laid along walls and looked at by flash light to see if an infestation is present

92

rubmarks

a dirty and oil mark left on wood beams often where rats infest

93

Why do rodents gnaw?

because their front incisors grow 4-6 inches a year so they have to grind them down

results in wood being destroyed
electrical wires etc.

94

which rodent burrows?

Norway rat

95

What is a concrete L used for?

under housing and buildings to prevent Norway rats from burrowing into homes

96

how can a home be rodent proofed?

vents should be screened
pipes should be no greater than 1/4 ''
bushes and trees should be cut back from building
make sure doors are flush

97

What is the purpose behind ectoparasite control in rodents?

because rodents are an excellent vector to other organisms such as fleas.

powdered pesticides such as sevin, malathion and diazinon should be used.

98

Name the 4 routes of absorption for pesticides

stomach poisons (baits)
contact poisons (dusts)
fumigant poisons (inhaled)
dessicants (dries out the pest)

99

a highly toxic substance would have an LD50 of _______ mg/kg
toxic
moderately toxic
slightly toxic
non toxic

5-50 highly
50-500
500-1000
1000-5000
5000 and up non toxic

100

pyrethrum

botanical
LD50 of 1500
chrysanthemums

101

What is allethrin

a synthesized form of pyrethrum with a higher toxicity level

102

what is an example of pesticides with chlorinated hydrocarbons

DDT and lindane

103

lindane

low doses are used for head lice

104

ddt

dichlorodiphenyltrichloroethane
BANNED!
LD50 of 500
very effective pesticide but remains stable for too long
bad for birds and other species in the environment because DDT does not break down

105

Aldrin

LD50 of 60
soil poison for termites

106

Chlordane

worked well on crawling insects but studies showed it vaporized and harmed people

107

Methoxychlor

LD50 of 5000
flea, flies, moths
relatively non toxic
can be used around dairys

108

organophosphaste -carbamates

extremely toxic affects CNS

109

Name 6 anticoagulants used as rodenticides

prival
warfarin
fumarin
diphacinone
chlorophacinone
PMP

110

how do anticoagulants work as rodenticides (bait)

intake causes internal bleeding
however some rodents are resisting bait with anticoagulants

111

Name 10 toxic poisons - only applied by license pest control

red squill
1080
1081
ANTU
nor-bromide
strychnine
zinc phosphide - garlic smelling gray powder)
vacor
organophosphates and carbamates - CNS
paris green (mainly arsenic)

112

What are vermin

noxious or objectionable insects or animals that pose a human health risk, damage or contaminate food or property or create annoyance. common e.g. include flies, cockroaches, rats and mice

113

the most common cockroach found in the food establishment is ____________

german cockroach

114

rats typically stay within ______ ft from their nests while mice stay within ______ ft from theirs

rats 150 ft
mice 30 ft