Flashcards in Vectors Deck (114):
Name 4 common categories of vectors
mosquitos, flies, cockroaches, rodents
Most mosquitos (are/are not) harmless. Only the (female/male) is a vector of diseases.
most are not harmless
only females are vectors
Why does the female mosquito need to take in blood of warm blooded animals?
In order to mature her eggs
What attracts a mosquito to a warm blooded animal?
The carbon dioxide
A mosquito inoculates the skin with an _________________ prior to taking blood. What purpose does it serve?
It desensitizes the area prior to the bite
A mosquito bite is considered an ________________
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
The entire mosquito life cycle from egg laying to adult takes approximately _____________ days
11 to 16 days
Anopheles sp. (malaria) characteristics
adults sit at 45 degrees.
larvae don't have physical breathing tube
Culex sp. (encephalitis) characteristics
adults sit at 45 angle.
larvae have long breathing tubes
Aedes sp. (yellow/dengue fever) characteristics
larvae have short breathing tube
What tool can inspector use for a larval survey
a mosquito dipper
What is a dry ice trap
device that uses CO2 to attract mosquitos and trap them for study
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.
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
When mosquito larvae control has failed what are ways to control adult mosquitos?
using screens/bed nets
repellents such as DEET, vitamin B 12, garlic
Name 6 diseases transmitted by mosquitos
west nile virus
Name 18 diseases a fly can cause
fly larvae myiasis
African sleeping sickness
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
larvae of flies is commonly known as ___________
What are two categories of fly species
non biting variety
Name 6 types of biting flies
Non-biting flies are also known as _____________ flies
Name some common non-biting flies
domestic or synanthropic flies
green bottle fly
bronze bottle fly
lesser house fly
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
Name 4 things required for a fly to survive
What is the food source of a fly
feces, decaying organic matter, food etc. they are not picky
How does a fly eat?
it regurgitates onto the food source and then consumes it. flies require moist food.
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
What time of day are flies active? Where do they typically rest?
active during the day.
Rest on edges and protected areas from wind
the average fly can travel at ____ mph
A house fly can travel up to _____ miles in a 24 hour period
Most flies usually remain in a vicinity of about _____ square miles
1 square mile
What is the life span of a fly?
can survive 6 months of hibernation
flies are inactive below ____F and killed below ____F and above ____F
Phototropism refers to how flies are attracted to _______
house fly is scientifically known as ___________ and prefers to lay eggs in ______
Features of the cluster fly/face fly
cooler climates - attics
fly around faces of cattle
can cause pink eye
lesser house fly
smaller than house fly
sits with rear end up in the air
warm areas of the gulf coast
breeds on horse manure
False stable fly
slightly large than house fly
attracted to human foods
shiny black flies
common in cities near garbage
African sleeping sickness
red tip on abdomen
larvae used in civil war to debride wounds
bottle fly and blowfly
blowfly is green metallic
bottle fly is blue metallic
breed on dead animal flesh
black blow fly
black shiny thorax with blue/green abdomen
abundant in early spring
second in line to mosquitos for their blood sucking abilities
eggs laid on flowing water
swarm around human eyes, nose, mouth
bites become itchy
also rival mosquitos as they are vicious biters
atlantic coast and salt water/marsh lands
breed on decaying fruit
Mediterranean are very destructive
attracted to fruit liquor bottles and can end up dead inside
_______ are one of the filthiest creatures in the world
The easiest way to eliminate flies is to eliminate their ________
potential breeding environments
pick up feces and control garbage and decaying matter
If proper sanitation fails then fly larvae control can be accomplished by the following
spreading manure to dry
sugar water bowls with oil drops
What are three pesticide spraying types for flies
space sprays/aerosol bombs/space foggers - all for enclosed spaces)
aerial spraying (done by plane)
alternatives to spraying pesticides for flies include
electrocution (zaps) uv light
sterile male flies (expensive)
biological control (insects, bacteria, fungi)
What can bacillus thuringensis be used for?
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
___________________ is considered one of the most intelligent in the insect world
cockroaches belong to what family of species?
Do cockroaches bite?
Different species of cockroaches can be identified based on markings on their ________________
pronotum (body shell)
Name 4 species of cockroaches which can plague human residences and food establishments
can come from potato sacks, onion bags, cardboard
pale to light brown with two longitudinal stripes
warm moist dark environments
7-10 months lifespan
brown banded cockroach
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
What are ootheca?
eggs of cockroaches
resemble a beetle
outdoors, moist dark water areas
1-2 '' long
4-5 month lifespand
largest of domestic cockroaches
3-4 '' long
red/brown may have dark spots
common in sewers
they can fly
cockroaches are active at (day/night/both)
What is pyrethrum used for?
can be used to bring cockroaches out of hiding
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
What does cockroach odor smell like?
can smell slightly sweet and musty
Do cockroaches carry diseases?
no but they can mechanically transfer contamination since they tend to move around from dirty areas to clean areas.
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
What is the best method of cockroach extermination
tenting the premises with fumigation gas
it's expensive though and required temporary relocation of tenants
when spraying an apartment complex for cockroaches which direction should spray be applied?
from the outside to the inside
after spraying pesticides for cockroaches how long do tenants usually need to stay out of the premises?
WHy are resprayings for cockroaches required 3-4 weeks after the intial spray?
because the eggs from the prior infestation could hatch
What are the two common tenting gases used for cockroaches?
What are 4 methods that consumers can use to treat cockroach infestations
home use pest control sprays
roach motel insect traps
combat insecticide baits
How does a roach motel work?
it's a cardboard box with an odor attractant. an adhesive strip traps the roach
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
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
What is an illegal cockroach treatment
insecticide chalk from china
List 8 rodent-borne diseases
rat bite fever
describe the common victims of rat bats
sleeping children with food debris near the mouth. poor socio-economic environments
Name 3 domesticated rodents of concern to environmental health
adults 1 - 1.5 feet in length about 1 lb
thick tails shorter than body length
grayish red, brown, black
female litters of up to 8 rats as many as 7 times a year
prefer subground environments
do not like to climb
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
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
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
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
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
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
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
a dirty and oil mark left on wood beams often where rats infest
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.
which rodent burrows?
What is a concrete L used for?
under housing and buildings to prevent Norway rats from burrowing into homes
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
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.
Name the 4 routes of absorption for pesticides
stomach poisons (baits)
contact poisons (dusts)
fumigant poisons (inhaled)
dessicants (dries out the pest)
a highly toxic substance would have an LD50 of _______ mg/kg
5000 and up non toxic
LD50 of 1500
What is allethrin
a synthesized form of pyrethrum with a higher toxicity level
what is an example of pesticides with chlorinated hydrocarbons
DDT and lindane
low doses are used for head lice
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
LD50 of 60
soil poison for termites
worked well on crawling insects but studies showed it vaporized and harmed people
LD50 of 5000
flea, flies, moths
relatively non toxic
can be used around dairys
extremely toxic affects CNS
Name 6 anticoagulants used as rodenticides
how do anticoagulants work as rodenticides (bait)
intake causes internal bleeding
however some rodents are resisting bait with anticoagulants
Name 10 toxic poisons - only applied by license pest control
zinc phosphide - garlic smelling gray powder)
organophosphates and carbamates - CNS
paris green (mainly arsenic)
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
the most common cockroach found in the food establishment is ____________