Filth and Biting Flies Flashcards
flies’ physical characteristics
Order Diptera
One pair of functional wings
Pair of knobbed balancing organs called halteres
Compound eyes
2 mouthparts: sponging, piercing/sucking
Adapted for liquids and semi-solids
Saliva is released to help dissolve and collect food particles
Breaks down the solids into liquid form
sponging
used for liquids only, as seen in blood-feeders and predatory species
piercing/sucking
flies develop through which life cycle
complete metamorphosis
Flies’ egg stage:
can lay a single egg to a thousand eggs
eggs begin to hatch within hours of being laid
Flies’ larvae stage:
Non-aquatic = “maggot”
designed for only eating
do not have eyes or legs
aquatic, but require fast flowing water for larval stage
Black flies
use dry cracked soil with little moisture content
Sand flies
typically breed in rotting material
Filth flies
(housefly/bottle flies)
Fly pupae stage:
inactive and non-feeding stage
Fly adult stage:
Size, color, and behavior vary greatly depending on the species
Medical importance of Filth Flies
diseases
Diseases associated with feeding on and reproducing in garbage, feces, flesh, and vegetable matter are transferred to humans through
mechanical control
is the infestation of living human or animal tissue with fly larvae
Myiasis
result of ingesting larvae-contaminated food
Accidental Myiasis
larvae that normally feed on feces or carrion has adaptation that allow it to survive in a living host
Facultative myiasis
larvae must live on a live host for at least part of its life cycle
Obligatory myiasis
Survive only on living animal flesh
Most commonly occurs in Central and South America
Screwworms
common in parts of Mexico southward into South America. It parasitizes a very wide range of animals in addition to humans
Human Bot fly
Medical importance of Biting Flies
Vector & Diseases
Biting flies have piercing-sucking mouthparts and pathogens or pathogenic organisms are transmitted by blood feeding through
Biological transmission
vectors of Leishmaniasis cause skin ulcers in both the old and new world
Sand Flies
vectors of Onchocerciasis cause river blindness in Africa, Central and South America and are vicious biters
Black Flies
Biting flies have also been proven to be mechanical vectors of Tularemia and Anthrax from deer and horse flies
Mechanical Transmission
Direct Effects of Biting Flies
Painful bites that can cause immense itching, leading to secondary infections from scratching.
Nuisance that can lead to a decrease in morale of troops
can give a quantitative index of fly populations, but remember to be consistent in trap locations, time of day, and the bait material used
Trapping
surveillance should be based on
Populations At Risk (PAR) on base
Traps for Filth Flies
Cone trap
Traps for Biting Flies
Manitoba trap
Equipment can be placed on dumpsters or atop garbage cans
Visual count
Good for collection of species present and numbers
Sticky traps
Cultural Control:
first and most critical line of defense against flies
sanitation
Public Health should educate troops to ensure proper sanitation standards are being met
Cultural Control
Biological Control:
for maggots and pupae, however not feasible for the Air Force.
Parasitic wasps
Biological Control:
Screwworm fly was eradicated
Release of sterile males
Chemical Control:
leaves a residue to continue killing insects when contact is made
residuals
Chemical Control:
kills rapidly, but short-lived effectiveness unless treatments are repeated
baits
Chemical Control:
may be useful outdoors when flying species numbers are a nuisance
remember to protect food, and associated utensils and equipment
fogging
Mechanical Control:
screens to keep flies out of buildings. Air curtains are also useful
exclusion
Mechanical Control:
inexpensive, but effective supplementary method of fly control (i.e. cones or jars)
physical traps
Mechanical Control:
only effective in areas such as hallways.
prohibited by the food code in food prep and consumption areas
Electrically charged screens
only prevention for biting flies and myiasis
Personal Protective Measures
