Other Biting Flies Horse-flies, Tsetse-flies, House-flies and Stable-flies
Family: Tabanidae (Horse-flies and Deer-flies) • Tabanus atratus • Tabanus nigrovittatus • Chrysops atlanticus • • • • • •
Large biting flies (65 mm wing) Over 4300 species Worldwide distribution. Medium to large (6-30 mm) Antennae are small but stout Mouthparts adapted for biting, hang downwards from head.
Life History • Tend to lay eggs near larvarial substrate. • Some larvae are predacious • Life cycle – Eggs Larvae Pupae Adult – Most inhabit woods and forest
Feeding Habits • Bite is painful • Most feed during the daytime, locate host by site and CO2. • Several small meals often taken from the same or different host. • Interrupted feeding behavior increases their likelihood of being mechanical vectors of disease. • Prefer dark objects, will bite through colored clothing.
Biological Transmission • Loiasis (loa loa) • Chrysops species are the biological vectors. – Microfilaria picked up in blood during day. – Develop in thoracic fat bodies of the deer fly. – Worms leave the proboscis when deer fly feeds. • Human strain of Loiasis • Monkey strain of Loiasis
Biological Transmission • Anthrax (Bacillus anthracis) • Tularaemia – from rabbits, horses and other rodents to humans. • Tabanids can transmit viruses, bacteria, protozoa, and filarial worms to livestock • Also big pest nuisance. • Some people develop allergic reaction. • Control: Insect repellents.
Family: Glossinidae (Tsetse-flies) • Restricted to sub-Saharan Africa. • Vector: • Parasite: • Reservoir:
Life History • Egg Larvae Pupae Adult – Egg completes maturation in ovary – Larvae goes through 3 instars in the female – Larviposition in shaded areas. – Larvae bury itself in soil and pupates. – Pupal stage is long. • Adults spend day resting on vegitation or dark humid sites. (Twigs, branches, tree trunks)
Feeding Habits • Both male and females blood feed on humans, wild and domesticated animals, as well as reptiles and amphibians. • Feed in dry-hot weather, cooler weather they feed every 10 days. • Vision is important in host location. • Females must take several bloodmeals to feed larvae. • Many species rarely feed on people.
Medical Importance • •
“African Sleeping Sickness” 400,000 cases a year with 55,000 deaths.
Control Most control aimed at adults. - Clearing away vegetation (resting sites) - Kill of game animals (reservoir), no longer acceptable! - Insecticides - Targets and traps - Genetic
“The Higher Diptera” • Suborder Cyclorrhapha: – Larvae are maggots or grubs (no distinct head capsule) – Pupa is encased in final larval stage called puparium
• Families: – – – – –
Muscidae Calliphoridae Sarcophagidae Cuterebridae Oestridae
“The Higher Diptera” •
Importance: – – –
(1) Annoyance (2) Disease Transmission (3) Myiasis
(1) Annoyance • Synanthropic • Various species: – – – –
Musca domestica Fannia canicularis Musca stabulans Stomoxys calcitrans
• Several generations each year!
(2) Transmit Pathogens • Diseases transmitted mechanically. • Pathogens of bacillary dysentery: – Shigella and Salmonella
– Vomit on food when feeding
• Look at a fly close up: – Lots of hairs – Sticky pads
Family: Muscidae (House-flies and Stable-flies) • Musca domestica • Mechanical transmission of pathogens, accidental myiasis.
• Stomoxys calcitrans • biting pest (human and veterinary pest)
House Fly •
Can transmit a large number of diseases to humans.
Over 100 different pathogens have been recorded from house flies, 65 of them are transmitted!
Some diseases they can transmit: – Viruses: Polio, coxsackie, and infectious hepatitis – Rickettsiae: Q fever – Bacteria: anthrax, cholera, shigella and salmonella species, E. coli, staph. Aureus, trachoma, spirochaetes of yaws. – Protozoans: Entamoeba, Cryptosporidium, and Giardia. – Helminths: various eggs; Ascaris, tapes, Trichuris – Dermatobia hominis: a myiasis-producing fly.
Life Cycle • Egg Larvae Pupa Adult. • This life cycle is typical of other muscid and calliphorid flies. • Seasonal abundance of house flies
House Fly Control (1)
Physical and Mechanical Control -
Screening windows, openings, air vents, etc. Air barriers (doorways) Sticky tapes (fly-papers)
(2) Environmental Sanitation Reduce breeding places (garbage and refuse removal) (3) Insecticide Control Larvicides Spraying against adults Residual spraying -
Insecticidal cords Toxic baits
Stable-Flies • Both male and females take blood meals from wild and domestic animals. • Not known to transmit any diseases to humans – annoyance to animals and man. • Get rid of manure, spray breeding places with insecticides, fly strips. Biting mouthparts
Important Fly Pests of Humans and Animals in North America