Entomology - Ch. 7: Tsetse-flies, Filth flies. Myiasis, Coachroaches

What is Class for Tsetse flies?

Insecta

What is the Order for Tsetse flies?

Diptera

Tse-tse is the vector for…

African trypanosomiasis

What are the 4 distinct morphologies for Tsetse?

• Large

• Forward projecting proboscis

• Hatchet cell

• Blood meals for both sexes

Where is the ‘hatchet cell’ located?

middle of the wing

Tse-tseHow are the wings presented on the body?

wings

are folded over each other

What is the Tsetse plumose antennae (feather-like) called?

Arista

What is the unique feature of the reproduction of the Tsetse?

Lays one larva at a time

What is unique gland that a female Tsetse have referred to as and what does it provide?

Milk glands and it provides nutrients to larva

What are the black extensions on the ends of the pupa called?

Polyneustic lobes

What is the role of Polyneustic lobes?

breathing

Tsetse flies-Immature: What are the larval stages referred to as?

Three larval instars

Tsetse flies-Immature: Where does the female Tsetse lay the larval after it reaches the 3rd instar larva stage?

In loose soil where it can burrow down into the soil

Tsetse flies-Immature: What are the color changes that occur from larval to pupa stage?

White to dark

What are the characteristics of the pupa?

dark and hard

Tsetse flies-Medical Importance: How is the global distribution?

Mainly in Africa

Tsetse flies-Medical Importance: When does transmission occur?

At low level transmission with occasional epidemics

Tsetse flies-Medical Importance: What are the two main strains called from the Tsetse flies transmission of African Trypanosomiasis (sleeping sickness)?

• Gambia

• Rhodesian

Tsetse flies-Medical Importance: Acute or chronic sleeping sickness for Trypanosomiasis brucei rhodesiense?

Acute sleeping sickness

Tsetse flies-Medical Importance: Acute or chronic sleeping sickness for Trypanosomiasis brucei gambiense?

Chronic sleeping sickness

Tsetse flies-Medical Importance: What does the Trypanosomiasis brucei rhodesiense effect?

• Wild and domestic animals

• humans

Tsetse flies-Medical Importance: What does the Trypanosomiasis brucei rhodesiense effect?

• Domestic pigs

• humans

TB gambiense correlates with…

• Chronic sleeping sickness

• Effects domestic pigs and humans

Tsetse flies-Medical Importance: Is the parasitemia high or low in the Rhodesiense?

high

TB rhodesiense correlates with…

• Acute sleeping sickness

• Effects wild/domestic animals and humans

Trypanosomiasis cruzi is a vector for what disease?

Chagas disease

What does T. cruzi effect?

• humans

• armadillos

• opossums

• dogs

• guinea pigs

What does Trypanosomiasis rangeli transmit?

Nothing; non-pathogenic

What does T. rangeli effect?

• wild animals

• humans

Gambian sleeping sickness: Where is the disease strain primarily found in?

West and Central Africa

Gambian sleeping sickness: What type of transmission occur from areas for gathering water?

human-fly contact

Gambian sleeping sickness: What are the reservoirs for this strain?

• domestic pigs

• humans

Rhodesian Sleeping Sickness: Where is the disease strain primarily found in?

East Africa

Rhodesian Sleeping Sickness: What type of transmission occurs?

Animals-fly contact (less dependent on moisture)

Rhodesian Sleeping Sickness: Is this strain less or more widespread then the Gambian form?

Less widespread only in zoonotic areas

Rhodesian Sleeping Sickness: What are the resevoirs?

• game animals, domestic cattle

Sleeping Sickness Symptoms: What happens to the area with the infected bite & IP?

• localized rxn with a chancre (a painless boil)

• parasite continues dividing

• 5-20 days

Sleeping Sickness Symptoms: What is involved in the first phase?

• headaches

• fever (rash)

• gland enlargement from parasite divisions in blood

Sleeping Sickness Symptoms: What is involved in the second phase?

• Sleeping sickness begins

• causing tremors, speech impairment, drowsiness

• Parasite in CSF

Sleeping Sickness Symptoms: What happens in the Natural History (death) for the Gambian form?

• coma

• starvation

• occurs in 2-3 yr span

Sleeping Sickness Symptoms: What happens in the Natural History (death) for the Rhodesian form?

• shock

• 3-9 month span

Tsetse flies- Important species: What are the two species of Tsetse flies?

• Glossina morsitans

• Glossina palpalis

Tsetse flies- Important species: What are the Glossina morsitans known as and where do they reside?

• Savannah flies

• Savannah areas with low human population

Glossina morsitans =

dry area

Tsetse flies- Important species: What are the Glossina palpalis known as and where do they reside?

• riverine/forest

• shores and banks of rivers and lakes

Glossina palpalis =

river areas

Tsetse flies- Adult behavior: Where do the adult flies get their blood meal from?

• domestic/ wild mammals, reptiles, birds

• host preference

Tsetse flies- Adult behavior: What time of day do they feed & what are they attracted to?

• day time

• dark moving objects (sight and olfaction important)

Tsetse flies- Adult behavior: Where do flies rest at most of the time?

• shaded areas and on surfaces of leaves

• species specific

Control of African Sleeping Sickness: What are 5 control measures of African Trypanosomiasis?

• destroy vectors

• clearing vegetation around living areas

• Insecticide spraying along paths

• use of non-residual space sprays

• Give synthetic pyrethroid to domestic animals for treatment

Traps and Targets: What is the goal of control besides reducing the population of Tsetse?

having a method without causing environmental danger

Traps and Targets: What do traps usually not have in them?

insecticide

Traps and Targets: What may draw the flies to the traps?

• odor-baited

• such as acetone, octenol, phenols, & cow urine

• depending on Glossina species

Traps and Targets: Targets with insecticide dark (blue or black) synthetic cloth are treated with what?

Pyrethroid

Traps and Targets: What are the name of the 4 traps used to catch Tsetse?

• Bicone trap

• Screen traps

• Cloth cone traps (treated with deltamethrin)

• Target traps

Traps and Targets: What trap is this called?

Bicone trap

Traps and Targets: What trap is this called?

Sreen traps

Traps and Targets: What trap is this called and what is it treated with?

Cloth cone trap and treated with deltamethrin

Traps and Targets: What trap is this called?

Target traps

Which fly is a Tsetse fly?

A

Treatment: What was the first all-oral treatment for sleeping sickness for the Gambian strain?

Fexinidazole

Treament: What is the most recent drug of use available to cure both stages with a single dose?

Acoziborole

Treatment: What is innovative about the new drug Acoziborole?

• cures both stages with a single dose

• demonstrates efficiency in a pivotal phase 2/3 trial

• safety profile better than fexinidazole

Filth Flies & Myiasis: Out of these two and cockroaches, what species have Mechanical Transmission?

• filth flies

• cockroaches

Filth Flies & Myiasis: What is Myiasis?

Infestation with fly larvae

Mechanical Transmission of Pathogens: What is the definition of Mechanical transmission?

• Transfer of pathogens from an infected host or a contaminated substrate to a susceptible host

Mechanical Transmission of Pathogens: Is biological association necessary for the pathogen and vector?

not necessary

Mechanical Transmission of Pathogens: What can the vector be?

• arthropod

• bird

• rat

• mouse

• animal

• human

Mechanical Transmission of Pathogens: 4 General characteristics of mechanical infection of a pathogen

• no development or multiplication of vector

• multiple routes of infection (blood or water borne)

• food & water contamination

• Multiplication of pathogen in original host and in the environment (not host-specific)

Important parameters - Mechanical Transmission: what are 9 parameters for mechanical transmission?

1. Setae present on arthropod

2. Feeding behavior (pool or vessel feeding)

3. Regurgitation

4. associated with human food/ dwellings preparation areas

5. Defecation patterns

6. Stability of pathogen in environment

7. Infectioness of the pathogen

8. Number and tpyr of arthropods

9. Host immunity (associated with Bioterrorism agents)

Myiasis: How does Myiasis work?

• fly larve infesting the organs/tissues of humans or animals

• feed on dead or living tissues

• or feed on ingested food of the host

Myiasis: What is ‘accidental myiasis’ called and where does it include?

• Facultative Myiasis

• includes enteric, recto/urogenital and cutaneous

Myasis: What are the Facultative myiasis (accidental myiasis) important in?

Forensic Entomology

Myiasis: What is Obligatory Myiasis?

When the infestation is a necessary part of the fly life cycle

Facultative Myiasis 1: What does the term ‘ Enteric Myiasis’ mean?

accidental ingestion

Facultative Myiasis 1: Number of species reported and the two main species name?

• 50 species

• Muscidae

• Sarcophagidae

Facultative Myiasis 1: what does it mean if there is there passive transport of larvae?

there is no development in the host digestive tract

Facultative Myiasis 1: What are 3 bases severity is based on?

• fly specie

• number

• location

Facultative Myiasis 1: What are the 3 Genera commonly involved?

• Musca

• Fannia

• Muscina

Facultative Myiasis 2: Rectal/ Urogenital Myiasis: What does the larvae do when they have access to the intestine through the Anus?

feed on excrement

Facultative Myiasis 2:Rectal/ Urogenital Myiasis: Where can the immature stages be completed at?

rectum or terminal part of intestine

Facultative Myiasis 2:Rectal/ Urogenital Myiasis: How can this transmission take place?

Unsanitary conditions

Facultative Myiasis 2:Rectal/ Urogenital Myiasis: What are the 3 primary genera?

• Fannia

• Musca

• Sarcophaga

Facultative Myiasis 3: Cutaneous myiasis: Where does this accidental infection usually occur around?

around wounds

Facultative Myiasis 3: Where can the larvae be found at ?

meat or carrion

Facultative Myiasis 3- Cutanneoud myiasis:What are the health complications to the body?

No health tissues being invaded

Facultative Myiasis 3: Cutaneous : What are the typical species involved?

• blow fish (bottle flies) —> Calliphora

• Sarcophaga

Obligatory Myiasis: What is Obligatory Myiasis?

a parasitic condition that caused by fly larvae that require a living host to complete their life cycle

Obligatory Myiasis: Calliphorids (non-metallic): What are Cordylobia anthropophaga and what do they do?

• tumbu or mango fly (Africa)

• larvae attach and burrow into skin leaving spiracle exposed, appear as boils

Obligatory Myiasis: What is Auchmeromyia sengalensis and what is the difference in this compared to Cordylobua anthropophaga?

• Congo floor-maggot (Africa)

• Larvae does not remain attached

• feed on people at night sleeping on the floor

Obligatory Myiasis: What is the a similar thing about the Cordylobia anthropophaga and the Auchmeromyia senegalensis?

adult stage look the same

Obligatory Myiasis: What are the two Calliphorids (metallic) species called?

• Cochliomyia hominivorax (new world screw worm)

• Chrysomya bezziana (old world screw-worm)

Obligatory Myiasis: Is Chochliomyia hominivorax from the old or new world?

New World

Obligatory Myiasis: Is Chrysomya bezziana from the old or new world?

Old world

Obligatory Myiasis: What is the specie called in the Sarcophagids (flesh flies)?

Wohlfahrtia magnifica - ear, eye, nose

Obligatory Myiasis: What is the specie name in the Oestrids (bot flies) catergory?

• Gasterophilus

• Hypoderma

• Dermatobia hominis (human bot fly)

Obligatory Myiasis: What does SIT mean?

Sterile insect technology

Obligatory Myiasis: What was the goal of Sterile Insect technology in the United States?

to control the primary Screwworm fly in the Southern US

Obligatory Myiasis: How did controlling the primary Screwworm become effective in the SW US in 1966?

used X-rays to sterilize

Obligatory Myiasis: What are the three unintended consequences in using the Sterile Insect technology?

• increase in white-tailed deer population

• increase in feral hog population

• Reduced the amount of labor needed on ranches