2-Flies and Zoonoses, Percutaneous Zoonoses Flashcards
Who are common reservoirs for myiasis?
Who are “accidental” hosts?
- Animals
- Humans
Infestation with fly larvae is known as what?
Myiasis
When blowfly larvae simply infest dead flesh or open wounds is known as what?
Fly “strike”
Are “Bot” flies and Screwworms obligatory or facultative parasites?
Obligatory
What are 3 species of “Bot” flies?
- Oestrus ovis
- Dermatobia
- Cuterebra
What are 2 types of Screwworms?
- New World
- Old World
Is Lucilia sericata an obligatory or facultative parasite?
Facultative
What is the fly life cycle?
ELPA
Oestrus ovis is known as what?
Sheep nasal bot fly
Can Oestrus ovis infest goats?
Yes
Oestrys ovis can infest the mucous membranes of humans in what 3 areas?
- Nose
- Conjunctiva
- GI
How do you treat an infestation of Oestrus ovis?
Removal of larvae (surgical).
Cuterebra is also known as what?
The rodent/rabbit botfly
What are 3 species that can be infested by Cuterebra?
- Cats
- Dogs
- Rabbits
Where are Cuterebra considered enzootic?
Parts of USA and southeast Canada
Can humans be infested with Cuterebra?
Yes
What is Dermatobia hominis known as?
The “human” botfly
Are Dermatobia hominis very species-specific?
No
What are 5 species that can be infested by Dermatobia hominis?
- Humans
- Cattle
- Dogs
- Monkeys
- Swine
How does Dermatobia hominis usually present?
As skin nodules.
Are Dermatobia hominis exotic to the USA?
Yes
How can Dermatobia hominis get into the US?
People and dogs who travel to endemic regions can bring bots back with them.
Does the USA have Screwworms?
No
T/F: Screwworm larvae are obligate parasites.
True
Where does a female screwworm fly lay her eggs?
On a wound or mucous membrane.
Do Screwworms display a mild or aggressive myiasis?
Aggressive myiasis
Which species of fly larvae feeds on living flesh?
Screwworm
What makes the wounds infested by Screwworms larger, allowing more flies to infest?
Toxins
What can Screwworm larvae live on?
What are 4 examples?
- Anything
- People, cattle, deer, dogs
When did Screwworm eradication begin in the USA?
1950s
When were Screwworms eradicated in the USA?
1966
Where does the eradication zone of Screwworms started in the USA extend to?
Extends through Central America
In 2007, Screwworm was found in a dog in Mississippi which had been imported from where?
Trinidad and Tobago
Screwworms can sometimes be found in dogs and horses imported from where?
Central and South America
T/F: Screwworms are tropical.
True
Cochliomyia hominivorax is known as what?
New World Screwworm
Chrysomya bezziana is known as what?
Old World Screwworm
Are Screwworms exotic to the USA?
Yes
Flies that are attracted to open wounds and are not obligately parasitic cause what?
Facultative Myiasis
Lucilia sericata are a very common problem in what species?
Sheep
Occasionally what species can be infested by Lucilia sericata?
Humans
Can Lucilia sericata be found in the USA?
Yes
What is an example of a nematode that can be transmitted by face flies?
Thelazia californiesis
Where are the eggs of Thelazia laid?
In the conjunctival and lacrimal sacs.
Which life stage of Thelazia is picked up by face flies?
What are 2 examples of face flies that can transmit Thelazia?
- L1
- Musca or Fannia spp.
What life stage does Thelazia develop to in the fly?
L3
Where do the Thelazia larvae migrate to in the fly?
Mouthparts of the fly.
When do the infective larvae leave the mouthparts of the fly?
When the fly feeds on another host’s eye.
Where do larvae develop to adults?
In conjunctival and lacrimal sacs.
What are 2 examples of kinetoplastic protozoa?
- Leishmania
- Trypanosoma
T/F: Kinetoplastic protozoa are facultatively parasitic, with free-living forms.
False - They are obligately parasitic, with no free-living forms.
T/F: Kinetoplastic protozoa are not good at evading immunity but can cause acute infections.
False - They are good at evading immunity and cause chronic infections.
What are 2 species of protozoa that are diverse, with both zoonotic and anthroponotic species found in the world?
- Leishmania
- Trypanosoma
Are Leishmania and Trypanosoma considered to be tropical?
What are 2 exceptions?
- Yes
- Leishmania infantum and Trypanosoma cruzi
How is Leishmania transmitted?
By sandflies
Where is Phlebotomus seen?
In the Old World
Where is Lutzomyia seen?
In the New World
Where in the US can Leishmania be seen endemically with vertical transmission?
US foxhound kennels
Myiasis is an invasion of what type of tissue?
Living
What type of reservoirs does Leishmania have?
What are 4 examples?
- Vertebrate reservoirs
- Hyraxes, canids, rodents, humans
Leishmania currently affects approximately how many people in who many countries?
Approximately 12 million people in 88 countries
T/F: Different species of Leishmania will cause different diseases.
True