Exam 1 Flashcards
(115 cards)
1
Q
Describe the concept of animal associations
A
Parasitism deals with animal association. How species interact with each other.
2
Q
What is parasitism?
A
A symbiotic relationship between two organisms: A parasite usually the smaller of the two, and a host, upon which the parasite is physiologically dependent. This relationship may be permanent. Example: When ticks and mosquitos feed on the host blood.
3
Q
Describe the concept of symbiosis
A
- Close association of organisms of different species.
- An organism that spends a portion or all of its life intimately associated with another living organism of a different species without any benefit or damage
4
Q
What did Eugene Odum study?
A
Affects on population growth
5
Q
What is commensalism? +/-
A
- One partner benefits and the other has no effect
Does not involve dependency between the two partners: the host and the commensal. Spatial proximity allows the commensal to feed on substances captured. The 2 partners can survive independently. For example: The association of hermit crabs and the sea anemones they carry on their borrowed shells.
6
Q
What is phoresis?
A
- 2 symbionts brawl together
- The human botfly lays their eggs on the mosquito and eggs hatch when the mosquito has a blood meal. Then the mosquito gets no effect and the botfly benefits.
The smaller organism is mechanically carried by the other larger organism which is the host. Unlike commensalism, there is no dependency in the procurement of food by either partner. Example: The numerous fungi, algae, and protozoans that attach to the bodies of aquatic anthropoids like turtles.
7
Q
What is mutualism?
A
- Obligatory physiological independence
- Termites ingest wood and digest into intestinal protists. One would die without the other
- An association in which the mutualist and the host depend on each other physiologically. Example: Protozoans and termites and whose gut they live. They need each other to survive.
8
Q
Name 4 types of attackers for exploitation relationships
A
- Predator
- Parasitoid
- Micropredator
- Parasite
9
Q
What is a predator?
A
An animal that naturally preys on others
10
Q
What is a parasitoid?
A
An insect (e.g., the ichneumon wasp) whose larvae live as parasites that eventually kill their hosts (typically other insects).Like a parasite, a parasitoid infects just one host per life stage. But parasitoids always kill their hosts. Only one organism is attacked and killed. - A female wasp deports eggs on another insect and when they hatch, they kill the host
11
Q
What is a micropredator?
A
An organism,e.g., the mosquito, that derives elements essential for its existence from other species of organisms, larger than itself, without causing their destruction.
12
Q
What is a parasite?
A
- Lives in or on a host
- Has greater reproductive potential than its host
- Gets nutrients from its host
- Has the potential of harming the host
13
Q
Generally, what is parasitism?
A
An organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host’s expense .
14
Q
What organisms are parasites?
A
A few examples of parasites are tapeworms, fleas, and barnacles. Tapeworms are segmented flatworms that attach themselves to the insides of the intestines of animals such as cows, pigs, and humans. They get food by eating the host’s partly digested food, depriving the host of nutrients.
15
Q
What are the 3 types of parasites?
A
- Helminths- A parasitic worm; a fluke, tapeworm, or nematode.
- Protozoa- Single-celled organisms with animal-like behaviors, such as motility and predation.
- Arthropods- an invertebrate animal of the large phylum Arthropoda, such as an insect, spider, or crustacean.
16
Q
What are NOT parasites?
A
- bacteria
- viruses
- fungi
17
Q
Name the 4 types a parasites
A
- Ectoparasite- On host’s surface outside such as ticks
- Endoparasite- lives inside a host
- Obligate- Must be parasite for at least part of its life cycle
- Facultative- Does not normally have parasitic opportunity. Is an organism that may resort to parasitic activity, but does not absolutely rely on any host for completion of its life cycle
18
Q
Name 2 types of hosts
A
- Definitive host (DH)- An organism that supports the adult or sexually reproductive form of a parasite
- Intermediate host (IH)- An organism that supports the immature or non reproductive forms of a parasite. Absolutely required for parasite development and does not reach sexual maturity
19
Q
What does over-dispersion mean?
A
Negative binomial. Too many parasites inside the host.
20
Q
What are the 2 types of life cycles a parasite can take into its host?
A
- Direct- Parasite passed from one definitive host to the next definitive host through air OR by a famite with food and water
- Indirect- Goes through an intermediate host
21
Q
For each of the following, identify whether it could be a parasite according to the traditional definition.
cestode-
trematode-
bacteria-
nematode-
virus-
fungus-
protozoan-
arthropod-
A
cestode- YES
trematode- YES
bacteria- NO
nematode- YES
virus- NO
fungus- NO
protozoan- YES
arthropod- YES
22
Q
Reading Question: Explain the differences between the 4 categories of symbiotic relationships.
A
- Commensalism- Does not involve dependency between the two partners: the host and the commensal. Spatial proximity allows the commensal to feed on substances captured. The 2 partners can survive independently. For example: The association of hermit crabs and the sea anemones they carry on their borrowed shells.
- Phoresis- The smaller organism is mechanically carried by the other larger organism which is the host. Unlike commensalism, there is no dependency in the procurement of food by either partner. Example: The numerous fungi, algae, and protozoans that attach to the bodies of aquatic anthropoids like turtles.
- Parasitism- A symbiotic relationship between two organisms: A parasite usually the smaller of the two, and a host, upon which the parasite is physiologically dependent. This relationship may be permanent. Example: When tick and mosquito feed on the host blood.
- Mutualism- An association in which the mutualist and the host depend on each other physiologically. Example: Protozoans and termites and whose gut they live. They need each other to survive.
23
Q
Reading Question: What is a zoonosis?
A
- A disease of humans that is caused by a pathogenic parasite normally found in wild and domestic vertebrate animals
24
Q
Reading Question: Describe the symbiotic relationship which occurs between termites and the flagellated protozoans which inhabit their gut
A
The flagellate depends on a carbohydrate diet and acquires nutrients from wood ingested by the termite. In return, the flagellate synthesizes and secretes cellulose so which the termite utilizes. They would die without each other and have a mutualist if relationship.
25
```
Sample Question
Which of the following is always physiologically dependent on the relationship with its symbiotic partner?
A. phoront
B. commensal
C. host
D. symbiont
E. parasite
```
E. parasite
26
Sample Question
Most parasite populations are overdispersed in their host population. This means that
A. most hosts who are infected produce fewer offspring than uninfected individuals
B. most hosts harbor few parasites, while a few hosts are infected with many
parasites
C. all of the hosts harbor approximately the same number of parasites
D. most hosts are infected with many parasites, while a few hosts harbor only a
small number of parasites
E. there is no relationship between hosts and the number of parasites they harbor
B. most hosts harbor few parasites, while a few hosts are infected with many
parasites
27
What are the leading causes of death in US?
The leading cause of death in the U.S. from the CDC is heart disease, cancer, stroke, lower respiratory disease, accidents, and diabetes
28
What are the leading causes of death in underdeveloped countries?
Heart disease, lower respiratory infections, HIV, diarrheal diseases with bacteria and parasites, malaria, TB
29
What are the United Nations?
2000 people called a plan for sustainable development and eradication of poverty in underdeveloped countries and call the millennium development goals. The due date for these goals was 2015
30
Name as many Millennium Development Goals (MDGs) as you can
1. Radicate extreme poverty and hunger
2. Achieve universal primary education
3. Promote gender equality
4. Reduce child mortality
5. Improve maternal health
6. To combat HIV/Malaria and other diseases
7. Ensure environmental sustainability
8. Development of global partnership
31
What was the “Big Three?”
1. HIV medications
2. Tuberculosis antibiotics
3. Malaria drugs
32
What are NTD's?
Neglected Tropical Diseases (NTDs)- A group of 17 diseases
33
Name four helminths
1. Foodborne trematodiases
2. Schistosomiasis- Caused by the parasitic fluke
3. Cysticercosis/Taeniasis- Food worm infection
4. Echinococcosis- Parasitic disease of tapeworms
5. Soil-transmitted helminths (STH)- Caused specifically by those helminths which are transmitted through soil contaminated with fecal matter
34
Name some examples of foodborne trematodiases cause by helminths
1. Clonorchiasis- Is an infectious disease caused by the Chinese liver fluke, Clonorchis sinensis
2. Fascioliasis- Infestation of a human or an animal with the liver fluke
3. Opisthorchiasis- Infection of the biliary tract by the liver flukes
4. Paragonimiasis- Infestation with or disease caused by a lung fluke
35
What are examples of soil-transmitted helminths (STH)?
1. Ascariasis- 4.2 billion people are at risk. Infection in the intestine.
2. Hookworm Infections- A parasitic nematode worm that inhabits the intestines of humans and other animals. It has hooklike mouthparts with which it attaches itself to the wall of the gut, puncturing the blood vessels and feeding on the blood.
3. Trichiuriasis- 60 million people are at risk. A disease caused from infected meat, especially pork, characterized by digestive disturbance, fever, and muscular rigidity.
36
What is Lymphatic Filariasis?
A helminth. Parasitic disease caused by microscopic, thread-like worms. The adult worms only live in the human lymph system
37
What is Onchocerciasis (river blindness)?
A helminth. 90 million people at risk. Disease caused by filarial worms. Causes impaired vision.
38
What is Dracunculiasis (guinea-worm disease)?
A helminth. Is an infection by the guinea worm. A person becomes infected when they drink water that contains water fleas
39
What are NTD's caused by?
1. Helminths
2. Protozoans
3. Bacteria
4. Viruses
40
What NTD's do protozoans cause?
1. Human African trypanosomiasis (sleeping sickness)- 60 million people infected. A parasitic disease transmitted by the bite of the 'Glossina' insect.
2. Chagas disease- A disease caused by trypanosomes transmitted by bloodsucking bugs. Affects the heart and nervous system.
3. Leishmaniases- A tropical and subtropical disease caused by leishmania and transmitted by the bite of sandflies
41
What NTD's do bacteria cause?
1. Buruli ulcer – Mycobacterium ulcerans- Where skin and bone get destroyed
2. Leprosy – Mycobacterium leprae - Affects the peripheral nerves and skin with 250,000 people at risk
3. Trachoma – Chlamydia trachomatis- A contagious bacterial infection of the eye in which there is inflamed granulation on the inner surface of the lids.
4. Yaws - Treponema pallidum subspecies pertenue- Related to syphilis and is not sexually transmitted. Affects the skin, bone, and cartilage
42
What NTD's do viruses cause?
1. Dengue/Severe dengue- Fever, headache, and small # of cases, hemoragic fever
2. Rabies- Kills in Asia and Africa and causes 60,000 deaths. A contagious and fatal viral disease of dogs and other mammals that causes madness and convulsions, transmissible through the saliva to humans.
43
What are some features of NTD's?
Are a diverse group of diseases with distinct characteristics that thrive mainly among the poorest populations. The 17 NTDs prioritized by WHO are endemic in 149 countries and affect more than 1.4 billion people, costing developing economies billions of dollars every year.
44
What is the bottom billion?
We have 7 billion people and the bottom billion is 1.4 billion and they live on less than $1.24 a day. 50% of the world's population live on $2 a day
45
Describe the equation for Disability-adjusted life years (DALYs)
```
# of healthy years lost due to disability and premature death. DALY- YLL (years life lost) + YLD (years lived with disability)
- Japanese life expectancy is used so we can make comparison between diseases
```
46
What are some control strategies for NTD's ?
1. Rapid Impact Packages - 4 drugs targeting 7 diseases for less than 50 cents per year. a blister pack of pills. There are 4 drugs in a pack. They were brought to Africa, Asia, and South America.
2. Helen Keller International- To get the drugs to the people with the Hellen Keller International Organization
47
What were the project steps to distribute the pills to the infected people?
1. First they need to map where the disease is then advocate for the government to approve
2. People need to be trained to handle the medication to the infected people where their are health district team
3. The health district team trains the health staff then train the community distributors
4. Social mobilization that the drugs have arrived safely
5. People need to be safe and appropriate
6. Kids threw up after taking the pill
7. People were dosed based off their height
48
1. Which of the following are soil-transmitted infections?
1. ascariasis
2. hookworms
3. onchocerciasis
4. trachoma
5. Buruli ulcer
```
A. 1 and 2
B. 1 and 3
C. 2 and 4
D. 1, 2, and 4
E. 2, 3, and 5
```
A. 1 and 2
49
Which of the following correctly describes the “Big Three” diseases?
A. They are common in the United States
B. Malaria and tuberculosis are included in this group.
C. They do not receive large amounts of research funding
D. They are not included in the Millennium Development Goals
E. Schistosomiasis, ascariasis, and leprosy are in this group.
B. Malaria and tuberculosis are included in this group.
50
Trematodes: Taxonomy?
1. Phylum Platyhelminthes
2. Class Trematoda
3. Subclass Digenea
51
Trematodes: General life cycle?
Host>eggs>Miridium>Snail>>Sporosis>Redia>Cicada>/Meta Cicadia>Adult worms inside stomach of definitive host
52
Trematodes: Morphology?
1. Acoelomate- An invertebrate lacking a coelom; especially : one belonging to the group comprising the flatworms and nemerteans and characterized by bilateral symmetry
2. Parenchyma- Comprises the functional parts of an organ
3. Lack circulatory, skeletal, and respiratory systems
4. Respiration by diffusion
5. Digestive tract
6. Ventral sucker- Helps the worm stay in place
7. Nervous system
8. Reproduction- Sexual
53
Trematodes morphology: For parenchyma, what is the difference between fixed cells and stem cells?
1. Fixed cells- A usually large, irregular, and branching phagocytic cell existing in certain tissues (as connective tissue), lymph nodes
2. Stem cells- An undifferentiated cell of a multicellular organism that is capable of giving rise to indefinitely more cells of the same type, and from which certain other kinds of cell arise by differentiation
54
Trematodes: (Tegument) What are the 3 regions of the syncytium?
1. Glycocalyx- Surface area, glycoproteins, ivaginations, hydrolysis enzymes defense
2. Distal cytoplasm- Anucleate, 2 types of membranous bodies, multilamellar venclam and discoid bodies, There is a muscle layer that can be circular and longitudinal
3. Proximal cytoplasm- Nuclei and organelles. Produces substances that maintain distal cytoplasm and IS connected to distal cytoplasm by connective. Glycolate on top, distal cytoplasm in the middle, and proximal on the bottom.
55
Trematodes: What do the tegumental muscles-do?
Helps protect against digestive enzymes in those species that inhabit the gut of larger animals.
56
Trematodes: How do they have glucose uptake by tegument in schistosomes?
1. Adult worms in host’s bloodstream
2. Specific glucose transporters- Are integral membrane proteins. They are in all organisms across a hydrophobic surface membrane (concentration gradient)
3. Schistosome tegument- Surrounded externally by a lipid bilayer. And internally by a basal membrane.
57
Trematodes: (Teguments) What are the 2 types of schistosome GTP's?
SGTP1- In basal bilayer
| SGTP4- In lipid bilayer
58
Trematodes: How does foodborne trematodiases get ingested and where does it live in the body?
1. Ingestion by DH- Infected by intestinal parasites with food
2. Specific habitats within host environment- Once inside DH each sp liver has a specific habitat (Intestinal flukes- liver, bile duct, and gall bladder, lung flakes)
59
What is Clonorchis sinensis?
Oriental liver fluke, 19 million infected
60
Clonorchis sinensis: Life cycle?
1. Egg eaten by snail
2. Fish second IH
3. Humans are DH
61
Clonorchis sinensis: What is its pathology?
Adult worms
- Live in bile duct, erosion of bile duct, leads to thickening and blocking of bile duct.
- This leads to liver enlargement known as hepatoluesaty. The degree of pathology is having between 100 and 1000 worms and you get sick with nausea, diarrhea, abdominal pain
62
What is Fasciola hepatica?
Known as the sheep liver flu. It is the parasite of cattle and sheep. The reservoir hosts are non human definitive hosts and doesn't need humans. The reservoir hosts are the source of infection.
63
Fasciola hepatica: What is its lifecycle?
(Infects between 2-17 million people worldwide. Is rare in the U.S. Cattle and sheep raised.)
1. The IH is the snail
2. The metacercania encysts on plants. Plants are NOT hosts (Waterpress- Important source of infection that humans like to eat)
3. Metacercariae ingested by DH and exists in SI
4. The juvenile penetrates intestinal wall and immigrates through abdominal cavity 5. Penetrates the glissuis capsule that surrounds liver.
6. In the liver they migrate feed and grow and then they migrate to the bile duct when they are an adult.
64
Fasciola hepatica: What body characteristics does it have?
1. Oral sucker- Draws the host's tissue to break capillaries in the digestive tract
2. Gastrodermis- Single layer of epithelial cells line digestive tract. There is also cyclical transformation where it has:
(a. ) An absorptive phase- Is a surface layer that absorbs blood
(b. ) Secretory phase- The enzymes break down the blood and the Golgi becomes active for metabolism.
65
Fasciola hepatica: What is its pathology for juveniles?
1. Juveniles-With an ectoparasite in the wrong location. In the eye, skin, lungs, brain, and eye. 2. Acute fascioliasis- Migration through the liver and destroys liver tissue to feed on blood and causes the liver to swell to the point it would rupture. It occurs in 8 weeks after infection.
66
Fasciola hepatica: What is its pathology for adults?
Chronic fascioliasis- adult worms, 12 week for symptoms, in bile duct and damaging tissue. They secrete proline which is an amino acid and affects the host by stimulating host collagen deposition. It stimulates production of fibrous tissue.
2. Bile duct- This make the bile duct harden and blocked which is called pipe stem fibrosis.
CAUSES Jaundice- yellowish skin, bilirubin levels in blood and breakdown in the bile duct and urine
3. fascioliasis – emerging parasitic disease
67
What is Paragonimus westermani?
Oriental lung flu
68
Paragonimus westermani: What is its life cycle?
The life cycle:
- The first IH is the snail, microcercas circarious and has a knob tail and can't swim.
- The 2nd IH are crabs and cray fish, then the DH is humans and their are reservoir host like cats and dogs.
69
Paragonimus westermani: What is its pathology?
1. Lung necrosis- Necrosis of lung tissue, with chest pain, cough, and blood in the sputum. The ecto sites are juveniles that end up in the heart and brain
70
Metagonimus yokagawai and Heterophyes heterophyes: What is its life cycle?
The life cycle begins with the IH which is the snail, the 2nd IH is fish. They are very small and generally harmless in small number but not in large where they can cause ulcers. The eggs from these creatures can get into the blood and this can lead to heart failure and be in the brain and spinal cord.
71
Metagonimus yokagawai and Heterophyes heterophyes: What is the pathology?
1. Adults - inflammation and ulceration
2. eggs - ectopic sites- The eggs are in the host's feces
- There is environmental contamination
72
Metagonimus yokagawai and Heterophyes heterophyes: How do you diagnose it?
1. Route of exit from host- Feces
2. Direct wet smear- with 2mg feces, drop of saline, and look under the miscoscope. If there's nothing there and you have the infection it's called a false negative.
3. Formalin-ethyl acetate sedimentation concentration- detect a small # of eggs and this technique preserves the specimen. This technique extracts debris and fat. In this method you mix about 4 grams of feces and strain it through gauze, add saline, centrifuge, and discard the supernatent, add formalin, ethyl acetate, and discard the supernatent again and examine it for parasitic eggs.
73
Metagonimus yokagawai and Heterophyes heterophyes: How do you treat and control it?
1. Praziquantel- Praziquantel in the 1970's and is very safe, there is a precise mode of action where the worms go through rapid strain contraction where they can't move and get flushed out and the infection is gone.
2. Effects of drug on worms- Kill the adult worms with drugs with quaziquatel, don't use night soil which is human feces fertilizer. Have sanitation, removing snails, molluscicides with copper sulfate.
3. Possible mode of action- Boil any vegetation that grows in water to prevent the sheep liver flu for example.
74
Explain how transmission works and passive transmission
Transmission- Movement from host to ensure survival of generations
Strategies- Infection is acquired through contaminated food or water
Passive- Chance encounter and success is highly dependent on the abundance of the infected stages
75
What are some contamination strategies?
1. Sexual Transmission- No exposure to the external environment where there is no specialized transmission stage. An example with this is trichonomas vaginats
2. Congenital Transmission- Infection in the eggs and going from one generation to the next. An example of this is toxoplasma goudii, crosses the placenta, and affects the human embryo and goes into the brain.
3. Active transmission- A free living infective stage and is actively search for and invading a host. It requires a reliably high density of hosts and identify it well.
4. Mechanical Vector- One in which the parasite does not undergo development and stay on the surface. For example, flies.
76
What are the factors that deal with manipulation of host behavior?
PITT- The effect of parasite on its host which increases its chances that the host will be infected
Leuchochchloridium- When a snail is infected with the parasite where they have tentacles that get large because of the cercaria and they swell and birds eat them. Then the birds are the next host in the parasite life cycle.
77
Describe the transmission in the trematode life cycle with the egg
Trematode Transimission- They are oval shaped and exits the DH, enters the embyo called the micro muricedium, it then hatches when the external conditions are different from those inside a host. Hatching is usually stimulated by light which is usually outside the body.
78
Describe the transmission in the trematode life cycle with the miracidium
They have cilia which helps them swim, sensory nerve endings, glands that secrete enzymes where they penetrate into the snail and are germinal cells to produce the next larval structures.
79
What are the behavior of trematodes through their life cycle?
They have 24 hours to infect a snail host, they can find one by certain environmental cues such as light, Gravity, and temperature. These behavioral responses are the same as the snails. When it gets close, there is fast swimming and stays in the snails active space. It then penetrates the snail tissue. The parasite then loses its cilia and has a new Tegument and absorbs tissue to get nutrients. This is where having surface area helps.
80
What is a sporocyst and redia?
Sporocyst- A parasitic fluke in the initial stage of infection in a snail host, developed from a miracidium.
Redia- Exit the sporosis, but it the snail. They will either produce daughter, 2nd degree redice.
81
Circaria: What is its morphology and behavior?
Morphology: Cercaria has a tail and a head for its morphology
Behavior: Behavior- All spp must exit the snail.
Escape glands- Secrete enzymes where it can lyse snail tissue
External environment- Short lived (1-3 days), they swim or crawl, they find a place to encyst OR find the next host
82
What are 3 ways circaria can develop?
1. Development with encyst on plants, snails often live near vegetation, the circaria attach to the plant with post antagular glands and produces mucus to adhere to the plant. It then creates a cyst to that results into a metacercaria.
2. They penetrate 2nd IH and become a metacercaria. Then Infect 2nd IH, Cystogenus glands, metacercania, migrate in the definitive host
3. Penetrate a definitive Host and becomes an adult worm
IN BOTH B+C. They must find a suitable host. For their spatial location, the use cues such as light a gravity as to where the host may be.
83
Hoe would you describe the location for circaria?
1. Temporal location- Circadian release from the snail at certain times of the day. These times correspond to when the host is more likely present.
2. Infection of host- Post- acetabueler glands, mucus for attachment, sheds tail, pre-acetabular glands, secrete enzymes, lyse host tissue
84
How do circarial succeed and give an example?
Ex: Schistisome- A species of trematode where each infects a particular host
Bird Shistisomes- Where a cercaria is seeking a bird in H2o
1. It finds the bird by movement, shadow, warmth, and skin chemicals
2. It ALSO finds a human- movement, shadow, warmth, and skin chemicals
3. Cicaria can penetrate a human and result in a itch rash called swimmer's itch/Cercarial dermathis
85
What is the basic structure for metacircaeria?
Structure- Cyst wall, cytegenous glands, multilayered, spp that encyst plants. The wall is thick and can withstand environmental conditions
86
How does H. Polyeubramy reproduce?
Asexual reproduction that results in multiple offspring from 1 embryo,
1 egg goes to 1 miracedium
1 sporosis goes to some daughter sprocytes
Many radiae which makes many circariae
Where then it makes many many metacercaria
87
```
Which of the following stages exits the snail host during a trematode life cycle?
A. miracidium
B. redia
C. sporocyst
D. cercaria
E. egg
```
D. Cercaria
88
Ascaris suum is a parasite which produces thousands of eggs per day. These eggs remain in the soil or contaminate food until they are ingested by the definitive host. Sometimes these eggs remain in the external environment for years before they enter the host. Based on this information, what can you conclude about this parasite?
A. The eggs probably have a very thin wall
B. The parasite has evolved adaptations for the identification of suitable hosts
C. This is probably a blood-dwelling parasite
D. The success of the life cycle is dependent on environmental contamination
E. This is an example of vertical transmission
D. The success of the life cycle is dependent on environmental contamination
89
What are 3 species of blood flukes in humans?
1. Schistosoma mansoni
2. S. haematobium
3. S. japonicum
90
Name some little facts about blood flukes
1. They are in the NTD
2. They live in the circulatory system of the definitive host
3. Cause schistosomiasis= Shail fever, bilharzaisis
4. Affects 17 million people
91
What are some differences between schistosomes and other trematodes?
1. They are dioecious (male and female parts)
2. Live in the blood vessels
3. No rediae stage
4. No metacicaria phase
5. Only human trematode that is not food borne
92
Blood Flukes/Shistosomes: What is the life cycle?
Eggs
Shistosome Hemotopia- Has a terminal spine (large)
Shistisome Mantaline- Has a lateral spine (medium)
Shistosome - Lateral knots (small)
Hatching
When they are in fresh water, that will stimulate the cillia and beat very rapidly
This will cause the miracidium to spin. Suture- Line along the eggshell, then it breaks open
Miracidium- Is either female or male that infects a snail
Sporocyst- Produces daughter sporocysts
No rediae (A larva of certain trematodes) and circadia are reproduced
93
Blood Flukes/Shistosomes: What is the morphology?
1. Morphology- Head glands to escape and exit the snail, post acetabular that produce mucus and attach to the DH
2. Pre- acetubular- secrete enzymes and produce mucus and goes in DH
3. Tail
After it penetrates with the DH, it sheds its tail and loses glycocalate which was protecting against hypo-osmodic.
94
Blood Flukes/Shistosomes: What are the adults behavior?
Migrate to hepatic portal veins in liver then reach sexual maturity
Mesentary- Suspending the organs for 10-30 years
95
Blood Flukes/Shistosomes: What is their morphology?
1. No phargymy, ingest blood
2. Dioecious, sexual dimorphic
3. The male is shorter and wider than the female
4. Male- Have a gynecopheral canal (groove)
5. Shisto- Split
6. Soma- Body
7. Female is thinner than the male and they attach for continuous mating
8. Do not sexually mature
96
Blood Flukes/Shistosomes: Describe the habitat for adult worms
```
SH lives on veins of urinary bladder
SM lives in veins in intestin
SJ lives in veins of small intestine
1. Schistosoma mansoni
2. S. haematobium
3. S. japonicum
```
97
Blood Flukes/Shistosomes: How do the eggs exit?
1. The adult worms move as a pair into smaller veins until they become too big
2. The female then separates to go into thinner veins and lays eggs
3. Migrates back to any male after 40 years for genetic diversity
4. Eggs must get out of the vein and into the intestinal bladder
5. Eggs are in the veins and they can move since they can be call endothielial cells
98
Blood flukes/Shistosomes: How does the Cercarial dermatitis and its eggs exit the definitive host?
1. SEA soluable, egg, antogens which is released through pores that are in the eggshell
Their are proteins and enzymes
2. The SEA stimulate graduloma to form around the egg
3. Granduloma- Carries the egg from the circulatory system to the digestive system where they can disperse out of the body
4. Exit from the DH
⅔ of the eggs don’t make it through
This results in pathology
99
Shistosomes/Ciracaria: What is its pathology?
1. Transmission phase with circaria
2. Cercarial Dermatitis- Penetrates into the skin
3. Main pathology- Eggs transport in gut/bladder wall, can get swept through bloodstream, liver and spleen
100
What is the Granulomatous response?
1. SEA (soluable, egg, antogens)
2. Immune cells surround the eggs
3. Fibroblasts- Connecting tissue
101
What does the Granduloma do?
1. Protects the host from toxic substances released from the egg/miracidium
2. It is costly for pathology
3. Affects circulation
4. Normal functions impairs
5. Leads to an extra lobe on the heart
102
How does the disease Shistosome Hemotoma do to the body?
1. Fibrosis of uretes and bladder
2. Back pressure of urine that reaches the kidney
3. This may cause bladder cancer and colon cancer
103
How do you diagnose shistosomes?
```
SM and SJ- Eggs in feces
SH- Eggs in urine and feces
Shistosoma Hemotobium- Blood in urine
1. Schistosoma mansoni
2. S. haematobium
3. S. japonicum
```
104
How do you treat shistosomes?
1. Praziquantel- Immune response
2. Causes damage to the tegument of the adult worms and the cecum
3. Vaccine- Chemotherapy
4. Integrate chemotherapy with vaccination
105
How do we control shistosomes?
1. Kill adult worms with drugs
2. Sanitation
3. Snail control which is almost impossible to do
4. Boots and gloves
5. Education
106
In which of the following is the schistosome species correctly paired with one of its characteristics?
A. Schistosoma haematobium – lateral spine
B. Schistosoma japonicum – main pathology caused by eggs
C. Schistosoma mansoni – small, round egg
D. Schistosoma haematobium – monoecious
E. Schistosoma japonicum – no sporocyst stage
B. Schistosoma japonicum – main pathology caused by eggs
107
How do Schistosoma mansoni eggs exit the host?
A. Carried by the adult female into the intestinal lumen
B. Spine on the egg digs through the intestinal wall
C. Egg hatches in the vein and the miracidium chews through intestinal wall
D. Endothelial cells exclude egg from vein and a granuloma carries egg into intestinal
lumen
E. Eggs are swept through the circulatory system into the lungs and are then coughed up
and spit out
D. Endothelial cells exclude egg from vein and a granuloma carries egg into intestinal
lumen
108
What are some fun facts about immune responses?
1. Hosts have defenses to have immunity
2. Innate resistance- Natural immunity
Immunity are in all animal group
109
What are some non-specific responses for immunity?
1. Associated with the external surface of the animal like feather and scales
2. Provide a physical barrier to some ectoparasites.
3. Skin is a physical layer which is layers and layers of dead cells
4. It is also a chemical barrier of salts and acids
110
What are some internal defenses for internal defenses?
1. Releases substances that act as chemo attractants
2. Attract phagocytic cells (nemophils and macrophages)
3. Internal defenses for innate resistance
The snail can distinguish between self and non-self
4. Hemotode defense against hemotode larvae, they are sticky, encapsolate sporocis’s
They can the release cytotoxic neuro invaders
111
What are some antibody responses for schistosome infections?
1. Specific proteins in response to specific p. epilapes
| 2. The antibody combines with the epitode on the surface
112
How do cells have cellular immunity?
Combine with specific epitodes
Specific immune responses
Antibody and cellular responses to tegument
Absorb host molecules from serum to tegument
113
How does the host acquire resistance to reinfection?
Shistosomulum in body
Host produces antibodies and that response is going to kill some schistobobulum
Antibodies are present, but they do not attack the adults because they look like hosts
They are going to be extremely vulnerable to antibodies
114
What is the hygiene hypothesis?
1. Industrialized countries since 1960’s
2. Rapid increase in allergic and autoimmune diseases
3. Type 1 diabetes
115
What did Dr. David Strattau suggest?
1. Children from larger familes had lower ecezema than single child families
2. Greater exposure to microbialinfections
3. Allergies less common is rural area and underdeveloped countries
