Arthropodborne Infectious Diseases Flashcards
Describe Arthropods: Kingdom, Phylum ,and Class.
Give examples of organisms in each class
Kingdom Animalia
Phylum Arthopoda
-> Class Insecta: lice, fleas, mosquitos
-> Class Arachnida: spiders, mites, ticks
What are some GENERAL factors that make arthropod vectors adaptable?
What is the goal of arthropod vector adaptation?
- Multidevelopmental stages/complex lifecycle
- Diverse habitats (land/water)
- Several types of vertebrate hosts (reservoirs; human/rodent/deer)
Goal: Enhance survival of anthropod vector
Name 3 types of adaptations of anthropod vectors
Decribe each one
Physiological adaptations
- kissing buge detect host chemicals (CO2 -> bites around neck/mouth)
- Mosquitos bite and release chemicals (numb/dissolve/promote clots) before and after blood meal
Behavioral adaptations
- Mosquitos bites host at appropriate times (night/not moving)
Structural adaptations
- Wings (escape/loc nutrient source)
- Compound eyes (multiple lenses = 360 view)
- Needle (proboscis) = take blood meal
- Sensory bristles = detect viration of source (escape, loc nutrient source, mating)
GENERALLY name the 4 developmental stages (forms) of the Tick that causes Lyme Disease
Understand which one is uninfected/infected. Which one(s) is/are ALWAYS uninfected/infected?
Know which developmental stages develop in Year 1 and Year 2 of the Tick Anthropod Vector lifecycle
Know how many blood meals are taken by ticks. Which stage(s) take which blood meal?
-
Egg - YEAR 1
- Uninfected; always uninfected -
Larvae - YEAR 1
- Uninfected and Infected
-> Uninfected larvae = 1st blood meal (of infected field mouse) -
Nymph - YEAR 2
- Infected; always infected
-> 2nd blood meal (on human/pet = HUMAN/PET DZ) -
Adult - YEAR 2
- Infected; always infected
-> 3rd blood meal (on deer)
NYMPH IS THE INFECTIOUS STAGE THAT CAUSES LYME DISEASE IN HUMAN/PET
How long does it take to complete the tick lifecycle?
How many total blood meals are taken by the Tick anthropod vector?
- 2 years
- 3 blood meals
Describe Stage 8 of the Tick Anthropod Vector Lifecycle that causes Lyme Disease; refer to on the diagram.
Know the year and season of the lifecycle, and if the developmental stage exists are uninfected/infected. Be very specific.
Infected adult female tick (carrying Borrelia burgdorferi) lays uninfected eggs in the ground during Spring, Year 1.
Describe Stage 1 of the Tick Anthropod Vector Lifecycle that causes Lyme Disease; refer to on the diagram.
Know the year and season of the lifecycle, and if the developmental stage exists are uninfected/infected. Be very specific.
Uninfected egg hatches and develops into uninfected larvae in Spring, Year 1
Describe Stage 2 of the Tick Arthropod Vector Lifecycle that causes Lyme Disease; refer to on the diagram.
Know the year and season of the lifecycle, and if the developmental stage exists are uninfected/infected. Be very specific.
Uninfected larvae takes 1st blood meal on infected wildlife host, like infected field mice (natural reservoir) that have Borrelia burgdorferi during Summer, Year 1
Infected larvae is now infected with B. burgdorferi
Describe Stage 3 of the Tick Anthropod Vector Lifecycle that causes Lyme Disease; refer to on the diagram.
Know the year and season of the lifecycle, and if the developmental stage exists are uninfected/infected. Be very specific.
After first blood meal, infected larvae with Borrelia burgdorferi detaches from wildlife host (field mice) and drops to ground.
Remains dormant during Fall and Winter, Year 1 because cold weather and lack of availiablity of field mice
Describe Stage 4 of the Tick Anthropod Vector Lifecycle that causes Lyme Disease; refer to on the diagram.
Know the year and season of the lifecycle, and if the developmental stage exists are uninfected/infected. Be very specific.
Infected larvae (containing Borrelia burgdorferi) comes out of dormant stage and develop into infected nymph during Spring, Year 2
Describe Stage 5 of the Tick Anthropod Vector Lifecycle that causes Lyme Disease; refer to on the diagram.
Know the year and season of the lifecycle, and if the developmental stage exists are uninfected/infected. Be very specific.
Infected nymph with Borrelia burgdorferi takes its 2nd blood meal on uninfected human/pet (who are usually outdoors) during Summer, Year 2
Human/pet now infected with Borrelia burgdorferi and human will develop lyme disease
NYMPH IS THE INFECTIOUS STAGE OF THE TICK THAT CAUSES LYME DZ
Which developmental stage of the Tick Anthropod Vector is the infectious stage that gives human Lyme Disease
Infected Nymph, when it takes its 2nd blood meal during Summer, Year 2
Describe Stage 6 of the Tick Anthropod Vector Lifecycle that causes Lyme Disease; refer to on the diagram.
Know the year and season of the lifecycle, and if the developmental stage exists are uninfected/infected. Be very specific.
Infected nymph detaches from human/pet after its 2nd blood meal.
Develops into infected adult tick during Fall, Year 2
Describe Stage 7 of the Tick Anthropod Vector Lifecycle that causes Lyme Disease; refer to on the diagram.
Know the year and season of the lifecycle, and if the developmental stage exists are uninfected/infected. Be very specific.
The infected adult tick with Borrelia burgdorferi has its 3rd blood meal on uninfected wild animal (deer) during Fall, Year 2.
Deer is now infected with Borrelia burgdorferi
Infected adult ticks mate
Describe this Airborne Disease: Plague
(AKA/Causative Agent/Characteristic, Reservoir, Mode of Transmission, Predisposing Factors, SXS, Diagnosis, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: Black Death
- CA: Yersinia pestis
- Characteristic: Gram-negative, bacillus
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1°: Rats, wild rodents
- 2°: Humans
Mode of Transmission
- Rat flea vector
-> Bacteria in rat -> spread to rat flea -> humans DZ
Predisposing Factors
- Poor sanitation
Incubation Period
- x
SXS
- Bacteremia (Sys Inf)
Diagnosis
- Serology
- Lung sputum sample
- Fluid aspiration from buboes
Treatment
- High dose ABX
Preventative Measures
- Pest control (eliminate the reservoir/rat)
- Plague Vaccine
-> use for high-risk people
-> only effective against bubonic plague
MISC
- Endemic to parts of the US (dry areas; Southwest)
-
Bubonic Plague:
-> Bact grows in macrophage -> bacteremia -> target lymph nodes
-> Hard/swollen lymph nodes (axilla/groin) = buboes
-> Hemorrhaging (skin turn black/purple)
-> Most common plague
-> Large mortality (50+%) -
Septicemic Plague:
-> Septic shock b/c bacteremia -
Pneumonic Plague:
-> Droplet/airborne transmission
-> Bacteremia -> lungs
-> High mortality (if not treated immediately)
Describe this Airborne Disease: Lyme Disease
(Causative Agent/Characteristic, Reservoir, Mode of Transmission, SXS, Diagnosis, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Borrelia burgdorferi
- Characteristic: Spiral shaped, spirochetes (endoflagella/axial filaments), motile
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1°: Field/deer mice
- 2°: Deer
Mode of Transmission
- Tick vector
-> Bacteria in mouse/deer -> spread to tick -> humans DZ
Predisposing Factors
- x
Incubation Period
- x
SXS
- First phase:
-> Bullseye rash (flat/ alternating bands pale/red) - Second phase:
-> Facial paralysis
-> Irregular heartbeat
-> Encephalitis
-> Flu-like SXS - Third phase:
-> Arthritis (from immune response)
Diagnosis
- Based on clinical SXS
- Serology
- Prevalence in geographic areas (NE USA)
Treatment
- ABX
-> For first stage (more difficult to treat in later stages)
Preventative Measures
- Protective clothing
- Tick repellent
- Avoid rodents & deer
MISC
- Most common tickborne DZ in U.S.
- High incidence = Summer
- Prevalent = Northeast U.S.
- Known DZ since 1975
Describe this Airborne Disease: Epidemic Typhus
(AKA/Causative Agent/Characteristic, Reservoir, Mode of Transmission, Predisposing Factors, SXS, Diagnosis, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: Typhus Fever
- CA: Rickettsia prowazekii
- Characteristic: Gram-negative bacillus or coccobacillus, obligate intracellular parasite (reproduces inside host/replicate only in humans)
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- Human body louse
Mode of Transmission
- Louse vector
-> Bacteria inside human body louse -> humans DZ
-> Transmitted when louse feces are rubbed (by human) into the bite wound
Predisposing Factors
Lack of hygiene:
- Wars
- Homelessness
- Crowded Jails
- Concentration camps
Incubation Period
- x
SXS
- Prolonged high fever
- Spotted rash
-> Subcutaneous hemorrhaging
-> Chest/trunk -> extremities
Diagnosis
- Type of rash & location
- Serology
Treatment
- ABX
Preventative Measures
- Good personal hygiene
MISC
- High mortality if left untreated
Describe this Airborne Disease: Rocky Mountain Spotted Fever (RMSF)
(Causative Agent/Characteristic, Reservoir, Mode of Transmission, Predisposing Factors, SXS, Diagnosis, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Rickettsia rickettsii
- Characteristic: Gram-negative bacillus or coccobacillus, obligate intracellular parasite (reproduces inside host/replicate only in humans)
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- Tick
Mode of Transmission
- Tick vector (different tick than Lyme DZ)
-> Bacteria in tick -> humans DZ - Transovarian passage
-> Inf adult female tick -> lays inf eggs -> hatch into inf larvae -> inf nymph
Predisposing Factors
- Outdoors
- Hiking
Incubation Period
- x
SXS
- Fever
- Spotted rash
-> Subcutaneous hemorrhaging
-> Extremities (palms & soles) -> chest/trunk
Diagnosis
- Type of rash & location
- Serology
Treatment
- ABX
Preventative Measures
- Protective clothing
MISC
- Infected nymph responsible for RMSF
- Common in the Southeast & Appalachian Mountain Region
Describe this Airborne Disease: Malaria
(Causative Agent/Characteristic, Virulence Factor, Reservoir, Mode of Transmission, Predisposing Factors, SXS (how do these SXS come about?), Diagnosis, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Genus Plasmodium
- Characteristic: Kingdom Protista, Subkingdom Protozoa, protozoan parasite
-> P. vivax = mildest and most common for to cause DZ
-> P. ovale = endemic
-> P. malariae = endemic
-> P. falciparum = most deadly; severe anemia and encephalitis (Cerebral malaria)
Virulence Factors
- Complex lifecycle
- Long, slow blood cycle
- Frequent gene mutation -> high drug resistance
Tissue/Organ Affected
- x
Reservoir
- Human
Mode of Transmission
- Mosquitos (arthropod vector)
Predisposing Factors
- Tropical climates/along equator
- Stagnant water where mosquitos deposit eggs
Incubation Period
- x
SXS (due to paroxysms/rupturing RBC by merezoite form)
- Intermittent fever, spiking every 48-72 hours
- Anemia
- Weakness
- Fatigue
- Chills
- Sweating
Diagnosis
- RBC with typical “ring form” of Plasmodium (merozoites)
Treatment
- Antiparasitic/Antimalarial
-> Chloroquine (limitations bc drug resistnace)
-> Artemisinin derivatives (Chinese herb)
Preventative Measures
- NO VACCINE IN US
-> Goal: Vaccine by 2030 - Vector Control
- Mosquito repellent
- Mosquito nets
- Clearing stagnant water
MISC
- ONE OF THE MOST COMMON CAUSE OF DEATH INVOLVING INFECTIOUS DISEASE (#2) = kills thousands/year
Describe this Airborne Disease: West Nile Encephalitis (Arboviral Encephalitis)
(Causative Agent, Reservoir, Mode of Transmission, SXS, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: West Nile Encephalitis Virus
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1° = birds (crows); rodents
Mode of Transmission
- Bite from mosquito
Predisposing Factors
- x
Incubation Period
- x
SXS
Mostly Asymptomatic:
- Encephalitis
-> Neurological SXS - Polio-like paralysis
- Fever
- Headache
Diagnosis
- x
Treatment
- No treatment available
Preventative Measures
- No vaccine available
- Vector control
MISC
- All over the U.S.
- Portal of Entry = Skin
Describe this Airborne Disease: St. Louis Encephalitis (Arboviral Encephalitis)
(Causative Agent, Reservoir, Mode of Transmission, SXS, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: St. Louis Encephalitis Virus
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1° = Birds
Mode of Transmission
- Bite from mosquito
Predisposing Factors
- x
Incubation Period
- x
SXS
- Encephalitis
-> Neurological SXS - Fever
- Headache
Diagnosis
- x
Treatment
- No treatment available
Preventative Measures
- No vaccine available
- Vector control
MISC
- Portal of Entry = Skin
- Usually adults over 40 y/o
- Central U.S.
Describe this Airborne Disease: Eastern Equine Encephalitis (Arboviral Encephalitis)
(Causative Agent, Reservoir, Mode of Transmission, SXS, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Eastern Equine Encephalitis Virus
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1° = horses & birds
Mode of Transmission
- Bite from mosquito
Predisposing Factors
- x
Incubation Period
- x
SXS
- Encephalitis
-> Neurological SXS - Fever
- Headache
Diagnosis
- x
Treatment
- No treatment available
Preventative Measures
- No vaccine available
- Vector control
MISC
- Portal of Entry = Skin
- Southeast U.S.
- High mortality (30%) in humans
Describe this Airborne Disease: Yellow Fever (Arboviral Hemorrhagic Fever)
(AKA/Causative Agent, Reservoir, Mode of Transmission, SXS, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: Jungle Fever
- CA: Yellow Fever Virus
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1° = wild monkeys
Mode of Transmission
- Bite from mosquito
Predisposing Factors
- x
Incubation Period
- x
SXS
- Jaundice
- Rash
- BV damage
-> Hemorrhage in severe cases - Fever
- Muscle pain
Diagnosis
- x
Treatment
- No treatment available
Preventative Measures
- Vaccine available
- Vector control
MISC
- Portal of Entry = Skin
Describe this Airborne Disease: Dengue (Arboviral Hemorrhagic Fever)
(Causative Agent, Reservoir, Mode of Transmission, SXS, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Dengue Virus
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1° = humans
Mode of Transmission
- Bite from mosquito
Predisposing Factors
- x
Incubation Period
- x
SXS
- BV damage
-> Hemorrhage in severe cases - Rash
- Fever
- Muscle pain
Diagnosis
- x
Treatment
- No treatment available
Preventative Measures
- No vaccine available
- Vector Control
MISC
- Portal of Entry = Skin
Describe this Airborne Disease: Ebola Virus Disease (Emerging Viral Hemorrhagic Fever)
(Causative Agent, Reservoir, Mode of Transmission, SXS, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Ebola Virus
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1° = cave-dwelling fruit bats
Mode of Transmission
- Contact with infected animal blood & animal waste products
- Infected human body fluids
Predisposing Factors
- x
Incubation Period
- x
SXS
- BV damage
-> PROFUSE hemorrhage in severe cases - Rash
- Fever
- Muscle pain
Diagnosis
- x
Treatment
- No treatment available
Preventative Measures
- Vaccine available
MISC
- NOT SPREAD BY ARTHROPOD VECTOR
- Portal of entry - Skin
- Mortality rates 90%
- Originated from Ebola River Region in Africa
Describe this Airborne Disease: Zika Virus Disease (Emerging Infectious Disease)
(Causative Agent, Reservoir, Mode of Transmission, SXS, Treatment, Preventative Measures, Misc.)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Zika Virus
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- 1° = wild monkeys
Mode of Transmission
- Sexual
- Mother -> fetus
- Blood transfusions
- bites from mosquitos
Predisposing Factors
- x
Incubation Period
- x
SXS
- Mostly neurological SXS; some BV damage
- Pink eye (conjunctivitis)
- Rash
- Fever
- Muscle pain
Diagnosis
- x
Treatment
- NO TREATMENT available
Preventative Measures
- No vaccine available
- Vector control
MISC
- Portal of entry - Skin
- Originated from Zika Forrest region in Africa
- 2015 outbreak in Brazil
- Infection during pregnancy -> microencephaly (small brain in babies)
Name the different developmental stages (forms) for the pathogen that causes Malaria, Genus Plasmodium
Which developmental stage is the the human/mosquito.
Who is the definitive/intermediate host, and which type of reproduction occurs?
Sporozoite - mosquito and human
Merozoite - human
Male and Female Gametocytes - human and mosquito
Zyote - mosquito
Definitive host = mosquito = sexual reproduction
Intermediate host = human = asexual reproduction
Sporozoites are first found in who?
Male and female gametocytes are first found in who?
Mosquito - definitive host
Human - intermediate host
What is schizogony? Where does it occur and what developmental stage is produced at the end?
Schizogony = the division of sporozoites into merezoites
Occurs in the liver (of human)
Describe: Stage 1 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- The infected female mosquito, who has sporozoites (of Plasmodium) parasite in her salivary glands, has a blood meal on uninfected human
- Sporozoites from mosquitos salivary gland enter the human blood stream and travel to the liver
*Sporozoites are first detected in mosquitos
Describe: Stage 2 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- Sporozoites (of Plasmodium) parasite develop into merozoites in human liver cells via schizogony, which is the division of sporozoites into merozoites
- The human is the intermediate host where asexual reproduction of Plasmodium vivax lifecycle occurs.
Describe: Stage 3 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- Merozoites (of Plasmodium) are released from the human liver and move into the bloodstream where they can infect new RBC
- Humans are the intermediate host where asexual reproduction part of Plasmodium vivax lifecycle occurs
Describe: Stage 4 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- Merozoites (of Plasmodium) develop into the “Ring Stage” inside RBC
- A common diagnositc method for Malaria is observing RBC wih “ring formed” merozoites in a blood smear
- Humans are the intermediate host where asexual reproduction part of Plasmodium vivax lifecycle occurs
Describe: Stage 5 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- The “ring stage” of merozoites (of Plasmodim) grow and divide, producing more Merozoites
- Humans are the intermediate host where asexual reproduction part of Plasmodium vivax lifecycle occurs
Describe: Stage 6 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- Merozoites (of Plasmodium) rapidly divide, causing the RBC to rupture and release merozoites
- Symptoms of Paroxysms (intermittent fever/chills) occur in human
- Some merozoites can infect new RBC in the bloodstream OR can develop into male and female Gametocytes
- Humans are the intermediate host where asexual reproduction part of Plasmodium vivax lifecycle occurs
Describe: Stage 7 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- An uninfected, different mosquito takes a blood meal from the an infected human carrying Gametocytes (of Plasmodium).
- Mosquito is now infected by ingesting the gametocytes, which travel and are found in the mosquitos GI tract
- Mosquitos are the definitive host, where sexual reproduction of Plasmodium vivax lifecycle occurs
Describe: Stage 8 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- Male and female gametocytes (of Plasmodium parasite) will unite to form zygotes inside the infected mosquito’s GI tract
- Mosquitos are the definitive host, where sexual reproduction of Plasmodium vivax lifecycle occurs
Describe: Stage 9 of the Life Cycle of Plasmodium vivax
Include who is the definitive/intermediate host and what type of reproduction is taking place.
- Zygotes (of Plasmodium) develop into Sporozoites (of Plasmodium) that migrate to the salivary glands of an infected mosquito
- This is adaptive for the Plasmodium parasite so that the parasite can be delivered into the next host when the infected mosqutios takes another blood meal
- Plasmodium parasit remaining in the infected mosquitos GI tract is not helpful because it will not be able to pass along the parasite
- Mosquitos are the definitive host, where sexual reproduction of Plasmodium vivax lifecycle occurs
what is pulse oximetry?
- measures % of hemoglobin
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