Lecture 16 - Vector and Soilborne Diseases Flashcards
When a vector transmits a disease from a non-human reservoir to a human, why is it rare for that newly infected human to transmit the disease to another human?
The pathogen reservoir not designed to be humans so usually dead-end host.
What are characteristics of soilborne diseases?
Usually fungal and bacterial pathogens
-can’t be eliminated because of unlimited reservoir
What is the Pathogen, Reservoir, and Transmission of Rabies?
Pathogen
-Rhabdovirus
Reservoir
-Domestic and Wild animals
Transmission
-infected animal bite
What is the Epidemiology and Pathology of rabies?
Epidemiology
-Virus in animal saliva
Pathology
-Proliferates in the brain
What are the symptoms and Diagnosis of rabies?
- excitation, anxiety, pupil dilation
- lab analaysis for negri bodies
- wild vs domestic animals
What is the treatment for rabies?
Passive Immunization
-rabies antiserum
Active Immunization
-Rabies vaccine
Combined almost 100 percent effective, early diagnosis is key
How do we prevent rabies?
Humans
-immunization of high risk individuals
Domestic Animals
-immunization
Wild Animals
-injected oral vaccines
What is the Pathogen, Reservoir, and Transmission of Hantavirus?
Pathogen
-Hantaviruses
Reservoir
-Rodents
Transmission
- infected animal feces
- feces dries out and goes airborne
What is the Epidemiology and Pathology of Hantavirus?
- Inhalation of fecal dust from infected animals
- Proliferates in the human body
- In US, low incidence but high mortality
- Outside of US, high incidence but low mortality
What are the symptoms and Diagnosis of Hantavirus?
- fever, muscle pain
- thrombocytopenia=decrease in blood platelets
- leukocytosis=increase in leukocytes
Can use lab tests
-cultures, ELISA, PCR
What is the treatment for Hantavirus?
No treatment or vaccines available
What are the biosafety level 4 pathogens?
Hantaviruses
Filoviruses like Ebola
VERY DANGEROUS
What kind of pathogen is ebola?
Genus Ebolavirus, family Filoviridae
What is the most deadly and most common species of ebola?
Zaire ebolavirus
How is ebola transmitted?
Natural reservoir thought to be fruit bats
Bat passes it to non-human primate
Human consumes non-human primate
Human to Human transmission
How is ebola transmitted via human-to-human?
Direct contact w/
- Blood/body fluids of infected
- Objects contaminated w/ blood/body fluids
Virus enters via broken skin or mucous membranes
Who are the high risk groups for contracting ebola?
Healthcare workers
Family/friends of infected
What are the symptoms of ebola?
Early symptoms similar to other commons diseases
Days 8-12= vomiting blood, brain damage, bleeding from orifices, organ failure, death
What diagnostic tests are available for ebola? How do we determine who to test?
Diagnostic Tests
-PCR, ELISA, Virus isolation
Symptoms + Exposure risk determines who to test
What are the treatment options for ebola?
None available
-recovery depends on immune response
Can maintain hydration and oxygen levels and treat secondary infections
How do we prevent ebola?
No vaccine available
Monitor and contain outbreaks
What is the Pathogen, Reservoir, and Transmission of Lyme Disease?
Pathogen
-Borrelia borgdorferi
Reservoir
-Mammals, mainly rodents
Transmission
-Vector, ticks
What is the epidemiology and pathology of lyme disease?
Untreated, disease reaches CNS
No toxins or virulence factors known
What are the symptoms and diagnosis for lyme disease?
Symptoms
- acute stage=rash, headache, chills, fatigue
- chronic stage=arthritis, neurological and heart damage
Diagnosis
- symptoms+tick exposure+rash
- ELISA, western blot, PCR
