Final Exam Flashcards
Zoonoses
Diseases/infections naturally transmitted between animals and humans
Anthropozoonosis
Animal to human infection
-Rabies, brucellosis, cat scratch disease
Zooanthroponosis
Human to animal infection
- Tuberculosis to elephants, influenza to ferrets
What are zoonoses NOT
- Poisoning/envenomation by animals/insects
- Bites, kicks, or scratches by animals
- Allergies to animals
- Anthroponoses (diseases that people get from other people)
Where might zoonoses occur?
- Farm sites: close contact w/ livestock & their by products (milk, placenta)
- Animal processing facilities: slaughterhouses and processing plants
- Forestry/outdoors: wildlife habitat for professional or recreational reasons
- Recreation: contact with pets or wildlife
- Laboratories/clinics: handle specimens, tissues, carcasses
- Emergencies: catastrophes, refugees, temporarily living in crowded or high stress situations
Agent
Organism causing the disease
- Can act alone or in concert with other organisms
- Transient or persistent
Reservoir
“Carrier”; source of persistence in nature and infection in new hosts
- May/may not have symptoms
- Sometimes, may be environment itself
Amplifier
“intermediate host”
- High levels of agent replication
- Often in closer human contact than a reservoir
- Asymptomatic infections in many cases, but not always
- Most commonly associated with vector-borne diseases
Dead-end host
- Agent does not replicate to the level of necessary for further transmission
- Asymptomatic infections in many cases, but in some cases severe disease is possible
- Often associated with vector-borne diseases
Common bacterial zoonotic agents
Anthrax, brucellosis, lepto, plague, Q fever
Common viral zoonotic agents
COVID-19, influenza, monkeypox, rabies, west nile virus
Common fungal zoonotic agents
Dermatophytes, histoplasma, basidiobolus
Common prion zoonotic agents
Mad Cow Disease (BSE)
Common parasitic zoonotic agents
Protozoal: Toxoplasma, giardia
Helminths: Baylisascaris, trichinella
Arthropods: scabies
Dogs/Cats reservoir diseases
Rabies, roundworms, ringworm, cat scratch disease
Livestock reservoir diseases
Salmonella, E. coli, brucellosis, Q fever
Birds/Poultry reservoir diseases
Avian influenza, chlamydiosis, cryptococcus
Reptiles, fish, amphibians reservoir diseases
Salmonella, mycobacterium
Wildlife reservoir species
Rabies, hantavirus, plague, tularemia
Routes of zoonotic disease transmission
Direct contact: infected tissue, bite wounds, body fluids
Indirect contact: fomites, aerosol
Foodborne: contaminated food/water
Vectorborne: rodents, mosquitoes, fleas, ticks
“SIR” model of pathogenesis
Susceptible —(incubation period)—> Infected/symptomatic —–> Recovered, removed, or dead (immune, carriers, or remain susceptible)
*transmission = IR
How many nationally notifiable zoonotic diseases?
25
Notifiable zoonotic diseases
Reportable disease vary by locality
- National vs state
Examples: yersinia pestis (plague), rabies, bacillus antracis, myobacterium bovis, VEE
What is the cost of zoonotic diseases?
Cost to human health
- Lost productivity, loss of life due to disease
Economic costs
- Direct/indirect costs of prophylaxis & tx
- Cost of import/export restrictions
- Loss of trade and tourism