Zoonotic Diseases Flashcards
What is the primary host, and the intermediate host of Taenia Solium?
primary: humans
intermediate: pigs
What are the different forms of Taenia Solum, and how are each transmitted?
Porcine cysticercosis: pigs ingest eggs, cysts in muscle
Human taeniasis: humans eat cysts in pork, adult tapeworm in GI tract
Human cystircercosis: humans ingest eggs
Neurocysticercosis: larvae encyst in brain
How is Taenia Solum transmitted to people?
Taeniasis: eating under-cooked infected pork
Neurocysticercosis: self infection, fecal, food, or water contamination
How do we prevent Taenia Solium?
- target vehicles
- proper cooking/handling of raw pork
- block transmission: hygiene
- treat people with tapeworms
- sewage management
What is Giardiasis?
- parasitic disease
- has one host life cycle: consume cysts, trophozites form and produce cysts
- chronic diarrhea in people
How is Giardiasis transmitted?
consumption of cysts
- water and surface of food contamination
How do we prevent Giardiasis?
- water and sewage treatment
- wash or peel veggies and fruit
What is Rabies?
- an acute, progressive encephalomyelitis
- caused by RNA virusus
- highest fatality, oldest disease
- furious form and dumb form
What are the principle reservoirs of Rabies?
Carnivora (canids, skunks, raccoons, mongoose) and Chiroptera (bats)
How do we prevent Rabies?
- surveillance of human and animal
- reduce animal reservoir by vaccination and control of feral populations
- reduce human risk with post exposure measures, vaccination, and education
What is Hantavirus?
Bunyaviridae: enveloped ssRNA viruses
What is the reservoir of Hantavirus?
rodents who are asymptomatic
How is Hantavirus transmitted?
- rodents shed virus in saliva, urine, and feces
- primarily aerosol: inhalation
- can be direct or indirect
- secondary transmission via bite
What is Hantavirus Pulmonary Syndrome, and what are its clinical signs in humans?
- new world disease
- fever, chills, myalgia, headache
- increased vascular permeability in lungs
- fatal in 40% of cases
What is Hemorrhagic Fever with Renal Syndrome, and what are its clinical signs in humans?
- old world disease caused by Hantavirus
- petechial hemorrhage, renal damage, and cardiovascular shock
- fatal in 15% of cases
How do we prevent Hantavirus?
reduce human and rodent contact
What is Anthrax?
- spore forming bacterium
- mostly effects cattle
What are the clinical signs of Cattle Anthrax?
- bleeding from all orifices
- swelling
- sudden death
How is Anthrax transmitted?
- inhalation of spores from soil or fomites
- herbivores: ingest spores in soil
- carnivores: eat infected herbivores
- veterinarians: aerosol of percutaneous exposure to blood of infected animal
How do we control Anthrax?
- no necropsy on suspected cases
- animal vaccination
- burn infected carcasses
- inform health officials
- advise exposed people to wash hands and iodine immersion
What are the types of Brucellocis?
- Brucella melitensis: most pathogenic to people, goat-farming regions
- Brucella abortus: more pathogenic to people, cattle, horses, and pigs
- Brucella suis: less pathogenic to people, pigs
- Brucella canis: less pathogenic to people
What are the clinical signs of Brucellocis in humans?
- undulant fever, Malta fever, or Bangs fever
- recurring fever, can last for months
- abortions can occur
- pleiomorphic symptims: neurologic, endocarditis, chronic fatigue
How is Brucellocis transmitted?
- ingestion, mucous membrane exposure, or percutaneous inoculation
- aborted placenta, fetal fluids
- unpasteurized milk
- blood, urine, semen, feces, vaginal secretions
- contaminated feed/water
How do we control Brucellocis?
- eliminate reservoir
- monitor swine
- pasteurization of milk
What is Borreliosis?
- tick transmitted spirochetes
- Lyme disease: Ixodes, hard ticks
- Relapsing fever type: soft ticks
Describe Borrelia burgdorferi
- Lyme disease
- vectored by Ixodes sp. hard ticks
- reservoir: sylvatic rodents
- disease in people, dogs, and horses
What are the clinical signs of Borrelia burgdorferi?
- acute: febrile illness, myalgia, arthralgia
- chronic: cardiovascular, neurological, joint problems
Explain the exposure of Borrelia burgdorferi
- outdoor activities
- ticks must be attached for 48 hours to transmit the disease
- infected dogs can serve as domestic sources of infected ticks
How do we prevent Borreliosis?
- avoid direct contact with ticks
- apply tick repellent
- remove ticks from body, pets, and clothes
Describe West Nile Virus
- genus: Flavivirus
- maintained in mosquito-bird-mosquito cycle
- horse and humans are dead-end hosts
- after infection, develop life-long immunity
How is West Nile Virus transmitted?
- mosquito bites infected bird and picks it up
- secondary transmission through blood-borne infection, lab exposure, and breast milk
- not spread through handling dead/ill birds
What are the clinical signs of West Nile Virus in horses?
neurologic: ataxia, hypermetria, weakness, recumbency, peri- or tetraporesis, death
What are the clinical signs of West Nile Virus in humans?
- most are asymptomatic
- 20% develop mild febrile illness
- 1/150 develop neuroinvasive disease
- 10% are fatal
