Exam 2 Flashcards
An animate or inanimate object that serves as a long term habitat and focus of dissemination for an infectious agent
Reservoir
An individual or object from which an infection is actually acquired
Source of infection
Reservoir for Cryptosporidium parvum
Cattle
Source of infection for crypto parvum
Water
Exampe of a case where the reservoir and source are the same
Syphilis (humans are reservoir and source)
Objects that are able to transfer disease organisms
Fomite
Any live animal that transmits an infectious agent from one host to the next. Typically used to describe arthropod reservoirs
Vector
Vector type that actively participates in the pathogen’s life cycle
Biological vector
Vector type that is a passive participant in the transmission of disease
Mechanical
Spread of disease through a population from one infected individual to another (can be indirect or direct)
Horizontal Transmission
Spread of disease from parent to offspring via placenta, sperm, milk or ovum (always direct)
Vertical transmission
Example of direct contact transmission
Cat to human ringworm
Cat to human to cat is an example of what type of transmission?
Indirect contact transmission
A sneeze or a cough from infected to uninfected individuals is an example of what type of transmission?
Direct Airborne (aerosol) Transmission
A sneeze that contaminates a ventilation system that eventually infects animal/human is an example of what type of transmission?
Indirect Airborne (Aerosol) Transmission
Toxoplasma gondii and listeria monoctogenes are examples of diseases spread through which mode of transmission?
Placental
In placental transmission, the microbe can cross the placenta and enter the ____ ____ and spread disease
Umbilical vein
Placental transmission depends upon the ______ _____ and the ______ involved
Gestation stage and the microbe involved
Fomites spread disease through _______ transmission
Indirect
Bedding with E coli is an example of which type of transmission?
Fomites
Arthropods (vector transmission) spread disease through ______ transmission
Indirect
Disease classification that has severities and duration between acute and chronic. Accounts for some forms of anthrax.
Subacute Disease
Term for someone who studies the factors that determine the frequency and distribution of disease within populations
Epidemiologist
The number of new cases of disease in a defined population over a specific time period as compared to the general healthy population i a certain time period (typically over a year)
Incidence (morbidity rate)
Total number of cases in a population compared to the entire population
Prevalence
Formula for determining prevalence
Total number of cases in a population divided by the total number of individuals in a population X 100
Term for a disease always present within a population of a geographic area
Endemic disease
Disease affecting animals of specific geographic area. Constantly present in specific animal community but occurs in small number of cases
Enzootic disease
Term for disease with few isolated cases of disease in a widespread area in an unpredictable manner
Sporadic
Term for a sudden onset and widespread outbreak within a group
Epidemic disease
Term for a widespread disease in a population of animals other than humans. Spread rapidly, simultaneously affecting a large number of animals in a region
Epizootic disease
Term for a disease that is a widespread epidemic usually across continents
Pandemic Disease
Term for a widespread epizootic disease
Panzootic disease
United Nations organization for monitoring zoonoses
WHO (The World Health Organization)
What is the World Health Organization responsible for?
Promoting cooperation of health care among nations
Carry out disease control and eradication
Improve quality of human/animal life
This organization sends out teams of epidemiologists to investigate outbreaks and assist with bringing the outbreak under control
WHO
United States agency that functions to assist state and local health department in all aspects of epidemiology
CDC
Primary federal agency for conducting and supporting medical research
National Institutes of Health (NIH)
Line of defense that limits access to the internal tissues and organs of the body
First line of defense
What are the anatomic properties of the first line of defense?
Unbroken skin, Mucous membranes, Hairs and cilia
The second line of defense is composed of _______ and _______ protection
cellular and chemical
Fever stimulating chemical that could be bacteria, virus or parasites
Pyrogen
What are the benefits of Fevers?
Inhibit replication
Stimulate WBCs to destroy microbes, reduce iron available for bacterial replication
What are the disadvantages of fevers?
Increase HR, increased caloric demand, seizures, dehydration
Causitive agent of Anthrax
Bacillus anthracis
Non-motile, gram +, endospore forming bacilli
Conditions in which anthrax multiplies
60 degrees, heavy rainfall
Animals most commonly associated with the epizootic form of anthrax
Cattle, bison and deer (typically a disease of herbivores)
What are the three forms of anthrax?
Peracute, Acute and Chronic
Form of anthrax presenting with ataxia, dyspnea, trembling or sudden death. (Typically do not show any signs)
Peracute Anthrax
Form of anthrax in ruminants that produces localized edema, typically in the neck, thorax and shoulders.
Chronic anthrax
Form of anthrax causing lingual and pharyngeal edema and/or hemorrhage of the pharyndeal and cervical lymph nodes in swine
Chronic anthrax
Why should necropsies never be performed on animals suspected to have anthrax infection?
Spores form when exposed to oxygen
How are anthrax endospores destroyed?
Autoclaving, boiling for 30 minutes, expose to dry heat at 140 degrees for 3 hours, chemical disinfection at high concentration for a long period of time, cremation
Treatment for bite wounds
Clean, irrigate, debride, antibiotics (within 24 hours)
Disease also known as “Bang’s disease”, Contagious abortion, Matta Fever, or Mediterranean fever
Brucellosis
What species is resistant to Brucellosis?
Cats
Brucellosis in cattle is uncommon due to what in the US?
Vaccinations
Common transmission of Brucellosis to humans is from what species?
Sheep and goats
In what states is Brucellosis more prevalent?
Texas, California, Virginia and Florida
What are the mechanical vectors for Brucellosis?
Contaminated food, water and exretement
Ingestion of bacteria present in large animals in aborted fetuses and uterine discharges
Sexually transmitted fluids
Open wounds, conjunctiva or inhalation
Ingestion of contaminated milk
What is the pathogenesis of Brucellosis?
Brucella are engulfed by neutrophils and are carried in the lymphatic fluid to the lymph nodes, blood and organs
Clinical signs of Brucellosis
Spontaneous abortion, inability to conceive, inflammation of sex organs, death
What are methods of diagnosis of Brucellosis?
Gram stain
Culture
Serum Agglutination and ELISA
Treatment for Brucellosis?
Not attempted. Many recover from disease signs but infection remains. Infected animals are often eliminated.
How can Brucellosis be managed?
Vaccination and testing before breeding
What is the most common cause of acute infectious diarrhea?
Campylobacteriosis
Disease also known as vibriosis and vibrionic abortion
Campylobacteriosis
Disease that produces endotoxins that invade jejunum, ileum and colon as well as hemorrhagic legions
Campylobacteriosis
Disease that causes hepatitis in poultry and abortion in ruminants
Campylobacteriosis
What is the treatment for Campylobacteriosis?
7-28 day antibiotic treatment
Infection found in almost all anaerobic environments, gram positive and endospore forming bacilli
Clostridial infections
Infection associated with botulism, c-diff, and tetanus (uncommon in the US)
Clostridial infections
Disease causing rapidly fatal motor palysis
Botulism
Disease common in chickens causing flaccid paralysis of legs, wings, eyelids and neck
Botulism
Disease with lower cases in cattle causing drooling, inability to urinate, dysphagia and death
Botulism
What species are resistant to Botulism?
Dogs, cats and pigs
Sheep become infected with this disease via eating infected rabbits
Botulism
In horses, this disease causes death, stilted gait, muscular tremors, dysphagia, constipation
Botulism
What species is most sensitive to Cl Tetani?
Horses
What species are most resistant to Cl tetani?
Dogs, cats and birds
How are clostridial infections diagnosed?
ELISA, gram stain, tissue culture, and history
How is clostridium treated?
Antibiotics and antitoxins
No treatment depending on species of clostridium due to ineffectivity based on severity of infection
Disease that causes diamond shaped lesions
Erysipellas
During what seasons is Erysipeloid most prominent?
Summer or early fall
How is Erysipelas transmitted?
Wounds and ingestion of contaminated feces
Disease that produces enzymes that dissect tissues
Erysipelas
How are pigs treated for Erysipelas?
Antiserum and antibiotics
Chronic infections may require culling
What species infected with Erysipelas are treated with Penicillin?
Birds and sheep
Disease also known as malleus?
Glanders
Disease causing SQ nodules, and is a fatal skin and respiratory disease affecting horses, donkeys and mules
Glanders
What is the causative agent of Glanders?
Burkholderia mallei
Disease that produces toxins that interfere with energy production, lysis of cell membranes and cell death
Glanders
What are the three forms of Glanders?
Acute, chronic and latent
How is Glanders diagnosed?
Culture, PCR, ELISA, and Mullein test
Why is treatment of Glanders not recommended?
Potential spread to humans
How is Glanders managed/controlled?
Infected animals should be euthanized. No vaccine exists.
Disease excreted in urine, parturition fluids and contaminated water and soil
Leptrospirosis
Disease seen more during summer and fall, with high incidence in tropical areas
Leptospirosis
What occurs during the acute or early phase of Lepto?
enters the blood stream and multiplies in the kidney - also enter the ceberospinal fluid
What occurs during the subacute or second phase of Lepto?
Blood infection resolves, endotoxin produced leads to decrease red blood cells and tissue injury
How is Lepto diagnosed?
Urinalysis, culture (6 weeks in the dark), agglutination, ELISA, PCR
Treatment for this disease is only efficient if initiated early.
Leptospirosis
Disease also known as “circling disease”
Listeriosis
Disease occuring primarily in newborn infants, elderly patients and immunocompromised people
Listeriosis
Disease that may be present in the intestinal tract of 1-10% of humans
Listeriosis
Causitive agent of listeriosis
Listeria monocytogenes
What is the peak time for listeriosis?
Between February and April
What are the reservoirs for Listeriosis?
soil and intestinal tract
What kind of transmission of listeriosis occurs in ruminants?
Vertical transmission
Disease that binds to epithelial cells of the GI tract, triggers phagocytosis
Listeriosis
What occurs after neurological symptoms of listeriosis?
Death
How can listeriosis be managed?
Feed high quality feed, isolate infected animals
Disease also known as shipping fever in cattle and snuffles in rabbits
Pasteurellosis
Yersinia pestis is the causative agent of what bacterial disease?
Plague
What are the three forms of plague?
Bubonic, Pneumonic, and septicemic
Approximately 50% of cats contract what form of plague?
Bubonic
What can be used to treat plague?
Streptomycin and tetracycline combination
How is the plague diagnosed?
Fluorescent antibody test, aspirate lymph node, PCR
Disease causing food poisoning
Salmonellosis
What are the 3 forms of salmonellosis?
Septicemia, Acute enteritis, chronic enteritis
Primary reservoirs of salmonellosis
Poultry, livestock and reptiles
What diseases are caused by strep?
Scarlet fever, pneumonia, strangles, mastitis
Antibiotic of choice for strep infections
penicillin
Disease also known as deer fly fever or rabbit fever
Tulamemia
Francisella tularensis is the causitive agent of what disease?
Tularemia
Treatment for Tulameria
Streptomycin and tetracycline
Disease also known as Goat bloat fever or Query fever
Q Fever
Disease commonly seen in slaughterhouse workers in the 1940s
Q fever
Coxiella burnetti is the causitive agent of what disease?
Q fever
Q fever is seen worldwide except what country?
New Zealand
How is Q fever diagnosed?
Can not be cultured.
ELISA test
Complement fixation
What is the treatment for Q fever?
Tetracycline
Disease typically infected and spread by hard ticks
RMSF
How is Q fever transmitted?
Inhalation, direct or indirect contact with infected animals or dried excretions (milk or amniotic fluid), ticks
In what disease does pregnancy stimulate the replication of bacteria in reproductive and mammary gland tissues
Q Fever
Disease also known as black measles and spotted fever?
Rocky Mountain Spotted Fever
600-800 cases in humans a year in the US
RMSF
What are the main hosts of RMSF?
Arthropods
Clinical signs of petichia may indicate what bacterial disease?
RMSF
Disease common in dogs 3 years old or younger, most commonly contracted between March and October
RMSF
Dog showing low platelet counts, moderate leukocytosis with a left shift (increase in band neutrophils) may have what disease?
RMSF
Treatment for RMSF
Tetracycline or Doxycycline
Chloremphenicol (pregnant and puppies less than 6 months)
Fungi type that are chemically and genetically similar to animals which makes it challenging to treat
Eukaryotic
How is fungi classified?
Reproduction and presence of hyphae
Type of fungi that are either yeast or mold
Dimorphic
What two types of fungi are animals not generally tolerant?
True pathogens and opportunistic pathogens
Fungi that can infect healthy animals
True pathogens
Fungi that present in low numbers in animals that cause disease when the host environment is altered
Opportunistic
Fungi that cause ringworm
Trichophyton and microsporum
Fungi that cause chrombastomycosis
Fansecaea
Fungal disease that invades body tissues and tends to be dimorphic fungi- blastomyces
Systemic mycoses
Normally harmless fungi that cause disease when host is compromised - candida
Opportunistic fungi
Non contagious fungi respsonsible for tinea crursis (ringworm of groin/jock itch)
Epidermophyton
Nutrient source for dermatophytosis
Keratin
Most common dermatophytosis worldwide (92% in children less than 10)
Tinea pedis
Fungal growth and spore formation within the hairshaft (ex. trichophyton tonsurans and T violaceum)
Endothrix
Fungal growth producing spores on the outside of the hairshaft (microsporins)
Ectothrix
Dermatophytes most commonly affecting cattle
T Verrucousm
Subcutaneous fungal disease also known as rose gardener’s disease
Sporotrichosis
Fungal disease common in intact male cats
Sporotrichosis
Disease commonly seen in north central and south eastern US (including OH) that causes granulomatous nodules in lungs and on skin
North American Blactomycosis
Amphotericin B and ketoconazole are treatment options for which fungal disease?
North American Bastomycosis
Disease also known as Ohio Valley Fever or Darling’s disease
Histoplasmosis
Histoplasmosis is seen everwhere except which continent?
Australia
This disease is benign after inhalation of small amounts but becomes severe overnight
Histoplasmosis
Ketoconazole is used to treat what fungal disease?
Histoplasmosis
Disease also known as Valley Fever, San Joaquin Fever and California Disease
Coccidiodomycosis
Disease that resembles tuberculosis, favors habitats with high carbon and salt content
Coccidiodomycosis
Fluconazole is used to treat what fungal disease?
Coccidiodomycosis