Zoonoses Flashcards
What is zoonoses?
o Diseases that pass between people and animals
o More than 70% of emerging human infectious diseases come from animals
o Examples of new emerging infectious diseases
§ VHF (viral haemorrhagic fevers)
§ Respiratory diseases (MERS)
§ Novel influenza viruses (pH1N1
How do zoonoses transmit?
o Everyday contact with animals – scratches and bites
§ Traditional pets – i.e. dogs and cats
§ Less traditional pets – i.e. reptiles, rodents and chickens
o By-products (faeces/urine) – contaminated soil, litter
o Foodstuffs – carcass processing, milk and milking, raw/undercooked meats
What is the classification of zoonoses?
· The TWO levels of classification are based on:
o Farm/Wild vs Companion
o UK vs Tropical
· Farm/wild animals
o Cattle
o Poultry
o Goats
o Pigs
· Companion animals
o Cats/dogs (ticks, mice/rodents)
o Reptiles/amphibians
o Fish
Summarise campylobacter
o Reservoir = poultry, cattle
o Transmission = contaminated food
§ Often, cross-contamination
o Clinical Presentation:
§ Diarrhoea
§ Bloating
§ Cramps
o Investigations
§ Stool culture
o Management
§ Supportive
Summarise Salmonella
o Reservoir = poultry, reptiles/amphibians
o Transmission:
§ Contaminated food
§ Poor hand hygiene
o Clinical presentation
§ Diarrhoea
§ Vomiting
§ Fever
o Investigations
§ Stool culture
o Management
§ Supportive
§ Ciprofloxacin or Azithromycin
Summarise Bartonella
o Reservoir = kittens>cats
o Transmission:
§ Scratches Bites
§ Licks of open wounds Fleas
o Diseases caused:
§ Cat Scratch Disease
§ Bacillary angiomatosis
Summarise cat scratch disease
§ Presentation
· Macule at site of inoculation Becomes pustular
· Regional adenopathy Systemic symptoms (fever, night sweats, weight loss)
§ Investigations
· Serology
§ Management
· Erythromycin Doxycycline
§ NOTE: this disease can present fairly similarly to other classical clinical presentations such as TB and lymphoma -> always consider Bartonella in a young person with fever, weight loss and night sweats who has been in recent contact with a cat
Summarise Bacilliary Angiomatosis
§ Presentation -> can be fatal
· Skin papules
· Disseminated multi-organ and vasculature involvement
· Leads to bursting of blood vessels in various organs and tissues
§ Investigations
· Histopathology
· Serology
§ Management – wash hands after handling cats, use flea control
· Erythromycin Doxycycline
· Add Rifampicin
Summarise the presentation of toxoplasmosis
o Reservoir = cats, sheep
o Transmission:
§ Infected meat
§ Faecal contamination
o Clinical presentation:
§ Fever + adenopathy
§ Still-birth
§ Progressive visual loss Progressive hearing loss
§ Progressive motor loss Progressive cognitive loss
§ Seizures
§ Neuropathies (immunocompromised)
Summarise the management of toxoplasmosis
o Investigations
§ Serology
§ Sabin Feldman Dye test
o Management
§ Toxoplasmosis PCR +ve in mother, -ve in baby à Spiramycin (3-week course, 2-3g/day)
· I.E. no vertical transmission
· Spiramycin prevents vertical transmission
§ Toxoplasmosis PCR +ve in mother, +ve in baby -> Pyrimethamine + Sulfadiazine
· Treat baby for up to 1 year after delivery (if no TOP)
· Adjunct: Prednisolone
Summarise Brucellosis
o Reservoir = cattle, goats
o Transmission:
§ Unpasteurised milk/cheese Mucosal splash
§ Undercooked meat Aerosolization/inhalation
o Presentation:
§ FLAWS
§ Back pain
§ Orchitis
§ Focal abscesses (psoas, liver, etc.)
o Investigations:
§ 1st: Blood/pus culture (in Castaneda medium)
§ 2nd: Serology
o Management:
§ Doxycycline; and
§ Gentamycin; or rifampicin
Summarise Coxiella
o Reservoir = cattle, goats, (sheep)
o Transmission:
§ Aerosolisation/inhalation of secretions, waste, or milk of infected animals
§ Unpasteurised milk
o Clinical presentation:
§ Fever ‘Flu-like’ illness
§ Pneumonia Hepatitis
§ Endocarditis Focal abscesses (para-vertebral/discitis, etc.)
o Investigations:
§ Serology
o Management:
§ Doxycycline
§ (Hydroxychloroquine)
Summarise Rabies
o Reservoir = dogs, cats, bats
o Transmission:
§ Bites, scratches
§ Contact with infected fluid
o Presentation:
§ Seizures Excessive salivation Fever
§ Agitation Confusion Headache
o Investigations:
§ Serology Brain biopsy
§ (USA saliva PCR)
o Management:
§ Immunoglobulin (only given if direct exposure to saliva likely and no pre-exposure to vaccine)
§ Vaccine
Summarise rat bite fever
o Reservoir = rats (Agents: Streptobacillus moniliformis or Spirillum minus)
o Transmission:
§ Bites
§ Contact with infected urine or droppings
o Presentation (comes on 2-10 days after bite):
§ 1st: fevers, polyarthralgia, maculopapular à purpuric rash
§ 2nd: endocarditis
o Investigations Looks like septic arthritis
§ Joint fluid microscopy/culture
§ Blood culture
o Management
§ Penicillin
Summarise Hantavirus Pulmonary syndrome
o Reservoirs:
§ Deer mouse -> Sin Nombre virus
§ White-footed mouse -> Sin Nombre virus
§ Cotton rat -> Black canal virus
§ Rice rat -> Bayou virus
o Transmission
§ Contact with infected urine or droppings
§ Aerosolisation
o Clinical presentation:
§ Fever Myalgia ‘Flu-like’ illness
§ Respiratory failure (USA) Bleeding (SE Asia) Renal failure (SE Asia)
o Investigations
§ Serology PCR
o Management
§ Supportiv
