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
Summarise viral haemorrhagic fever
o Reservoirs:
§ Ebola (bats) Lassa (rats)
§ Marburg (bats) CCHF (ticks)
o Transmission:
§ Contact with fluids of infected
o Clinical presentation:
§ Fever Myalgia
§ ‘Flu-like’ illness Bleeding
o Investigations
§ Serology PCR
o Management -> supportive
What do you need to ask and investigate in zoonoses?
· Travel history is also very important – specify exactly where they have been
o Continent, country, region, town/village
o Ask what kind of accommodation they stayed in (i.e. 5* or 1* hotels)
o Ask about the types of activities they did (i.e. trekking in caves, sex tourism, etc.)
· Investigations:
o Culture
§ Bloods Pus
§ CSF Stool
o Serology (targeted or save)
o PCR
A 35 yr old patient presents with abdominal cramps and diarrhoea after a BBQ, what is mostly likely the cause?
Beef Pork Chicken Unpasteurised cheese Playing with the tortoise
Chicken
A 35 year old patient presents with fever after a bat bite. What potential infection would they get?
Rabies
A 35 year old is suspected of having brucella of their right psoas after drinking unpasteurised goats milk- what is the first line investigation to obtain?
Blood culture
A 35 year old patient presents with a 38.8 degree fever after returning from 3 months in Rwanda, when they co-habited in a hut with a family and their livestock. How should the patient be managed?
Admit to Bay Transfer to HCID in Royal Free Admit to side room Discharge Discharge to return to ID clinic in 3 days
Admit to side room
