Zoonoses

Question 1

What is zoonosis?

Answer 1

An infection that can naturally pass between living animals and humans where the source of the disease is the vertebrate animal

Question 2

What is the epidemiology of zoonoses?

Answer 2

61% of pathogens are zoonotic,

Question 3

What are the clinical features of: brucellosis, Lyme disease, leptospirosis, rabies?

Answer 3

Brucellosis
Used to be an occupational hazard of farmers, vets, slaughterhouse workers etc
- acute: 1-3wk, high fever, weakness, headaches, drenching sweats, splenomegaly
- subacute: >1m, fever and joint pains
- chronic: months to years, flu like symptoms, malaise, depression, endocarditis, chronic arthritis, epididymoorchiditis, splenomegaly.
- subclinical: most common

Leptospirosis (L hardjo most common, from cattle)
Fever, meningism.

Lyme disease, vector is a tick
- erythema migrans, acrodermatitis chronica atroficans, lymphocytoma, neuroborreliosis (triad of facial nerve palsy, radicular pain, lymphocytic meningitis)

Rabies
- acute encephalitis eg malaise, headache, fever > mania, lethargy, co,a > over production of saliva, tears > unable to swallow and hydrophobia > death by respiratory failure

Question 4

What is the long term sequelae of Lyme disease?

Answer 4

X

Question 5

How do you approach diagnosis and treatment of common zoonoses?

Answer 5

Brucellosis
- doxycycline for 2-3m + rifampicin or + IM gentamicin for 1st week

Leptospirosis

• culture
• doxycycline for mild, IV penicillin for severe, prompt dialysis, mechanical ventilation

Lyme disease

• EM is clinical, serology titres from synovial fluid, PCR, CSF serology, FBC, ELISA
• oral doxycycline or amoxicillin or IV ceftriaxone

Rabies

• PCR of saliva or CSF
• post exposure prophylaxis, human rabies immunoglobulin