Microbio: Zoonoses

Question 1

What are zoonoses?

Answer 1

Infections which are transmitted naturally between vertebrate animals and humans”

Question 2

What organism causes Rabies and what is the vector?

Answer 2

Rhabdovirus, from dogs/bats

Question 3

What are the features of rabies infection?

Answer 3

Fatal encephalitis, hypersalivation (MAIN), hydrophobia

Negri bodies = histological findings on biopsy in neurons (MAIN)

Mx = Rabies IgG post-exposure (passive vaccination)

Question 4

What organism causes Lyme disease and what is the vector?

Answer 4

Borellia burgoferi, from Ixodes tick

Question 5

What the RFs for Lyme disease and main cllinical features?

Answer 5

RFs = Walking /camping, deer

Flu-like symptoms; late neurological symptoms

Erythema chronicum migrans (bullseye rash) - MAIN

Question 6

What organism causes Leptospirosis and what is the vector?

Answer 6

Leptospira interrogans in dog/rat urine

Question 7

What are the RFs for leptospirosis + features?

Answer 7

RF = Swimming

Conjunctival haemorrhages (MAIN), jaundice, spiking fever

Question 8

What organism causes Q fever and what is the vector?

Answer 8

Coxiella burnetii, from cattle/sheep

Question 9

What are the features of Q fever?

Answer 9

Atypical pneumonia symptoms: fever, dry cough, pleural effusion

Question 10

A man presents with flu-like symptoms and a bulls-eye rash. He mentions that he enjoys hiking and camping. What is the most likely cause of his symptoms?

a) Lyme disease
b) Rabies
c) Q-fever
d) Leptospirosis
e) Influenza

Answer 10

a) Lyme disease

Question 11

Which histological finding in neurons is pathognomonic of rabies infection?

a) Libman-Sacks immune complexes
b) Caeseating granulomas
c) Negri bodies
d) Kimmelstiel-Wilson nodules
e) Apple green birefringence

Answer 11

c) Negri bodies

a) Libman-Sacks immune complexes -> found in endocarditis due to SLE
b) Caeseating granulomas
d) Kimmelstiel-Wilson nodules -> diabetic nephropathy
e) Apple green birefringence -> amyloidosis