Zoonoses Flashcards
1
Q
What is the WHO definition of a zoonosis?
A
A disease/infection which is transmitted naturally between vertebrate animals and humans
2
Q
List 5 zoonoses transmitted by mice
A
Hantan viruses (fleas) Lyme borreliosis Ehrlichia Bartonella Lymphocytic choriomeningitis
3
Q
List 7 zoonoses transmitted by rats
A
Rabies Leptospirosis Lassa fever Hantan viruses Plague Pasteruellosis Haverhill fever (rat bite)
4
Q
List 7 zoonoses transmitted by cats
A
Bartonellosis (cat scratch) Leptospirosis Q-fever Toxoplasmosis Rabies Ringworm Toxocariasis
5
Q
List 8 zoonoses transmitted by dogs
A
Hydatid disease Leptospirosis Brucellosis Q-fever Rabies MRSA Ringworm Toxocariasis
6
Q
List 9 zoonoses transmitted by small ruminants (sheep and goats)
A
Anthrax Brucellosis Q-fever Cryptosporidiosis Enzootic abortion Louping ill Orff virus Rift valley fever Toxoplasmosis
7
Q
List 9 zoonoses transmitted by cattle
A
Anthrax Leptospiriosis Brucella Bovine TB Anaplasmosis Toxoplasmosis E. coli 0157 Rift valley fever Ringworm
8
Q
List 8 zoonoses transmitted by swine
A
Brucellosis Leptospirosis Erysipeloid Cysticerosis Trichinella HEV Influenza A Streptococcal sepsis
9
Q
List 6 zoonoses transmitted by birds
A
Psitticosis Influenza Cryptococcus Influenza A Salmonella (poultry) West Nile fever (poultry)
10
Q
List 7 water-sports associated zoonoses
A
Leptospirosis HAV Giardia Toxoplasmosis Mycobacterium marinum/ulcerans Burkholderia pseudomallei E. coli
11
Q
List 4 water-borne zoonoses
A
Campylobacter
Salmonella
E. coli toxin (VTEC 0157)
Cryptosporidiosis
12
Q
List 7 food-associated zoonoses
A
Listeria (cow-cheese-human) Taenia Cysticercosis Toxoplasmosis Trichinellosis Yersiniosis Giardia
13
Q
Brucella - microscopic features
A
Gram-negative Aerobic Facultatively intracellular Endemic world wide Small Nonencapsulated Flagellated Coccobacilli
14
Q
What is the name of the disease caused by brucella?
A
Brucellosis
15
Q
Which 4 animals are associated with brucellosis?
A
Farm animals
Dogs
Cattle
Small ruminants
Swine
16
Q
What are the 3 modes of transmission of brucellosis?
A
Inhalation
Skin contact
Mucus membrane contact
Ingestion
17
Q
How is brucellosis contracted?
A
Consumption of contaminated food (untreated milk/dairy)
Animal contact
Environmental contamination
Laboratory acquired
18
Q
List 6 symptoms of brucellosis
A
Undulant fever (peaks in evening, normal by morning) Malaise Rigors Sweating Myalgia/arthralgia Tiredness
19
Q
What is the incubation period for brucellosis?
A
3-4 weeks
20
Q
List 3 potential complications of brucellosis
A
Endocarditis
Osteomyelitis
Meningoencephalitis
21
Q
List 6 signs of brucellosis
A
Arthritis Spinal tenderness Lymphadenopathy Splenomegaly Hepatomegaly Epididymo-orchitis
22
Q
List 4 rare signs of brucellosis
A
Jaundice
CNS abnormalities
Cardiac murmur
Penumonia
23
Q
What investigations are performed if brucellosis suspected, and what are the likely results?
A
Serology
- Anti-O polysaccharide antibody (titres >1:160)
FBC
- WCC normal
- Leukocytosis rare
- Significant number of pts neutropaenic
24
Q
What is the treatment for brucellosis?
A
4-6 weeks of tetracycline or doxycycline AND stretomycin
OR
8 weeks of doxycycline AND rifampicin
25
What is the name of the pathogen that causes rabies?
Rhabdovirus
26
What are the 2 most common animal vectors of rabies?
Dogs and bats
27
How long does rhabdovirus take to migrate to the CNS?
Months - years
28
Without treatment, how does rabies progress?
Fatal encephalitis - death usually occurs within 2-10 days, survival rare once symptoms have presented
29
What is the name of the cerebral inclusions seen in brain samples that are pathognomonic for rabies?
Negri bodies
30
Give 3 features of the rabies prodrome
Fever
Headache
Sore throat
31
Which test can be used antemortem to detect the rabies antigen in brain tissue?
Indirect Fluorescent Antibody Test (IFA)
32
Other than IFA, name 2 other tests that can be used to diagnose rabies
Serological neutralisation test
| ELISA, for specific IgM
33
What is the treatment for rabies?
Post exposure IgG
Recent experimental treatment (at symptomatic presentation): Milwaukee protocol. Successfully saved first patient in 2004. Involves induced coma, ketamine and antivirals.
34
What is the name of the bacteria responsible for bubonic plague?
Yersinia pestis
35
Yersinia pestis - microscopic features
Gram-negative
Lactose fermenter
Rod-shaped coccobacillus
Facultative anaerobe
36
Which animals are a source of yersinia pestis and how is it transmitted?
Rats
| Transmitted by fleas
37
How is plague diagnosed?
PCR
38
How is bubonic plague contracted and how does it present?
Flea bites human
| Presents with swollen lymph nodes (bubos) and dry gangrene
39
How does pulmonary plague differ from bubonic?
Spread person-person (rather than rat-flea-person)
| This kind of plague seen during (relatively) more recent epidemics
40
What is the treatment for plague?
Streptomycin
Doxycycline
Gentamicin
Chloramphenicol (in meningitis)
41
Leptospira interrogans - microscopic features
Gram -ve
Spirochaete (spiral shaped)
Obligate aerobic
Motile
42
What is the name of the disease caused by Leptospira interrogans?
Leptospirosis
43
How is leptospirosis transmitted?
L. interrogans excreted in dog/rat urine
Penetrates broken skin when swimming in contaminated water
44
List 5 animal sources of leptospirosis
```
Rats
Cats
Dogs
Cattle
Swine
```
45
What is the incubation period for leptospirosis?
10-14 days
46
How does leptospirosis present?
```
High spiking fever
Headache
Conjunctival haemorrhages
Jaundice
Malaise
Myalgia
Meningism
Carditis
Renal failure
Haemolytic anaemia
```
47
What is the treatment for leptospirosis?
Amoxicillin, erythromycin, doxycycline or ampicillin
48
What is the name of the bacteria that causes anthrax?
Bacillus anthracis
49
Bacillus anthracis - microscopic features
```
Obligate pathogen
Gram-positive
Endospore-forming
Rod-shaped
Can be grown in an ordinary nutrient medium under aerobic or anaerobic conditions
```
50
List 2 animal sources of anthrax
```
Cattle
Small ruminants (sheep, goats)
```
51
How does cutaneous anthrax present?
Small black lesions with a rim of oedema
52
How does pulmonary anthrax present?
Massive lymphadenopathy
Mediastinal haemorrhage
Pleural effusion
Respiratory failure
53
What is another name for pulmonary anthrax?
Woolsorter's disease
54
What is another name for Lyme disease?
Lyme borreliosis
55
What is the name of the bacterium that cause Lyme disease?
Borrelia burgdoferi (and other Borrelia spp)
56
Borrelia burgdoferi - microscopic features
```
Spirochaete
Diderm (double-membrane) therefore neither gram positive nor negative
Flat wave shape
Anaerobic
Motile
Flagellated
```
57
How is Lyme disease transmitted?
Arthropod-borne, transmitted through tick (ixodes) bite. Ticks also transmit to other vertebrates eg mice
58
What are the symptoms of early localised Lyme disease?
Cyclical fevers
Non-specific flu-like symptoms
Erythema chronicum migrans (ECM) - "Bullseye rash"
59
How does early disseminated Lyme disease present?
```
Malaise
Lymphadenopathy
Hepatitis
Carditis
Arthritis
```
60
How does late persistent Lyme disease present?
Arthritis
Focal neuropathy
Neuropsychiatric disturbance
Acrodermatitis chronic atrophicans (ACA)
61
How is Lyme disease diagnosed?
Biopsy of the edge of the bullseye rash
| ELISA for Lyme antibodies
62
What is the treatment for Lyme disease?
Doxycycline for 2-3 weeks (alternatively amoxicillin, cephalosporins)
If CNS issues: IV ceftriaxone for 2-4 weeks
63
What is a potential consequence following treatment for Lyme disease?
ME type symptoms
64
Which bacterium causes Q fever?
Coxiella burnetii
65
Coxiella burnetii - microscopic features
Obligate intracellular
Gram-negative
Highly resistant to environmental stresses
Biphasic developmental cycle
66
What is the treatment for Q fever?
Doxycycline
67
Which other respiratory disease might Q fever be mistaken for?
Atypical pneumonia
68
How does Q fever present?
```
Symptoms begin 2-5 weeks post infection
Fever
Dry cough
Fatigue
Pleural effusion
Diarrhoea
NO rash
```
69
Does Q fever cause a rash?
No
70
List 4 animal sources of Q fever
Cattle
Sheep
Dogs
Cats
71
Which pathogens cause Leishmaniosis?
Protozoan parasites of the genus Leishmania
72
How is the Leishmania parasite transmitted?
Via the bite of certain types of sandflies (South and Central America, Middle East)
73
Which 2 Leishmania species cause cutaneous Leishmaniosis?
L. major
| L. tropica
74
How does cutaneous Leishmaniosis present?
Skin ulcer at site of bite (due to multiplication of dermal macrophages)
Heals after 1 year leaving depigmented scar
May be single/multiple painless nodules which grow and ulcerate
75
What type of hypersensitivity reaction is cutaneous Leishmaniosis?
Type IV
76
How many types of Leishmaniosis exist, and what are they?
4 types
Cutaneous
Diffuse cutaneous
Muco-cutaneous
Visceral
77
Which patients are more likely to get diffuse cutaneous Leishmaniosis?
Immunodeficient
78
How does diffuse cutaneous Leishmoniosis present?
Nodular skin lesions that do NOT ulcerate
Lots of nodules, esp on nose
Skin test -ve (due to immunodeficiency)
79
Which Leishmania species causes muco-cutaneous Leishmaniosis?
L. braziliensis
80
How does muco-cutaneous leishmaniosis present?
Dermal ulcer same as cutaneous leishmaniosis
| Months/years later: ulcers in mucous membranes of nose and mouth
81
What is visceral leishmaniosis also known as?
Kala Azar
Black fever
Dumdum fever
82
Which 2 species of leishmania cause visceral leishmaniosis?
L. donovani
L. infantum
L. chagasi (South America)
83
Which patients are more likely to get visceral leishmaniosis?
Young, malnourished children
84
How does visceral leishmaniosis present?
Abdo discomfort
Distension
Anorexia
Weight loss
85
What specific pathology is caused by L. donovani?
Invasion of the reticuloendothelial system
Causes hepatosplenomegaly and BM invasion
Later results in disfiguring dermal disease, post kala-azar dermal leishmaniasis (PKDL)
