Zoonoses

Question 1

Definition

Answer 1

Diseases and infections which are transmitted naturally between vertebrate animals and man

Question 2

Animals that transmit zoonoses

Answer 2

Mice
Rats
Cats
Dogs
Small ruminants
Cattle
Swine
Birds
Water sports assoc
Water-borne
Food-Assoc

Question 3

Gram -ve aerobic bacilli (facultative intracellular)
Endemic worldwide
Transmitted by inhalation, skin or mucus membrane contact
Consumption of contaminated food (untreated milk/dairy) animal contact or environmental contamination
Includes laboratory acquired

Answer 3

Brucellosis

Question 4

Symptoms of Brucellosis

Answer 4

Fever - classically undulant (peak evening normal by morning), malaise, rigors, sweating, myalgia/arthralgia, tiredness, (incubation 3-4/52)

Question 5

Complications of brucellosis

Answer 5

Endocarditis
Osteomyelitis
Occasionally Meningoencephalitis

Question 6

Signs of brucellosis

Answer 6

Arthritis, spinal tenderness, lymphadenopathy, splenomegaly, hepatomegaly, epididymo-orchitis
Rarely - Jaundice, CNS abnormalities, cardiac murmur, pneumonia

Question 7

Ix of Brucellosis

Answer 7

Serology - anti-O-polysccharide antibody. (Titres >1:160)
WCC usually normal
Leucocytosis rare
Significant number of pts neutropaenic

Question 8

Treatment for Brucellosis

Answer 8

4-6 weeks Tetracycline or Doxycycline combined with streptomycin
Or PO Doxycycline + rifampicin 8/52

Question 9

Rhabdovirus affecting warm blooded animals; dogs and bats most common
Migrates to CBS (mths/yrs) - fatal encephalitis - Negri bodies = pathognomic
Prodrom - fever, headache, sore throat - acute encephalitis (hyperactive state)

Answer 9

Rabies

Question 10

Ix and serology for Rabies

Answer 10

IFA for rabies antigen in brain tissue

Neutralisation tests/ ELISA for specific IgM

Question 11

Treatment for rabies

Answer 11

Rabies IgG Post exposure

Question 12

Gram -ve lactose fermenter. In rats, transmitted by fleas.

Answer 12

Yersinia pestis
Plague
Diagnosis - PCR

Question 13

Flea bites human
Swollen LN
Dry gangrene

Answer 13

Bubonic plague

Question 14

Usually seen during epidemics

Person-person spread

Answer 14

Pulmonary plague

Question 15

Treatment of plague

Answer 15

Streptomycin, Doxycyclin, Gentamicin, Chloramphenicol (in meningitis)

Question 16

Gram -ve
Obligate, aerobic, motile spirochaetes
Excreted in dog/rat urine
Penetrates broken skin/swimming in contaminated water
Incubation (10-14 days)

Answer 16

Leptospirosis

Question 17

Symptoms of leptospirosis

Answer 17

High spiking temp/headache/conjunctival haemorrhages/jaundice, malaise, myalgia, meningism, carditis, renal failure, haemolytic anaemia

Question 18

Treatment of leptospirosis

Answer 18

Amoxicillin, erythromycin, doxycycline or ampicillin

Question 19

Painless round black lesions + rim of oedema

Answer 19

Cutaneous Anthrax

Bacillus anthracis

Question 20

Massive lymphadenopathy + mediastinal haemorrhage, pleural effusion and resp failure

Answer 20

Pulmonary Anthrax (Woolsorters disease)
Bacillus anthracis

Question 21

Treatm,ent for anthrax

Answer 21

Ciprofloxacin

Doxycycline

Question 22

Arthropod borne spirochaete

Answer 22

Borrelia burgodoferi (spirochaete)
Lyme disease

Question 23

Stages and symptoms of Lyme disease

Answer 23

Early localised - cyclical fevers, non-specific flu-like symptoms, erythema chronicum migrans (Bullseye rash)
Early disseminated - Malaise, lymphadenopathy, hepatitis, caraditis, arthritis
Late persistent - Arthritis, focal neurology, neuropsychiatric disturbance, acrodermatitis chronic atrophicans

Question 24

Diagnosis of Lyme disease

Answer 24

Biopsy edge of ECM

ELISA for Lyme Abs

Question 25

Treatment of Lyme disease

Answer 25

Doxycycline 2-3 weeks (also amoxicillin, cephalosporins) CNS issues - IV ceftriaxone 2-4 weeks Post Rx few get ME type symptoms

Question 26

Atypical pneumonia from cattle or sheep | 2-5 weeks post-infection - fever, dry cough, fatigue, pleural effusion, diarrhoea - No rash

Answer 26

Coxiella burnetii Q Fever Rx - doxycycline

Question 27

Transmitted through sand fly bite (South and Central America and Middle East) Skin ulcer at site - multiply in dermal macrophages Heals after 1 year leaving depigmented scar Single or multiple painful nodules - grow and ulcerate Type IV reaction

Answer 27

Cutaneous Leishmania L major L tropica

Question 28

Pts with immunodeficiency Nodular skin lesions arise but do not ulcerate Lots of nodules esp. nose Skin teset -ve as immunodeficient

Answer 28

Diffuse cutaneous Leishmania

Question 29

Dermal ulcer same as cutaneous Months to years later Ulcers in mucous membranes of nose and mouth

Answer 29

Muco cutaneous Leishmania

Question 30

Young malnourished child | Abdo discomfort + distension, anorexia, weight loss

Answer 30

Visceral Leishmania = Kala Azar | L donovani, L Infantum L chagasi (S America)

Question 31

Invasion of reticuloendothelial system - hepatosplenomegaly, BM invasion Later disfiguring dermal disease (PKLD)

Answer 31

Leishmania donovani