Zoonosis Flashcards

1
Q

What is zoonosis?
* By definition zoonosis involves at least ___ hosts and a ______.
* The hosts include:
1. ___________ and
2. one of __________ animal species

A

two, pathogen, humans, vertebrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Of pathogens affecting humans,
60% are ?

A

animal-borne (zoonotic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Globally, 2.5 billion cases related to zoonotic infections
are recorded, resulting in 2.7 million deaths each year

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

80% of the source of zoonosis are _____________

A

mammals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why are most zoonosis (99%) from domestic animals?

A

96% of global mammal biomass is human & livestock.
We are more genticlaly related to mammals than fish and amphibians, so this is logical.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How many transmitted by rodents? Bats?

A

85, 27

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Classification of zoonosis based on?

A
  1. Etiological agent
  2. Number of hosts involved
  3. Direction of transmission
  4. Route of transmission (air/breath, contact, food, soil, vector, water = 7 Fs)
  5. Scale of the disease, social panic, & policy-makers priority (pandemic, neglected, or bioterrorism i. e. CDC List A, B & C)
  6. Government consensus/priority for One-Health approach
  7. Ecological source for its transmission cycle (aquatic, sylvatic, domestic)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Zoonosis
classification based
on etiological agents

A
  1. Prion
  2. Virus
  3. Bacteria
  4. Fungi
  5. Protozoa
  6. Cestodes
  7. Trematodes
  8. Nematodes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Classification of zoonosis based on direction of transmission

A
  1. Anthropozoonoses (animals are main host): animal-to-human
     Viruses: Rabies, avian or swine influena, rift valley fever,
     Bacteria: anthrax, brucella, leptospira, plague, lyme, tularemia, psittachosis
     Parasites: hydatidosis
  2. Zooanthropozonoses (humans are main host): human-to-animal
     Ameoba, diphtheria, human
    M. tuberculosis from human to parrot, cat or Mokey
  3. Amphixenoses (maintained by both): migrate either direction between animal and humans equally
     non-host specific
    Salmonella, Staphylococcus, streptococcus,
    E.coli
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Classification of zoonosis based on number of host
species (maintenance cycles) required for transmission

A

e.g. Rabies –> in absence of humans, rabies can maintain in env?, same with anthrax.
2. one is serving as final host, the other is serving as an intermediate host where larvae grow. Cattle = intermediate?
3. Invertebrate arthropod; if sit in vertebrate they will die in vertebrate.
4. Need inanimate such as soil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which pathogens have a high impact on global level?

A

Plague
Cholera
inflouenza virus
Coronavirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the Three CDC categories of bioterrorism agents:?

A
  1. List A: 3 bacteria, 3 viruses, & 1 toxin
  2. List B: 11 bacteria, 3 viruses, & 3 toxins
  3. List C: 4 newly emerging viruses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

List A - CDC bioterrorism agents?

A

Causing devastating impact on public health and panic in society, leading to social disruption. This list includes:
1. Anthrax.
- Previously used by terrorists in 2001.
- Cause respiratory, gastrointestinal, or neurological symptoms

  1. Plague:
    - Previously used by terrorists.
    - Respiratory and gastrointestinal symptoms
  2. Tularemia:
    - Previously used by terrorists.
    - Respiratory symptoms
  3. Botulism toxin
  4. Viral hemorrhagic fevers
    - Not used previously by terrorists.
    - Neurological and respiratory symptoms
    a. Filovirus: Ebola and Murburg
    b. Bunyavirus: Crimean-Congo virus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Most bioterrorism
agents target

A
  1. respiratory systems
  2. Nervous system
  3. Cardiovascular system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

List B

A
  1. Melioidosis (Burkholderia pseudomallei)
  2. Glanders (Burkholderia mallei)
  3. Brucellosis (Brucella species)
  4. Psittacosis (Chlamydia psittaci)
  5. Q fever (Coxiella burnetii)
  6. Typhus fever (Rickettsia prowazekii)
  7. Viral encephalitis [alphaviruses (e.g., eastern and western equine encephalitis)]
    5-7 = vector borne
  8. Toxin:
    1. Ricin
    2. Staph. aureus enterotoxin B,
    3. Epsilon toxin of Clostridium perfringens
  9. Food threats:
    1. Salmonella
    2. Shigella
    3. E.coli O157
  10. Water bioterrorism threats:
    1. Vibrio cholera
    2. Cryptosporidium
      8-10 = food and water borne
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

List C

A

We do not know much about them, so they are emerging pathogens. The US government files them under “could be used as bio”
Nipah virus –> Pig Rinderpest, comes from bats
Hantavirus
West Nile Virus (Flavivirus)
Japanese Encephalitis

Observe any morbidity or mortality in these animals, affect public unless you stop the spread. These would be an early warning or indicator that something is wrong.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Classification of zoonosis based
on government priority
Neglected zoonosis diseases become an emerging/re-emerging disease; hence, some of
the neglected zoonosis are now priority for control in a One-Health approach in the USA
1. 27 Neglected (forgotten) zoonosis diseases
2. 8 Zoonotic pathogens of One-Health priority

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the4 27 neglected zoonoses reported to the CDC in the USA?

A

Brucella, psitaccosi, trich, lepto, etc (relisren)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

U.S. Govt changed their mind about the 27 neglected, and picked the top 8 zoonosis of most concern in the USA with a One-Health significance

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Classification of zoonosis based on
animal species & ecological source for
transmission cycle of zoonosis

A
  1. Aquatic
  2. Domestic/urban
  3. Sylvatic (wildlife)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Fish-borne zoonotic diseases affect mainly fishermen,
aquaculture workers and seafood consumers

A

Enteric virus = norovirus, Hep A, sapo virius?
Enteric bacteria = enterobateriace, salmonella, e.coli, shigella, vibrio, campylo
Enteric protozoa = giard, crypto
Universally present in vertebrates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

List the Fish-borne zoonotic bacterial diseases

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q
A

Hand of a farmer with necrotic fasciitis caused by
a Vibrio vulnificus outbreak at his eel farm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q
A

Fish handlers at risk
E. rhusiopathiae
has a characteristic
purplish, swollen, painful,
hardened rash known as
erysipeloid…..but Do NOT
produce PUS!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Man with a tender nodule on the dorsum of his right hand (‘swimmer granuloma’) caused by Mycobacterium marinum Also causes pneumonia?
26
Diphyllobothrium is the ?
Longest tapeworm in the human intestine. 10m, releases 1 million eggs each day and affects 20 million people globally. We can get this from eating fish. 1. Cestodes:  Diphyllobothrium is the most important fish-borne zoonosis caused by a cestode (tapeworm) parasite, affecting 20 million people globally  The adult tape worm can reach >10 m in length, with more than 3,000 proglottids.  Immature eggs are discharged from the proglottids (up to 1,000,000 eggs per day per worm)
27
Fishborne zoonotic parasites of humans?
1. cestodes - Diphyllobothrium 2. Nematodes: Anisakis 3. 3. Trematodes: >45 million persons globally are infected with fish-borne zoonotic trematodes. The life cycle of trematodes depends on three types of hosts; 1. primary snail hosts, 2. secondary fish hosts, 3. definitive hosts like humans, dogs or fish-eating birds Opisthorchis & Clonorchis liver flukes = LIVER CANCER
28
 Reptiles are a natural reservoir with very high prevalence of ____________.  Reptiles have relatively high contribution to human infections, especially in _______.
Salmonella, children
29
Mosquito-borne vial zoonosis
1. Zika 2. EEE 3. Western Equine Encephalitis 4. West Nile Virus 2-4 --> bite from Culex mosquito --> brain eating viruses
30
Bacte4rial zoonosis
. Salmonella 2. E. coli 3. Campylobacter 4. Aeromonas 5. Rickettsia sp.:  bite of mites or ticks from snake, lizard, tortoises 6. Anaplasma phagocytophilum:  bite of ticks from infected lizard 7. Borellia:  bite of ticks from infected lizard, tortoises, snake 8. Coxiella:  bite of ticks from infected lizard, snake 9. Ehrlichia:  bite of ticks from infected lizard
31
Protozoa zoonosis
1. Cryptosporidium 2. Giardia 3. Leishmania:  bite of sand flies from lizards
32
Zoonotic worms that come from birds?
33
Avian-borne zoonosis
 Avian influenza  Coronavirus (SARS) * Chikungunya  Japanese encephalitis virus  Eastern equine encephalitis virus * West Nile virus  New Castle disease  etc
34
Avian-borne bacterial zoonosis
 Salmonella  Campylobacter  E. coli  Pasteurella multocida  Yersinia enterocolitica  Mycobacterium avium --> TB  Psittacosis  etc Particularly in egg - why? Fecal material on the outside of the egg.
35
Contact with nasal secretion:  Chlamydia psittaci Transmit psittacosis
36
Pasteurella multocida
37
Fungus from birds
1. Cryptococcus neoformans:  contact with feces of infected pigeons and starlings 2. Histoplasma capsulatum:  breath of infected pigeon or bat feces
38
Protozoa from birds?
1. Cryptosporidium:  contact with feces of infected birds or foodborne by ingestion under cooked meat and eggs
39
Pet-borne zoonotic parasites
toxocara is a roundworm, nematode. Larave penetrate our skin and cause cutaneous larva migrans
40
Pet-borne vector-borne zoonotic disease
Bite of dogs transmits 90% of rabies
41
Pet-borne zoonosis transmission routes to humans
42
Rabies, echino, barto --> severe if happens
43
Important livestock & poultry-borne zoonosis of humans
Bovine TB, chlamydia, listeria, Q fever --> humans Pig trich, swine, Hep E, etc --> humans Horses:
44
How many serotypes of Salmonella exist?
2500 different serotypes of Salmonella have been recognized
45
Salmonella bacteria are widespread in the: 1. environment and 2. Animals` gastrointestinal tract:  fish  amphibians  reptiles,  birds,  mammals
46
What is the role of wildlife, rodents, bats, wild birds, their movements & their contacts with humans (e. g. bush meat) in zoonosis
47
Avian influenza Pandemic in 2004. Miratory birds brought this influenza to poultry industry in asia and then this came to the public. resulting in 20 billion USD losses. Bovine TB in UK, badger are a reservoir --> cattle industry --> humans; killed all of the cows and the badgers costing 15 billion Ebola come from monkey, chimp, bat --> humans MERS , Nipah, corona
48
Rodent viruses
49
Rodent bacteria
50
Zoonosis classification based on transmission routes AKA 7 F's
51
Animal bites/scratches/licks transmit zoonosis Reducing the risk of pet-associated zoonotic infections 1. Rabies – causes agitation, anxiety, confusion, hallucination, and hydrophobia 2. Pasteurella multocida – cause wound infection of soft tissues and gangrene 3. Bartonella henselae - a facultative intracellular microbe of red blood cells. In the USA, bartenellosis is more common in under the age of 20
52
Zoonosis transmitted by damaged skin?
 Anthrax  Erysipelothryx  Pasteurella
53
Route of transmission of zoonotic pathogens
1. Direct contact & 2. Food-borne  Both routes are the two major transmission highways of zoonosis from animals to humans  A single pathogen uses multiple routes
54
Zoonotic disease control
55
Control of zoonotic diseases
56
. Eliminate zoonosis by eliminating its source
– mass culling/killing then burning animals * Culling reservoir animals for zoonosis to control at its source 1. Culling 50,000 goats in The Netherlands – to control Q fever 2. Culling 35,000 badgers in UK – to control bovine TB 3. Culling over 4 million cattle in UK – to control BSE (‘mad cow’ disease) 4. Killed and burnt 6.5 million food animals in UK - to control FMD in 2001 (technically a zoonosis but difficult for us to get so he said it isn;t)
57
Rather mass culling/killing, selectively remove the infected individual animals * Removal of infected individual can be accomplished in three ways, namely 1. Test and slaughter/cull infected animals – successfully eliminated brucellosis, tuberculosis, glanders, dourine 2. Test, isolate, and treat infected individual animals by drug – 3. Isolate the entire herd (also called quarantine) that may have been exposed to a source of infection for the longest incubation period of the diseases in question – Trepanosome --> transmitted via sex in equids
58
59
Rather than mass culling/killing or mass medication, mass vaccination of animals against zoonosis. How?
Q fever --> 20 km Mycobacterium --> 10 km
60
How much proportion of animals in the population be vaccinated to control zoonosis?
61
Licensed animal vaccines have double function: immunization of animals reduces zoonotic disease transmission to human
62
Vaccination or medication of humans to protect them from zoonosis
63
How to 5. Break/control the transmission routes of zoonosis
64
Minimize unnecessary intensive contact with animals whose health condition is not tested  Children  Pregnant  elderly  immune-compromised humans