Zoonosis

Question 1

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

Answer 1

two, pathogen, humans, vertebrate

Question 2

Of pathogens affecting humans,
60% are ?

Answer 2

animal-borne (zoonotic)

Question 3

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

Question 4

80% of the source of zoonosis are _____________

Answer 4

mammals

Question 5

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

Answer 5

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

Question 6

How many transmitted by rodents? Bats?

Answer 6

85, 27

Question 7

Classification of zoonosis based on?

Answer 7

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)

Question 8

Zoonosis
classification based
on etiological agents

Answer 8

1. Prion
2. Virus
3. Bacteria
4. Fungi
5. Protozoa
6. Cestodes
7. Trematodes
8. Nematodes

Question 9

Classification of zoonosis based on direction of transmission

Answer 9

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

Question 10

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

Answer 10

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

Question 11

Which pathogens have a high impact on global level?

Answer 11

Plague
Cholera
inflouenza virus
Coronavirus

Question 12

What are the Three CDC categories of bioterrorism agents:?

Answer 12

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

Question 13

List A - CDC bioterrorism agents?

Answer 13

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

2. Plague:
   - Previously used by terrorists.
   - Respiratory and gastrointestinal symptoms
3. Tularemia:
   - Previously used by terrorists.
   - Respiratory symptoms
4. Botulism toxin
5. Viral hemorrhagic fevers
   - Not used previously by terrorists.
   - Neurological and respiratory symptoms
   a. Filovirus: Ebola and Murburg
   b. Bunyavirus: Crimean-Congo virus

Question 14

Most bioterrorism
agents target

Answer 14

1. respiratory systems
2. Nervous system
3. Cardiovascular system

Question 15

List B

Answer 15

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

Question 16

List C

Answer 16

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.

Question 17

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

Question 18

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

Answer 18

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

Question 19

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

Answer 19

Question 20

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

Answer 20

1. Aquatic
2. Domestic/urban
3. Sylvatic (wildlife)

Question 21

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

Answer 21

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

Question 22

List the Fish-borne zoonotic bacterial diseases

Answer 22

Question 23

Answer 23

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

Question 24

Answer 24

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

Question 25

Answer 25

Man with a tender nodule on the dorsum of his right hand (‘swimmer granuloma’) caused by Mycobacterium marinum Also causes pneumonia?

Question 26

Diphyllobothrium is the ?

Answer 26

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)

Question 27

Fishborne zoonotic parasites of humans?

Answer 27

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

Question 28

 Reptiles are a natural reservoir with very high prevalence of ____________.  Reptiles have relatively high contribution to human infections, especially in _______.

Answer 28

Salmonella, children

Question 29

Mosquito-borne vial zoonosis

Answer 29

1. Zika 2. EEE 3. Western Equine Encephalitis 4. West Nile Virus 2-4 --> bite from Culex mosquito --> brain eating viruses

Question 30

Bacte4rial zoonosis

Answer 30

. 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

Question 31

Protozoa zoonosis

Answer 31

1. Cryptosporidium 2. Giardia 3. Leishmania:  bite of sand flies from lizards

Question 32

Zoonotic worms that come from birds?

Question 33

Avian-borne zoonosis

Answer 33

 Avian influenza  Coronavirus (SARS) * Chikungunya  Japanese encephalitis virus  Eastern equine encephalitis virus * West Nile virus  New Castle disease  etc

Question 34

Avian-borne bacterial zoonosis

Answer 34

 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.

Question 35

Answer 35

Contact with nasal secretion:  Chlamydia psittaci Transmit psittacosis

Question 36

Answer 36

Pasteurella multocida

Question 37

Fungus from birds

Answer 37

1. Cryptococcus neoformans:  contact with feces of infected pigeons and starlings 2. Histoplasma capsulatum:  breath of infected pigeon or bat feces

Question 38

Protozoa from birds?

Answer 38

1. Cryptosporidium:  contact with feces of infected birds or foodborne by ingestion under cooked meat and eggs

Question 39

Pet-borne zoonotic parasites

Answer 39

toxocara is a roundworm, nematode. Larave penetrate our skin and cause cutaneous larva migrans

Question 40

Pet-borne vector-borne zoonotic disease

Answer 40

Bite of dogs transmits 90% of rabies

Question 41

Pet-borne zoonosis transmission routes to humans

Answer 41

Question 42

Rabies, echino, barto --> severe if happens

Answer 42

Question 43

Important livestock & poultry-borne zoonosis of humans

Answer 43

Bovine TB, chlamydia, listeria, Q fever --> humans Pig trich, swine, Hep E, etc --> humans Horses:

Question 44

How many serotypes of Salmonella exist?

Answer 44

2500 different serotypes of Salmonella have been recognized

Question 45

Salmonella bacteria are widespread in the: 1. environment and 2. Animals` gastrointestinal tract:  fish  amphibians  reptiles,  birds,  mammals

Question 46

What is the role of wildlife, rodents, bats, wild birds, their movements & their contacts with humans (e. g. bush meat) in zoonosis

Answer 46

Question 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

Question 48

Rodent viruses

Answer 48

Question 49

Rodent bacteria

Answer 49

Question 50

Zoonosis classification based on transmission routes AKA 7 F's

Answer 50

Question 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

Question 52

Zoonosis transmitted by damaged skin?

Answer 52

 Anthrax  Erysipelothryx  Pasteurella

Question 53

Route of transmission of zoonotic pathogens

Answer 53

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

Question 54

Zoonotic disease control

Question 55

Control of zoonotic diseases

Question 56

. Eliminate zoonosis by eliminating its source

Answer 56

– 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)

Question 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

Question 58

Question 59

Rather than mass culling/killing or mass medication, mass vaccination of animals against zoonosis. How?

Answer 59

Q fever --> 20 km Mycobacterium --> 10 km

Question 60

How much proportion of animals in the population be vaccinated to control zoonosis?

Answer 60

Question 61

Licensed animal vaccines have double function: immunization of animals reduces zoonotic disease transmission to human

Answer 61

Question 62

Vaccination or medication of humans to protect them from zoonosis

Answer 62

Question 63

How to 5. Break/control the transmission routes of zoonosis

Answer 63

Question 64

Minimize unnecessary intensive contact with animals whose health condition is not tested  Children  Pregnant  elderly  immune-compromised humans

Answer 64