Zoonoses

Question 1

Agents of infectious disease

Answer 1

Parasites
Bacteria
Fungi
Viruses
Prions

Question 2

Zoonotic disease examples

Answer 2

Plague
Salmonella
Taeniasis (tapeworm)

Question 3

Zoonoses

Answer 3

Diseases and infections which are naturally transmitted from vertebrates and humans and vice-versa

Question 4

“Diseases and infections”

Answer 4

Diseases caused by animals which are not infected -bites, venom, allergy

Question 5

“Naturally”

Answer 5

Experimental transmission

Question 6

“Transmitted”

Answer 6

Shared diseases

Botulism, rickets

Question 7

“Vertebrates”

Answer 7

If only arthropods involved in cycle- not zoonosis

Question 8

“Vice-versa”

Answer 8

Animal to human and human to animal

Sometimes never seen in real life (rabies)

Question 9

Anthropo-zoonoses

Answer 9

From humans to animals

Question 10

Saprozoonoses

Answer 10

Vertebrate + environment
In sapronosis or geonosis there is disease resulting from a causative agent present in an all natural source, such as soil and water

Question 11

Food-borne infections and zoonoses

Answer 11

Some food-borne: no vice-versa, no vertebrate
Not all food-borne infections are zoonoses (Hep A)
Some zoonoses are food-borne diseases (Anthrax)

Question 12

Not zoonosis anymore

Answer 12

HIV- had zoonotic origin, but no more transmission

SIV–> HIV

Question 13

Percent of pathogens zoonotic

Answer 13

60%

Question 14

Emerging Zoonosis

Answer 14

A zoonosis that is newly recognized or newly evolved, or that has occurred previously but shows an increase in incidence or expansion in geographical, host or vector range

Question 15

Emerging Infectious Diseases

Answer 15

Diseases whose incidence in humans has increased in the past 2 decades or threaten to increase in the future

Question 16

Current emerging zoonoses

Answer 16

Ebola
Echinococcosis
Dog rabies
Avian flu
BSE
Brucellosis

Question 17

Importance of zoonosis

Answer 17

More than 800 diseases mutually transmitted
At least 61% of all pathogens of human beings
75% of all emerging pathogens during the past decade

Question 18

Who is at risk

Answer 18

General population

• children younger than 5
• adults older than 65
• people with weakened immune systems

Question 19

Exposure: Agriculture

Answer 19

Farmer or other people in close contact with livestock or their products

Question 20

Exposure: Animal product processing and manufacture

Answer 20

Personnel of abattoirs and processing plants

Question 21

Exposure: Forestry, outdoors

Answer 21

Persons frequenting wild habitats for professional pr recreational reasons

Question 22

Exposure: Recreation

Answer 22

Persons in contact with pets and/or wild animals in urban encironment

Question 23

Exposure: Clinics, labs

Answer 23

Health personnel and other health workers (including lab) who handle specimens, organs, corpses

Question 24

Exposure: Epidemiology

Answer 24

Public health professionals who do field research

Question 25

Exposure: Emergency

Answer 25

People affected by catastrophes, refugees, or people temporarily living in crowded or highly stressful situations

Question 26

Severity of zoonoses

Answer 26

Some are almost always deadly (rabies) Some severe Mild/moderate (foot and mouth disease) Some severe due to numbers

Question 27

Clinical signs

Answer 27

Human: sick Animal: no signs - chlamydia psittaci Human: sick Animal: sick --- Rabies Human sick: Animal: no signs --TB

Question 28

RNA viruses

Answer 28

``` no proofreading mechanism Each cycle: great number of genetic variant Unable to reproduce Extend of host range Zoonoses Measles, mumps are not not zoonotic ```

Question 29

DNA viruses

Answer 29

DNA polymerase proofreading mechanism Greater genetic stability Restricting host range Poxviruses and some herpesvirus

Question 30

Bacterial zoonoses

Answer 30

All tranmission route (bites/scratch, inhalation, food, vectors, soil and water) Problem of antimicrobial resistance Risk for veterinarian: hundreds of bacteria in the oral cavity

Question 31

Parasitic zoonoses

Answer 31

``` Various cycles: human can be final, intermediate or paratenic host Multiple types of agents: -protozoa -Helminths (nematodes) -Acanthocephala ```

Question 32

Prion zoonoses

Answer 32

Proteinaceous infectious particles Infectious protein Long incubation (several years) Always fatal: neurodegeneration Animal prion: bocine spongiform encephalopathy Human prion: new varient creutzfeld-jacob (not zoonoses)

Question 33

Fungus Zoonoses

Answer 33

Dermatophytoses/Ringworm: Keratinophilic fungi

Question 34

Case 1: Lyme disease

Answer 34

Agent: Borrelia burgdorferi Transmission route: Indirect by vector, the hard tick The most important reservoirs are rodents It is reportable to the CDC

Question 35

Case 2: Brucellosis

Answer 35

It is a bacteria, Brucella Transmission sources are multiples, direct, indirect by fomites or vehicle The most important reservoir is cattle. Goats are the reservoir for B. melitensis, the most pathogenic species In the US you have to notify to both CDC and USD, it is a bioterrorism agent category B

Question 36

Case 3: Sin nombre

Answer 36

It is a Bunyaviridae (RNA) virus It produces the hantavirus pulmonary syndrome (HPS) The main transmission route is either direct or indirect through fomites or vehicles, for example, feces in dust The most important reservoir are rodents It is a notifiable disease in the US, to the CDC (bioterrorism Agent cat. C)