Zoonoses are infectious diseases that can be transmitted between animals and humans. A majority (61%) of known human pathogens are zoonotic. Significant zoonotic pandemics in history include the Black Death plague pandemic in the 14th century spread by Mongol invaders, and the 1918 Spanish flu pandemic. Today, zoonotic diseases pose a threat through increased human-animal contact and potential use in biological terrorism. Bacillus anthracis, the cause of anthrax, is a large, spore-forming, gram-positive rod-shaped bacterium. Its virulence depends on its polysaccharide capsule and lethal and edema toxins. Anthrax is typically transmitted through contact with infected animals or their products and

1. Zoonoses [zo ' nəs s] pathogensʊ ɒ ɪ

2. A zoonosis or zoonose is any infectious disease that can
be transmitted between species (in some instances, by a vector)
from animals to humans or from humans to animals (the
latter is sometimes called reverse zoonosis or anthroponosis).
In a study of 1415 pathogens known to affect humans, 61%
were zoonotic [ zo ə'no t k].ˌ ʊ ʊ ɪ
Overview
Zoonosis

3. History
Interactions between animals and
humans have occurred since the
beginning of time.
As animals became domesticated
and a close bonds developed
between animals and humans, the
occurrence of zoonotic diseases
increased.

4. Significant Zoonitic Pandemics
1700s, Mongols ['m ŋ lz]ɒ ɡ 蒙古人
invaded Europe
Mongols carried plague with them
This lead to “black death” or plague
pandemic
Killed 1/3 of European [ j r 'pi n]ˌ ʊ ə ːə
population

5. Significant Zoonitic Pandemics
Early 1900’s
“Spanish flu” transmitted from pigs
to humans
Decimated ['des me t] 20 millionɪ ɪ
people worldwide
Continues to pose a threat to
humans

6. Today’s threat involving zoonotic
diseases is considered to be partly
due to human involvement in which
the artificial multiplication of these
pathogens can be used as
biological terrorism.
Contemporary Threats

7. Prevalence
 Largely Unknown
 Both serological studies and anecdotal [ æn k'do tl]ˌ ɪ ʊ
轶事的 discussion have been used to generate
estimates
 1997 a study trying to assess [ 'ses]ə the prevalence of
antibodies against Bartonella henselae and B.
quintana 昆塔纳 was done at a veterinary
conference. The results indicated that 7.1% of the
veterinary population had antibodies which was no
different from the general population studies at an
earlier time.

8. Types of Pathogens
 Viruses
 Bacteria
 Fungi
 Others
 Rickettsia
 Protozoa [ pr t 'z ]ˌ əʊ ə əʊə
 Parasites
Always assume every
animal is shedding
pathogens

9. How Diseases Spread
Fecal-oral
Fecal contamination is not always
obvious
Many pathogens may survive for
long periods of time in the
environment.
Parvovirus['p vo va r s]ɑː ʊˌ ɪ ə 细小病毒 ,
ringworm and some worm eggs
can survive for years

10. How Diseases Spread
By air
(aerosol)
Upper
respiratory
infection (URI-
cats)
Kennel （ Ken
nel ）狗舍
cough (dogs)

11. How Diseases Spread
 Aerosol
 Aerosols travel only 3-4 feet, so dividers [d 'va d z]ə ɪ ə
分隔物 between cages help
 12-15 fresh “air exchanges” per hour minimum is
recommended
 “Air change” is also good
 Open windows or fan brings outside air in
 After moving through the room, another fan blows air back
outside
 Fans blowing directly on animals can spread disease by
creating aerosols

12. How Diseases Spread
Animal bites or
saliva
Feline ['fi la n]ː ɪ 猫科
动物 leukemia
FIV （ Feline
Immunodeficiency
Virus ）
Rabies
Bacteria that can
cause bite wound
abscesses

13. How Diseases Spread
Animal bites or saliva
Saliva spread (FeLV ， Feline
Leukemia Virus):
Grooming each other
Sharing food and water bowls
FIV and Rabies require bites, not
just friendly casual contact

14. How Diseases Spread
Through direct
contact
Ringworm
Scabies
['ske bi z]ɪ ː 疥疮
Ear mites
Hookworm
larvae

15. How Diseases Spread
 By insect “vectors”
 Mosquitoes spread heartworms and encephalitis
 Fleas spread tapeworms, cat scratch fever,
plague, typhus, etc.
 Ticks spread Lyme disease, Rocky Mountain
Spotted Fever, and more
 Vectors must be controlled in the shelter
 Eliminate standing water (mosquitos)
 Treat fleas on animals and in environment
 Keep grass cut to limit ticks

16. How Diseases Spread
By infected objects (fomites)
Ringworm spread by spores on pet
hair
Cage walls, toys, and bedding
Peoples’ hands – including staff!

17. 12 Tips to Help You Avoid
Zoonotic Diseases
 Stay current on appropriate vaccinations (tetanus,
rabies)
 Wash hands frequently with antibacterial soap
 before eating or smoking
 After handling each animal or cage
 Wear long pants and sturdy ['st rdi]ɜː 坚固的 shoes
or boots
 Use gloves
 Wear safety glasses and mask when spray cleaning
 Disinfect scratches and bite wounds thoroughly,
then cover them.

18. 12 Tips to Help You Avoid
Zoonotic Diseases
 Don’t allow animals to lick your face or any
open wounds
 Learn safe & humane animal-handling
techniques, and user proper equipment
 Seek assistance when handling questionable
animals
 Report any bites or injuries to supervisor
 Tell your physician where you work
 Consider other work if you are
immunosuppressed.

19. ※ Bacillus anthracis ( 炭疽芽孢杆菌 )
※ Yersinia pestis ( 鼠疫耶尔森氏杆菌 )
※ Brucella ( 布鲁氏菌 )
※ Francisella ( 弗朗西斯氏菌属 )
※ Coxiella ( 考克斯氏体属 )
※ Bartonella ( 巴尔通氏体属 )
……※
Common zoonoses pathogens

20. Bacillus anthracisBacillus anthracis
Robert Koch’s original micrograhps of the anthrax bacillus

21. ※ Large (1 - 3 µm in width × 5 – 10 µm
in length), G+ rod with a tendency to
form very long chains.
※ Facultative anaerobe
※ Glutamyl-polypeptide capsule
※ Nonmotile
※ Forms oval, centrally located
endospores and the spore remain viable
in soil for decades
Biological character

22. 2. Cultural character
On blood agar, nonhemolytic colonies characterized
by a rough, uneven surface with multiple curled extensions
at the edge resembling a “Medusa[mə'dju sə]head”ː
Colonies of Bacillus anthracis on blood agar.

23. Mucoid colonies of Bacillus anthracis. This
culture was probably incubated at an
increased CO2 tension (5% CO2) which
greatly enhances production of the poly-D-
glutamyl capsule and accounts for the
mucoid colony type.
2. cultural character

24. PathogenesisPathogenesis
Virulence depends onVirulence depends on 2 factors2 factors
※※ CapsuleCapsule
※※ 3 toxins3 toxins

25. CapsuleCapsule
C=Capsule; S=S-layer; P=Peptidoglycan
※※ Coded by pX02 plasmidCoded by pX02 plasmid
※※ Made up ofMade up of D-glutamic acidD-glutamic acid
※※ Non-toxic on its ownNon-toxic on its own
※※ Only encapsulatedOnly encapsulated B. anthracisB. anthracis
virulentvirulent
※※ Most important role duringMost important role during
establishment of diseaseestablishment of disease
△△ Protects against phagocytosis & lysisProtects against phagocytosis & lysis
during vegetative stateduring vegetative state

26. ToxinsToxins
※ Coded by pX01 plasmid
※ AB model
△ Binding
△ Activating
※ Protective antigen (PA), edema factor (EF) & lethal
factor (LF)
△ Make up 50% of proteins in the organism
※ Heterogeneous protein complex made up of 3
components

27. ToxinsToxins
△ Individually non-toxic
△ PA+LF  lethal activity
△ EF+PA  edema activity
△ EF+LF  inactive
△ PA+LF+EF  edema & necrosis; lethal

28. ※※ Protective antigen (PA, 83kDa)Protective antigen (PA, 83kDa)
△△ PagPag genegene
△△ Binds to receptor & helps internalize other 2 proteinsBinds to receptor & helps internalize other 2 proteins
※※ Edema factor (EF, 89 kDa)Edema factor (EF, 89 kDa)
△△ CyaCya genegene
△△ Adenylate cyclase [ə'den le t] ['sa kle s]ɪ ɪ ɪ ɪAdenylate cyclase [ə'den le t] ['sa kle s]ɪ ɪ ɪ ɪ
△△ Affects all cellsAffects all cells
※※ Lethal factor (LF, 87 kDa)Lethal factor (LF, 87 kDa)
△△ LefLef genegene
△△ More important virulence factorMore important virulence factor
△△ Metalloprotease (Metalloprotease ( 金属蛋白酶 )[met l p'r ti z]ə əʊ əʊ ː
△△ Cleaves mitogen ['ma təd ən]activated protein kinase kinase(MAPKKɪ ʒCleaves mitogen ['ma təd ən]activated protein kinase kinase(MAPKKɪ ʒ
△△ Affects only macrophagesAffects only macrophages
ToxinsToxins

29. OutcomeOutcome
※※ Do not understand exactly how symptoms occurDo not understand exactly how symptoms occur
※※ EF convertsEF converts ATP to cAMPATP to cAMP
△△ Increases cAMP levels over 1,000 foldIncreases cAMP levels over 1,000 fold
△△ Impairs neutrophil functionImpairs neutrophil function
△△ Alters water homeostasisAlters water homeostasis
■■ EdemaEdema

30. OutcomeOutcome
※※ LF cleaves MAPKKLF cleaves MAPKK at its N terminusat its N terminus
△△ Disrupts pathways involved in cell growth & maturationDisrupts pathways involved in cell growth & maturation
△△ Increased synthesis of tumor necrosis factor-Increased synthesis of tumor necrosis factor-αα &&
interleukin-1interleukin-1ββ
△△ Macrophage lysisMacrophage lysis
■■ Septic shock & deathSeptic shock & death
※※ Death probably results from high levels of bacteria secretingDeath probably results from high levels of bacteria secreting
LF toxins in bloodLF toxins in blood
△△ At death, blood contains as many asAt death, blood contains as many as 101099
bacilli/mlbacilli/ml
(depending on the species)(depending on the species)

31. Anthrax: transmissionAnthrax: transmission
※※ Anthrax is a major disease threat to herbivorousAnthrax is a major disease threat to herbivorous
[h 'b vərəs]animals.ɜː ɪ[h 'b vərəs]animals.ɜː ɪ
※※ People become infected by thePeople become infected by the cutaneouscutaneous route (directroute (direct
contact with diseased animals, industrial work with hides,contact with diseased animals, industrial work with hides,
wool, brushes, or bone meal), bywool, brushes, or bone meal), by inhalationinhalation (Woolsorter's(Woolsorter's
diseasedisease 拣毛工病 ), or by), or by ingestioningestion (meat from diseased(meat from diseased
animals).animals).
Clinical InformationClinical Information

32. Three forms of AnthraxThree forms of Anthrax
※※ CutaneousCutaneous anthraxanthrax
△△ SkinSkin
△△ Most commonMost common
△△ Spores enter to skin through small lesionsSpores enter to skin through small lesions
※※ InhalationInhalation anthraxanthrax
△△ Spores are inhaledSpores are inhaled
※※ GastrointestinalGastrointestinal (GI)(GI) anthraxanthrax
△△ Spores are ingestedSpores are ingested
△△ Oral-pharyngeal and abdominal[æb'd m nl]ɑː ɪOral-pharyngeal and abdominal[æb'd m nl]ɑː ɪ

33. ['pæpju l]ː 丘疹
['esk ]ɑː 焦痂

35. [hi m 't d n s]ː ə ɒ ʒɪ ə 造血的

36. [ sept 'si m k]ˌ ə ː ɪ
[ ent 'ra t s]ˌ ə ɪ ə

37. 肺内炭疽
内炭疽肠
脾内炭疽

38. Laboratory diagnosis of anthraxLaboratory diagnosis of anthrax
※※ Gram stainGram stain
※※ Culture ofCulture of B. anthracisB. anthracis from the blood, skin lesions,from the blood, skin lesions,
vesicular [və's kj lə]fluid, or respiratory secretionsɪ ʊvesicular [və's kj lə]fluid, or respiratory secretionsɪ ʊ
※※ Rapid detection methodsRapid detection methods
△△ PCR for detection of nucleic acidPCR for detection of nucleic acid
△△ ELISA assay for antigen detectionELISA assay for antigen detection
△△ Other immunohistochemical and immunoflourescenceOther immunohistochemical and immunoflourescence
examinationsexaminations

39. Bacillus anthracisBacillus anthracis in Gram stainin Gram stain
Gram Stain AnalysisGram Stain Analysis
△△ Useful for cutaneous and inhalationUseful for cutaneous and inhalation
anthrax.anthrax.
△△ A blood sample or skin lesion isA blood sample or skin lesion is
taken from the patient and culturedtaken from the patient and cultured
forfor 6 to 24 hours6 to 24 hours..
△△ Identify whether the bacteria comeIdentify whether the bacteria come
from the anthrax category.from the anthrax category.

40. Treatment of anthraxTreatment of anthrax
※※ antibioticsantibiotics
※※ Antibody to the toxin complex is neutralizing andAntibody to the toxin complex is neutralizing and
protectiveprotective

41. Binding of a Neutralizing Antibody to the Protective
Antigen Subunit of the B. anthracis toxin
Neutralizing Antibodies to B. anthrax toxin

42. Defense: Protection Against AnthraxDefense: Protection Against Anthrax
※※ VaccinationVaccination
Very Effective: 2 dose efficacy against up to 1,000Very Effective: 2 dose efficacy against up to 1,000
LD50 in monkeys (human response believed to be veryLD50 in monkeys (human response believed to be very
similar)similar)
※※ Early DetectionEarly Detection
Extremely important: eliminate much of danger.Extremely important: eliminate much of danger.
Time lag between exposure and symptoms is primaryTime lag between exposure and symptoms is primary
reason for the high mortality rate experienced withreason for the high mortality rate experienced with
anthrax infectionsanthrax infections

43. ※※ Contaminated animal, carcass or hide should be burned.Contaminated animal, carcass or hide should be burned.
※※ Pre/Post Exposure Antibiotic TreatmentPre/Post Exposure Antibiotic Treatment
※※ Decontamination of Exposed AreasDecontamination of Exposed Areas
※※ Use of Protective Clothing & EquipmentUse of Protective Clothing & Equipment
Defense: Protection Against AnthraxDefense: Protection Against Anthrax

44. Exercises:
1.Briefly describle the three forms of Anthrax?1.Briefly describle the three forms of Anthrax?
2.Briefly describle the mechanism of anthrax2.Briefly describle the mechanism of anthrax
toxintoxin