2. • Scope
Definition
Epidemiology
Factors influencing prevalence
Stages of zoonotic diseases
Modes of transmission
Persons at risk
Classification
Viral zoonoses – classification, general clinical features,
diseases in brief
Laboratory diagnosis
Treatment
Prevention
4. •The word 'Zoonosis' (Pleural: Zoonoses) was
introduced by Rudolf Virchow in 1880 to include
collectively the diseases shared in nature by man and
animals.
• Later WHO in 1959 defined that Zoonoses are "those
diseases and infections which are naturally transmitted
between vertebrate animals and man".
(http://www.who.int/topics/zoonoses/en/)
• Zoonoses include only those infections where there is
either a proof or a strong circumstantial evidence for
transmission between animals and man.
• Zoonotic Diseases (also known as zoonoses) are
caused by infections that are shared between animals
and people. (https://www.cdc.gov/onehealth/basics/zoonotic-diseases.html)
8. FACTORS INFLUENCING PREVALENCE
OF ZOONOSES
• Ecological changes in man's environment
• Handling animal by-products and wastes
(occupational hazards)
• Increased movements of man
• Increased trade in animal products
• Increased density of animal population
• Transportation of virus infected mosquitoes
• Cultural anthropological norms
12. Who are at Risk?
I. Farmers, livestock and animal processing workers
II. Outdoor recreational activities or vocational activities
in wild or underdeveloped regions
III. Persons in contact with pets, other animals in urban
areas
IV. Health care and laboratory personnel (human and
veterinary)
V. Fishers and others working in aquatic envirnment
VI. Immunocompromised hosts;
Public, anyone, any place
14. • When an insect vector is involved, the disease
is also known as an arboviral disease.
• However, not all arboviral diseases are
zoonosis: where the transmission cycle takes
place exclusively between insect vector and
human e.g. dengue and yellow fever.
16. Through the Arthropod vector
Arboviral Infections
*Fever with arthrits
- Chikungunya
- Mayaro
- Ross river
- Sindbis
- Semiliki
*Encephalitis
- Japanese enceph.
- West nile enceph.
- Colorado tick fever
- California enceph.
- St. Louis enceph.
- Estern equine
- Western equine
- Venezuelan equine
*Hemorrhagic
- Yellow fever
- Kyasanur forest
disease
- Dengue
- Crimean congo HF
- Omsk HF
17. • According to Zoonotic Diseases of Public Health
Importance (manual) published by Zoonosis Division
of National Centre for Disease Control, Delhi.(20th
July 2016)
• Following viral zoonotic diseases seen in India are:
Rabies
Arboviral Infections
Zika Virus Disease
Crimean-Congo Haemorrhagic Fever
Ebola Virus
19. Zoonoses transmitted by animal
bite
Disease Organism Animal Host Person at
risk
Rabies
(Rhabdoviridae)
Rabies
virus
Dogs, fox,
bats,
cattles
Human
(Accident
al)
II, IV,
Public
Herpes B
encephal
omylitis
(Herpesviridae)
Herpes
simiae
Monkey Human
(rare) II, III, IV
20. Disease World
distribution
India
disribution
Clinical
features
Rabies Worlswide,
rural areas of
Africa and
Asia, (Except
Australia, New
Zealand, UK,
Ireland,
Scandinavia,
Japan and
Taiwan
Except
andaman and
Nicobar
Islands,
Lakshadweep
headache,
malaise, sore
throat and
mild fever,
pain and
tingling,
Aerophobia,
Hydrophobia
Herpes B
encephalomyli
tis
---- ----
Acute
ascending
myelitis
21. Zoonoses transmitted by Direct
contact/skin penetration
Disease Organism Animal Host Person at
risk
Foot &
Mouth ds
Aphthovir
us
Cattle Cattle,
Human
I, III, IV
Orf
(contagio
us
erythema
)
Parapox
virus
Sheep,
goat
Sheep,
goat
human
(rare)
I
22. Disease Organism Animal Host Person at
risk
Vesicular
stomatitis
(Rhabdoviridae)
Vesicular
stomatitis
virus
Cattle,
horses
Cattle,
horses,
human(rar
e)
III, IV
Monkey
pox (Orthopox)
Monkey
pox virus
Rodents/
Monkey
Human II, III
Ebola Filovirus ?Fruit bat
? Primates
(apes/mo
nkeys)
Human I, II, IV
Marburg Filovirus Monkey Human I, II, IV
23. Disease Organism Animal Host Person at
risk
Nipah
virus
Paramyxo
virus
Fruit bat Pigs
Human
(close
contact)
I, II
Hindra
virus
Paramyxo
virus
Fruit bat Horses
Human
(body
fluid
&secreti
ons)
I, II
24. Disease World
distribution
India
disribution
Clinical
features
Foot & Mouth
ds
Worldwide Southern &
western part
(2006)
- Sore throat
- Ulcers in the
throat, mouth
and tongue
- Rash with
vesicles on hands,
feet and diaper
area.
- Loss of appetite
Orf
(contagious
erythema)
Worldwide ---- Localised skin
lesions, mouth
sore (contagious
pustula
dermatitis)
28. Zoonoses transmitted by
Inhalation
Disease Organism Animal Host Person at
risk
Lymphocyti
c
choriomeni
ngitis
Lymphocyti
c
choriomeni
ngitis
(Arenavirus)
Mice,
hamster,
rodents
Human I, III, IV,
Public
Influenza
(Avian/
Pandemic)
Influenza
virus
(Orthomyxo)
Pigs, Birds Human I, II, Public
Hanta virus
HF
Hantavirus
(Bunyaviridae)
Rodents Human I, II, IV
32. Zoonoses transmitted by Ingestion
Disease Organism Animal Host Person at
risk
Lassa fever Arenavirus Mouse
(food
contaminat
ed with
rodent
excreta)
Human I, II
34. Zoonoses transmitted by
Arthropod vector
Disease Organis
m
Vector Animal Host Person
at risk
Yellow
fever
Flavivir
us
Mosqui
to (Aedes
aegypti)
Primate
s
Monkey
Human
II
Japanes
e
enceph
alitis
Flavivir
us
Mosqui
to
( Culex
tritaeniorhynch
us)
Pigs Animal
Birds
Human
(dead
end)
II,
Children
<15 yr
Adults
Infants
not
affected
35. Disease Organis
m
Vector Animal Host Person
at risk
Kyasanu
r forest
disease
Flavivir
us
Tick Monkey
rodent,
squirrel
Monkey
rodent,
squirrel
Man
(incident
al & dead
end)
II
Dengue Flavivir
us
Mosqui
to(Aedes
aegypti)
?Monke
y
Human II,
Public
Chikung
unya
Flavivir
us
Mosqui
to(Aedes
aegypti)
?Monke
y
Monkey
Rodents
II,
Public
36. Disease Organis
m
Vector Animal Host Person
at risk
Zika virus Flavivirus Mosquito
(Aedes aegypti)
Monkey -Human
(Mother to
child
transmission;
Sexual
transmission)
II, Public
Crimean-
congo HF
Bunyaviru
s
Tick Domestic
mammals
, rodents
Human I, IV
37. Disease World
distributio
n
India
disributi
on
Clinical features
Yellow fever Worlwide
Africa
Not in
India
Fever, headache,
myalgia, nausea,
vomiting, hemorrhagic
Japanese
encephalitis
Japan, India,
south
east Asia
Assam, UP,
Bihar,
Haryana,
Goa,
Maharasht
ra, South
India
signs of
increased intracranial
pressure,
difficulty of speech,
ocular palsies,
hemiplegia,
quadriplegia,
tremors, altered
sensorium,
convulsions, coma
39. Disease World
distributi
on
India
disribution
Clinical features
Chikungu
nya
Sub-
Saharan
Africa,
India, many
areas of
Asia
Tamil Nadu,
Kerala,
Karnataka,
Maharashtra,
Madhya Pradesh,
Gujarat,
Rajasthan,
Pondicherry,
Goa,
Orissa, West
Bengal,
UP and
Andaman.
Fever, chills,
vomiting, epistaxis,
petechiae,
arthropathy, pain,
swelling, stiffness of
the
metacarpophalange
a
l, wrist, elbow,
shoulder, knee,
ankle and
metatarsal
joints
42. Disease Organism Vector Animal Person at
risk
Encephalitis
(Eastern equine,
western equine,
venezuelan
equine)
Alphavirus Mosquito
(Aades, culex)
Birds,
horses
II, III, IV,
Public
California Bunyavirus Mosquito
(Aades)
Mammals,
wild
rodents
I, II, Public
St. Louis
Encephalitis
Flavivirus Mosquito
(Culex)
Birds I, Public
West nile
encephalitis
Flavivirus Mosquito
(Aades, culex)
Birds II, Public
43. Disease Organism Vector Animal Person at
risk
Murray
valley
encephalitis
Flavivirus Mosquito
(Culex)
Birds II
Rift valley
fever
Bunyavirus Mosquito
(Aades)
Sheep,
goat, cattle
I, II, IV,
Public
Colorado
tick fever
Orbovirus Tick Rodents I, II
Sandfly
fever
Bunyavirus Sandfly Small
mammals
I, II
44. • Egg innoculation
Yolk sac – JE virus, St. Louis virus,
West nile virus.
Amniotic sac – Influenza virus
Allantoic sac – larger cavity hence
used to derive viral vaccines.
Influenza vaccine
Yellow fever (17D) vaccine
Rabies (Flury strain) vaccine.
46. Disease Laboratory Diagnosis Prevention
Rabies 1. Specimen :
Human –
Antemortem : corneal
smear, skin biopsy
(face/neck), saliva, hair
follicles, blood,
cerebrospinal fluid
Postmortem : brain
(hippocampus,
cerebellum)or spinal cord
suspected rabid animals –
Postmortem : brain and
salivary glands
Antemortem : saliva and
corneal smears
1. Prophylaxis :
Pre-exposure –
Pre-exposure
immunization should be
three full
IM dose of vaccine given
on day 0, 7 and 28 or 0, 28
and 56 followed by
booster at one year and
then a booster every three
years.
Laboratory staff and
others at high continuing
risk of exposure should
have their neutralizing
antibody titres checked
every 6 months. If it is less
than 0.5 i.u./ml a booster
dose of vaccine
should be given
47. Disease Laboratory Diagnosis Prevention
Rabies 2. Direct microscopy :
Demonstration of rabies virus
antigen by Direct FAT
Demonstration of Negri bodies
by Seller’s stain. (other Giemsa
or Mann’s stain)
3. Isolation :
Animal inoculation :
Intracerebral in mice from
brain, CSF and saliva.
Inoculated mice are examined
for signs of illness and their
brains are examined at death
or at 28 days post-inoculation
for Negri bodies.
Post – exposure :
Management of
wound:
- Wound toilet
- Antiseptic
- Local infiltration
of rabies Ig
Passive
immunization :
- Antirabies
serun/ERIG (Equine
Rabies immunoglobulin) 40
IU/kg body wt.
- HRIG (Human Rabies
immunoglobulin) 20 IU/kg body
wt.
49. Disease Laboratory Diagnosis Prevention
Rabies Tissue culture :
WI 38, BHK 21, CER
Cytopathic effect is minimal
Virus isolation is identified by IF
as early as 2-4 days after
inoculation.
4. Antibody demonstration :
By ELISA
Diagnostic role is limited in
antemortem diagnosis as the
disease is largely fatal.
5. Electron Microscopy :
Shows bullet shaped virus
6. Molecular method :
Detection of rabies virus RNA
by RT-PCR
Active
immunization :
-Antirabies
vaccines (Day
0,3,7,14 & 28)
2. Control :
Rabies is
primarily a disease
of animals and
control measures
have to be directed
towards the natural
reservoir of the
disease
Vaccines for
animals
51. Name of the vaccine Fixed virus
strain
Substrate Available
1. Neural tissue vaccine
BPL inactivated sheep
brain vaccine
(Semple type)
PV – 11 Sheep brain Production
stopped since
December 2004
Cell Culture vaccines
i) Human Diploid Cell
Vaccine
(HDCV)
ii) Purified Chick Embryo
Cell
Vaccine (PCEC)
iii) Purified Vero Cell
Rabies
Vaccine (PVRV)
Pitman Moore
(PM)
LEP-Flury
Pitman Moore
(PM)
MRC-5
Primary SPF
chick
embryo cells
Vero Cells
Imported
Produced locally
in pvt. Sector
Imported +
produced locally
in public sector
Purified Duck Embryo
Vaccine
Pitman Moore
(PM)
Duck Embryo Imported
52. Disease Laboratory Diagnosis Prevention
Ebola - Specimen :
Blood/serum/plasma
- ELISA for Ag & Ab
detection
- RT-PCR
- Electron microscopy
- Vero cell line for virus
isolation
- Rodent control
- Avoid contacts
with rodents & their
products
Marburg - Specimen :
Blood/serum/plasma
- ELISA for Ag & Ab
detection
- RT-PCR
- Electron microscopy
- Vero cell line for virus
isolation
- Rodent control
- Avoid contacts
with rodents & their
products
54. Disease Laboratory Diagnosis Prevention
Influenza 1. Specimen :
Nasopharyngeal swab
Throat gargling
Serum and plasma
2. Demonstration of viral
antigen: By IF
3. Isolation of the virus :
During first 2-3 days
Throat gargling using broth
saline or buffered salt
solution.
Isolation may be made in
amniotic cavity of hen’s egg
or in monkey kidney cell
culture.
1. Immunoprophy-
laxis :
Inactivated
vaccine:
Subunit vaccines
Recombinant
vaccines
Live attenuated
vaccines:
intranasal
instillation
Recombinant live
vaccine
55. Disease Laboratory Diagnosis Prevention
Influenza Virus growth identified
by hemadsorption with
human O group,
fowl/guinea pig
erythrocytes.
4. Serology :
Hemagglutination
inhibition : detection of
antibodies
Complement fixation :
RNP antigen
Very useful as
antibodies formed
during infection only
Now used rarely
2. chemoprophylaxis:
Amantadine
Rimantadine
56. Disease Laboratory Diagnosis Prevention
Influenza Radial immunodiffusion :
Identification of
antibodies to RNP
antigen, hemagglutinin,
neuroaminidase
5. Molecular method :
Multiplex PCR
3. General
measures:
Avoid contact
with infected
people
Stay at home if
sick.
Use mask (N95)
Wash your hand
thoroughly and
frequently.
57. Disease Laboratory Diagnosis Prevention
Lymphocytic
choriomening
itis
1. Specimen :
Blood/Serum/Plasma,
CSF, Brain tissue
2. Serum IgM/IgG dection
3. Viral RNA detection by
RT-PCR
4. Viral culture – vero cell
line
- Rodent control
- Avoid contact with
contaminated
material.
58. Disease Laboratory Diagnosis Prevention
Hanta virus
HF
-Specimen :
Blood/serum/plasma, urine,
tissue (renal, liver, lung)
- IgM Antibody detection by
ELISA
- Isolation of viruses
- RT-PCR
- Rodent control
- Protection from
exposure to rodent
droppings and
contaminated
material.
59. Disease Laboratory Diagnosis Prevention
Lassa fever 1. Specimen :
Blood/serum/plasma,
tissue (renal,
cardiac,lung)
2. Serum IgM/IgG dection
3. Viral RNA detection by
RT-PCR
4. Viral culture – vero cell
line
Rodent control
- Protection from
exposure to rodent
droppings and
contaminated
material.
60. Disease Laboratory Diagnosis Prevention
Yellow fever 1. Specimen :
2. Virus Isolation by culture
3. IgM antibody/ antigen
detection by ELISA
4. Neutralisation test (more
specific)
5. Molecular: Real time-PCR
1. Vaccine:
17D vaccine
CRI Kasoli
Single dose- s/c
Certification for 10
years.
2. Control measures:
mosquito control
62. Disease Laboratory Diagnosis Prevention
Japanese
encephalitis
1. Specimen :
Serum
CSF
Brain tissue
(postmortem)
2. Detection of antigen:
from autopsied brain
tissue by fluorescent
antibody test.
3. Isolation of virus:
mosquito cell line from
CSF or brain tissure
4. Detection of antibody:
HAI , IgM capture ELISA
5. Molecular: PCR
Control measures:
1. Interruption of
transmission:
Mosquito control
2. Vaccine:
Live attenuated
:SA14-14-2,
Inactivate vaccine:
nakayama, beijing
vaccine
3. Health education
64. Disease Laboratory Diagnosis Prevention
Kyasanur
forest disease
1. Specimen: serum / blood
2. Detection of
antibody:IgM ELISA
3. Isolation of virus from
blood
4. Molecular : nested PCR
and Real Time -PCR for viral
RNA
1. Protection of
man:
Vaccine:
Killed KFD vaccine-
2 doses at interval of
2 months , boster at
6 to 9 month then
every 5 year
Prevention of tick
bite.
2. Protective
measures against
ticks: lindane
effective for 6 weeks
65. Disease Laboratory Diagnosis Prevention
Dengue 1. Specimen: serum/ plasma/ tissue
(liver, renal)
2. Detection of antigen:
Direct IF
NS1 antigen detection by
immunochromatograpy (flow through
assay)or ELISA
3. Serological diagnosis:
Detection of IgM antibody by
capture ELISA and rapid IgM test .
Detection of IgG antibodies by IgG
ELISA ,rapid IgG and HAI
4. Isolation of virus: suckling mice
tissue culture or mosquitoe cell line
5.Molecular method: real time PCR
1. Vaccine:
No effective
vaccine
available
Dengvaxia
vaccine
2. Vector control
measures
3. Protection
from mosquito
bite
67. Disease Laboratory Diagnosis Prevention
Chikungunya
virus
1. Specimen: blood/ serum
2. Detection of antibody:
IgM ELISA
3. Isolation of virus:
mosquitoe cell lines,
suckling mice inoculation
4. Molecular method: Real
Time-PCR
1. Vector control
measures
2. Protection from
mosquito bite
3. No vaccine is
available.
69. Disease Laboratory Diagnosis Prevention
Zika virus 1. Specimen: blood/ serum
2. Detection of antibody:
IgM ELISA
3. Molecular method: RT-
PCR
1. Vector control
measure
2. Protection from
mosquito bite
3. No vaccine
available
70. Disease Laboratory Diagnosis Prevention
Crimean-
congo HF
(CCHF)
1. Specimen :
Antemorterm:
serum/plasma
Postmorterm : tissue (liver,
spleen, Bone Marrow,
kidney, lung ,brain)
2. Serology:
IgG/IgM antibodies by
ELISA.
3. Isolation if virus from blood
or tissue : vero cell line
4. Molecular detection : RT-
PCR
1. No vaccine
available
2. Tick control
3. Health
education
73. References
• www.who.int/topics/zoonoses/en/
• www.ncdc.gov.in
• www.cdc.gov.in
• Ghasemzadeh I, Namazi SH,Review of bacterial and viral zoonotic
infections transmitted by dogs, J Med Life;2015; 8(Spec Iss 4): 1–5
• Shanson DC, Microbiology in clinical practice, Indian ed; Wrights & Sons
pvt ltd; London, England, 1983, pp 400-11
• Text book of Microbiology, Ananthnarayan, Panikar R; 9
th
edition,2014
• Sastry AS, Sandhya BK; Essentials of Medical Microbiology; Jaypee
brothers Medical Publishers Pvt Ltd, 1
st
edition,2016
• Park’s textbook of Preventive and social medicine; Park K; Bhanot
Publication, Jabalpur, India;24
th
Ed, 2017
• Gandham Pavani, Review Article ZOONOTIC DISEASES WITH SPECIAL
REFERENCE TO INDIA, International Journal of Basic and Applied Medical
Sciences ISSN:2014 Vol. 4 (1) January-April, pp. 73-87.
• J Kay Richmond, Deborah J Baglole, Lassa fever: epidemiology, clinical
features, and social consequences, BMJ 2003;327:1271–5
Notas do Editor
Direct zoonoses- These are transmitted from an infected vertebrate host to a susceptible host (man) by direct contact, by contact with a fomite or by a mechanical vector. The agent itself undergoes little or no propagative or developmental changes during transmission, e.g. rabies, anthrax, brucellosis, leptospirosis, toxoplasmosis.
Cyclozoonoses- These require more than one vertebrate host species, but no invertebrate host for the completion of the life cycle of the agent, e.g. echinococcosis, taeniasis.
Metazoonoses- These are transmitted biologically by invertebrate vectors, in which the agent multiplies and/or develops and there is always an extrinsic incubation (prepatent) period before transmission to another vertebrate host e.g., plague, arbovirus infections, schistosomiasis, leishmaniasis.
Saprozoonoses- These require a vertebrate host and a non-animal developmental site like soil, plant material, pigeon dropping etc. for the development of the infectious agent e.g. aspergillosis, coccidioidomycosis, cryptococosis, histoplasmosis, zygomycosis.
Anthropozoonosis:
Lower vertebrate to human
Zooanthroponosis:
Human to Lower vertebrate
Amphixenoses: Maintained & transmitted
Lower vertebrate Human