Friends! Veterinary medicine is a highly respected and compassionate profession. However, its contributions are largely unappreciated because our colleagues have been too busy serving the public to publicize their contributions to animal and human health, animal welfare, food safety and food security

Veterinary Public Health andZoonoses

Dr. Nicole Seng Lai Giea

Recent zoonoses

BSE Hendra virus Nipah virus Menangle viral infection SARS RVF ( never seen outside Africa

before 2000, outbreaks in Arabian peninsula in 2000)

HPAI

Important zoonoses in Malaysia Rabies JE Nipah virus Brucellosis Contagious ecthyma Meliodosis tuberculosis Leptospirosis Toxoplasmosis Salmonellosis Staphylococcal

infection

Ornithosis Cat scratch disease Dermatomycosis Erysipelothrix Campylobacteriosis Dirofilariosis Sporothrichosis Q-fever influenza monkeypox

Veterinary Public Health

Is seen by WHO “ as a linkage between veterinary medicine and human health

Aim: promote the well being, protect and improve the quality of life

Human health

Veterinary public health

Veterinary

medicine

VPH

“ the contribution to the complete physical, mental and social well being of humans through an understanding and application of veterinary medical science ”(WHO, 1999)

What can we do for you?

Food production

Transportation & Working activities

Animal products eg: clothing

Recreation

Zoonoses

Those infections which are naturally transmitted between vertebrate animal and man

Animals act as reservoir for causative agents

Zoonoses impacts

Affect well-being of man – morbidity, mortality, and anxiety

Loss of animals—dead, culled, destroyed

Loss of productivity – prevent eficient production of food

Obstacles to international trade in animals and animal products

Social and economic losses

Man and animal relationship

Anthropozoonosis

A zoonotic disease maintained in nature primarily by animal to animal transmission of the infectious agent

rabies bovine tuberculosis cat scratch disease brucellosis

Zooanthroponosis

• an infectious disease in which a disease causing agent carried by humans is transferred to other animals

• It may cause the same disease or a different disease in other animals

• It can also be defined as a human-to-human infection with no animal vector

Zooanthroponosis

Zooanthroponosis

the zoonoses include infectionn transmitted from

humans to animals human

tuberculosis

Amphixenosis

zoonotic disease maintained in nature both by animal to animal and human to human transmission

staphylococcosis, streptococcosis, influenza

Classification of zoonoses based on transmission mode

1. Direct zoonoses Require one vertebrate species to propagate

V1 ---------------------V1 No developmental change or propagation of the

organism occurs during the transmission eg: rabies, brucellosis

2. Cyclozoonosis Require at least two (2) vertebrate species, no

invertebrate speciesV1----------V2----------V1

eg: taeniasis,

3. Metazoonosis Require a vertebrate and an invertebrate species ,

agents multiplies and/or develops in an invertebrate host before transmission

V1---------iv---------V1 eg: babesiosis

4. Saprozoonosis Requires a vertebrate species and an in inanimate

object or a non-animal development site such as plants, soil, and foods

V1---------O---------V1 Mycotic diseases

Components of infectious disease process

Infectious agents Reservoirs Portal of entry Mode of transmission Host immunity

Infectious agents: an organism that is capable of producing infection

Infection: entry, development or multiplication of an infectious agent in the body of man or animals, the result may be inapparent (subclinical) or shows clinical manifestation (infectious disease)

Inapparent infection: the presence of infection in the host without recognizable clinical signs or symptoms, they are usually detected through diagnostic test (host=carrier)

Infectious disease: a clinical manifest disease o man or animal resulting from an infection

Communicable disease:  an infectious disease transmissible 

（ as from person to person) by direct contact with an affected individual’s discharges or by direct means (as by a vector)

Contagious disease : an infectious disease communicable by contact with one who has it, with a bodily discharge of such a patient, or with an object touched by such a patient or bodily discharge (indrect means)

Infectious agents

Bactria--anthrax, brucellosis Virus—rabies and influenza Parasit--Cysticercosis/Taeniasis Rickettsia Fungus--sporotrichosis.  Chlamydia--psittacosis Prion -- variant Creutzfeldt-Jakob

Disease (vCJD)

Modes of transmission of infectious agents

Direct Indirect Air-borne

Modes of transmission of infectious agents

Direct transmission: immediate transfer of an organism

to receptive portal of entry in man through which infection may take place

a. Direct contact– touching, biting, scratching

b. Direct projection – projection of droplet spray onto conjunctiva or mucous membrane or mouth

Modes of transmission of infectious agents

Indirect transmission: transmission of infectious organism from the

source/reservoir through contaminated materials or objects or vectors

a. vehicle-borne – by any non-living(inanimate) or objects (fomites) which serves as intermediate

means by which the organism are transmitted to susceptible host

b. vector-borne- by living arthropod, such as insects , mites, ticks, fleas which transmit the infective form of agent to susceptible host

b. I mechanical host b. II biological host

Vector-borne

Mechanical host: Infectious agents are carried through its

soiled feet or proboscis or by the passages o the agents in the GIT

Biological host: Infectious agents undergo propagation/ multiplication ,cyclic development or a

combination to become infective forms before they are transmitted

Airborne

Dissemination of microbial aerosols to a suitable portal of entry, usually the respiratory tract

Microbial aerosols suspensions of particles in the air or a long

periods of time consisting of partially or wholly of

microorganisms, some retaining and other losing virulence

Small size (1-5µm) are easily drawn into the alveoli

a. Droplet nucleib. dust

Modes of transmission

Reservoir ( of an infectious agent)

Is the normal habitat in which the infectious agent lives, multiplies and grows that can be transmitted to a susceptible host

Types of carrier Inapparent carrier Incubatory carrierConvalescent carrier

Portal of entry

Six portals in the bodyRespiratory tractConjunctivaUrogenital tractGITSkin (intact, broken, abraded)placenta

Host immunity

Host immunity

Animals and meBeneficial or hazardous

??

What can you do?

Functions of veterinarians and personals in VPH

Control and prevention of zoonoses Safety of foods of animal origins Disposal of animal waste Comparative medicine Laboratory animal Hazardous/toxic animal

Functions of veterinarians and personals in VPH

Diagnosis, surveillance, epidemiology, control, prevention and elimination of zoonoses

Food protection,meat inspectation Management of health aspects of laboratory animal

facilities and diagnostic laboratories Biomedical research Health education and extension; and production

and control of biological products and medical devices

Other VPH core domains may include management of domestic and wild animal populations, protection of drinking-water and the environment, and management of public health emergencies

Conclusion

We, the Vets, through our remit to facilitate and encourage veterinary development and services, we can improve the health and welfare of both human and animals