Veterinary Public Health and Zoonoses

1. 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

2. Dr. Nicole Seng Lai Giea Veterinary Public Health andZoonoses

3. 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

4. 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

5. 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

6. 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)

7. What can we do for you?

8. Transportation & Working activities Recreation Food production Animal products eg: clothing

9. Zoonoses • Those infections which are naturally transmitted between vertebrate animal and man • Animals act as reservoir for causative agents

10. 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

11. Man and animal relationship

12. Anthropozoonosis • A zoonotic disease maintained in nature primarily by animal to animal transmission of the infectious agent • rabies • bovine tuberculosis • cat scratch disease • brucellosis

13. Zooanthroponosis 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

14. Zooanthroponosis • the zoonoses include infectionn transmitted from humans to animals • human tuberculosis

15. Amphixenosis • zoonotic disease maintained in nature both by animal to animal and human to human transmission • staphylococcosis, • streptococcosis, • influenza

16. 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 species V1----------V2----------V1 • eg: taeniasis,

17. 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

18. Components of infectious disease process • Infectious agents • Reservoirs • Portal of entry • Mode of transmission • Host immunity

19. 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)

20. Infectious agents • Bactria--anthrax, brucellosis • Virus—rabies and influenza • Parasit--Cysticercosis/Taeniasis • Rickettsia • Fungus--sporotrichosis.  • Chlamydia--psittacosis • Prion -- variant Creutzfeldt-Jakob Disease (vCJD)

21. Modes of transmission of infectious agents • Direct • Indirect • Air-borne

22. 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 • Direct contact– touching, biting, scratching • Direct projection – projection of droplet spray onto conjunctiva or mucous membrane or mouth

23. 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

24. 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

25. 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 • Droplet nuclei • dust

26. Modes of transmission

27. 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 carrier • Convalescent carrier

28. Portal of entry • Six portals in the body • Respiratory tract • Conjunctiva • Urogenital tract • GIT • Skin (intact, broken, abraded) • placenta

29. Host immunity

30. Host immunity

31. Animals and me Beneficial or hazardous??

32. What can you do?

33. 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

34. Functions of veterinarians and personals in VPH • Diagnosis, surveillance, epidemiology, control, prevention and elimination of zoonoses • Food protection,meatinspectation • 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

35. 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