ANSWERS

1. Why should animals with respiratory disease be isolated?
   Transmission of respiratory diseases is often by aerosol. Coughing and sneezing creates an aerosol of large numbers of water droplets loaded with micro-organisms into the atmosphere which may infect other susceptible animals sharing the same air space.
2. State the 5 main ways in which infection may establish itself within a new host.
   • Ingestion via infected food/coprophagia.
   • Inhalation.
   • Via the skin.
   • Via the mucous membranes of the mouth, ear, eye and sexual organs.
   • Congenital route.
3. List ways in which infectious agents are excreted from the body.
   • Sneezing.
   • Discharges.
   • Via urine.
   • In faeces.
   • In parasitic ova/larvae.
   • In vomit.
   • In saliva.
4. What is another name given to the congenital route of entry by infection into a new host?
   Vertical transmission.
5. What is the name given to inanimate carriers of disease such as shared food bowls?
   Formites.
6. Give 2 examples of infectious diseases spread by formites.
   • Parvovirus.
   • Ringworm.
7. What is the name given to an invertebrate animal (such as a tick or flea) that carries a parasite from one vertebrate host to another?
   A vector.
8. What is another name for a biological vector?
   An intermediate vector. An example is the flea which is the intermediate host in the lifecycle of the tapeworm; some of the organism's development must occur within the intermediate host which is then ingested by the definitive host.
9. What is another name for a non-biological vector?
   A mechanical vector. Mechanical vectors transmit disease without playing any role as an intermediate host; they simply transfer infection from an affected animal to a susceptible one.
10. What are the 2 sub-divisions of mechanical vector? Briefly describe each and give an example.
    • Transport hosts - these pass on infection to a susceptible host at any time whilst remaining unaffected by the infectious agent (eg. Fleas carrying Haemobartonella felis).
    • Parantenic hosts - these must be eaten by the host in order to pass on infection (eg. Mice which must be eaten by cats in order to cause infection with toxoplasma gondii).
11. List 10 methods of disease control.
    • Isolation.
    • Quarantine.
    • Barrier nursing.
    • Good ventilation (and ensuring that too many animals are not sharing the same air space).
    • Therapy (ensure early and effective treatment of infected animals).
    • Good hygiene.
    • Control of endo and ectoparasites.
    • Vaccination.
    • Import controls.
    • Education.
12. Define the following: isolation and quarantine.
    • Isolation = the physical separation of animals so that both direct and indirect contact becomes very difficult.
    • Quarantine = compulsory isolation that is usually longer than the incubation period of a disease for animals being brought into a country or region.
13. What is meant by modified barrier nursing?
    The prevention of cross-infection by the following means:
    • Keeping a patient within the confines of the same kennel or cage throughout the duration of its hospitalisation period.
    • Using the same utensils for this patient during its hospitalisation period.
    • Ensuring that a protective apron and gloves are worn when handling the patient or any items that it has come into contact with.
    • Ensuring that surgical and non-infectious cases are nursed prior to infectious patients.
14. List the 4 main ways in which an infectious disease is spread by direct contact (ie. an infected animal coming into direct physical contact with another susceptible animal).
    • Housing in the same kennel/cage.
    • Sexual contact.
    • Licking/grooming.
    • Fighting (bites and scratches).
15. You are nursing an isolated cat with cat 'flu. List ways in which you would aim to ensure that the virus is not spread by indirect contact (ie. contamination of the environment).
    • Wear protective clothing when nursing the cat.
    • Only move the cat from the cage for the purpose of examination and treatment.
    • Ensure that the surface upon which the cat is examined is thoroughly disinfected following use - this should be within a designated area well away from non-infected patients.
    • Keep the carrier in which the cat arrived at the surgery away from the baskets belonging to non-infected cats.
    • The cat should be given its own feed bowls, litter tray and bedding to be used throughout the duration of its hospitalisation period. These should be washed up and disinfected well away for those used for non-infected patients.
16. A client telephones the surgery. He suspects that the dog has something stuck in its throat due to the bouts of coughing and retching. He is puzzled, since the dog is not a scavenger, and has definitely not been given any bones or inappropriate toys. What is the most likely possible cause of these symptoms.
    Kennel cough.