Diseases Transmitted by Animals and Insects

Question 1

What are zoonoses?

Answer 1

Infections that occur in both animals and humans

Question 2

What is direct transmission between animals and humans?

Answer 2

Transmission by direct animal human contact

Question 3

What is indirect transmission between animals and humans?

Answer 3

Transmission involved a vector

Question 4

Name three common vectors.

Answer 4

Mosquito
Tick
Flea

Question 5

Why is it difficult to control zoonoses?

Answer 5

Because they have a complex infection cycle

Question 6

How can the susceptibility of a host be controlled?

Answer 6

With drug treatment and vaccination

Question 7

How can wild animals be controlled?

Answer 7

Population control

Vaccination

Question 8

How can vector populations be controlled?

Answer 8

Habitat changes

Pesticides

Question 9

How is anthrax transmitted?

Answer 9

By inhalation of spores or direct animal contact

Question 10

What are the hosts of anthrax?

Answer 10

Cattle
Goat
Sheep

Question 11

How is bovine tuberculosis transmitted?

Answer 11

Through milk

Question 12

What is the main host of bovine tuberculosis?

Answer 12

Cattle

Question 13

What microbe is plague caused by?

Answer 13

Yersinia pestis

Question 14

What are the two main features of yersinia pestis?

Answer 14

Gram negative bacteria

Facultative anaerobic

Question 15

How is plague transmitted?

Answer 15

By fleas

Question 16

In what animals is plague most common?

Answer 16

Wild rodents

Question 17

What does the bacteria of plague do if it is not killed by neutrophils?

Answer 17

Kills macrophages
Multiply
New bacteria released is resistant to neutrophils

Question 18

Where does plague spread within the body and what does it cause?

Answer 18

Through the lymphatic system

Lymph nodes become swollen and hemorrhagic = bubonic plague

Question 19

Where may bacteria spread to in bubonic plague?

Answer 19

The blood = bacteraemia

Question 20

What do the endotoxins released by bubonic plague bacteria result in?

Answer 20

Systemic shock
Liver damage
Respiratory disease

Question 21

When does bubonic plague become pneumonic plague?

Answer 21

When bacteria in the blood infects organs

Question 22

What transmission route does pneumonic plague take when spreading to other animals?

Answer 22

Respiratory

Question 23

What are the treatment drugs for plague?

Answer 23

Streptomyosin

Tetracycline

Question 24

What is the incubation period of plague?

Answer 24

1-7 days

Question 25

What are the two main protozoa that cause malaria?

Answer 25

Plasmodium vivax | Plasmodium falciparum

Question 26

What vector transmits malaria?

Answer 26

Female anopheles mosquito

Question 27

What is the cycle of infection of malaria?

Answer 27

1. Transmission by mosquito bite 2. Sporozoites removed from blood and enter liver 3. Formation of merozoites 4. Merozoites reproduce and infect red blood cells 5. Production of gametes 6. Different mosquito feeds on the same human and is infected 7. Maturation and fertilisation of gametes in new mosquito 8. Growth 9. Development and release of new sporozoites

Question 28

What are the treatments for malaria?

Answer 28

``` Quinine = kills sporozoites Chloroquine = acts within red blood cells Primaquine = acts outside red blood cells ```

Question 29

How can transmission of malaria be controlled?

Answer 29

Eliminate habitats Eliminate mosquito Personal protection

Question 30

Why might some individuals be resistant to malaria?

Answer 30

As a result of polymorphisms | - Altered haemoglobin

Question 31

What type of microbe causes rabies?

Answer 31

RNA virus

Question 32

How is rabies transmitted?

Answer 32

Directly

Question 33

Where does replication of the virus occur?

Answer 33

At the site of inoculation

Question 34

What is the incubation time for rabies?

Answer 34

1 week to 9 months

Question 35

Where does replication of rabies viruses inevitably occur?

Answer 35

In the brain - Hypothalamus - Thalamus

Question 36

What are the non-specific symptoms of rabies?

Answer 36

Malaise Nausea Sore throat Fever

Question 37

What are the neurological symptoms of rabies?

Answer 37

Dilation of pupils Excessive salivation Throat spasms

Question 38

What is the treatment for rabies?

Answer 38

Vaccination after infection | - Inactivated and attenuated

Question 39

What are rickettsia?

Answer 39

Small obligate intracellular bacteria

Question 40

What are the two main groups of rickettsia?

Answer 40

Typhus group | Spotted fever group

Question 41

What is spotted fever?

Answer 41

Necrosis of tissue as a result of rickettsia replicating at the site of a tick bite

Question 42

How do spotted fever bacteria spread?

Answer 42

Systemically and invade endothelial cells of blood vessels causing haemorrhaging and rashing