Severe Vaccine Preventable Bacterial Infections Of The Upper Respiratory Trac

Question 1

Exotoxin

Answer 1

also just called ‘toxin’. Produced and secreted by bacteria with
toxic effect on host

Question 2

Endotoxin

Answer 2

Part of the outer membrane of Gram-negative bacilli, released.
in severe infection, responsible for severe effects.

Question 3

Bacterial exotoxin that has been modified by chemical or
other treatment so that it is no longer toxic but retains
immunogenic properties

Answer 3

toxoid

Question 4

what causes Diptheria

Answer 4

corynebacterium diphtheriae

+ cocci

Question 5

Toxins are actually encoded by?

Answer 5

bacteriophage - virus of bacteria

Question 6

explain the pathogenesis of Diphtheria

Answer 6

Bacteria adhere to epithelium via pili
* Local superficial growth and replication of bacteria (doesn’t invade deeper into body)
* Toxin destroys cells forming an ulcer covered with necrotic cells- the necrotic layer is called a ‘
false membrane’
* With extensive inflammation and swelling of surrounding tissues and lymph nodes
* Can cause obstruction of respiratory tract depending on location, especially narrow areas like
larynx
* Toxin is also absorbed sy

Question 7

Diphtheria: Prevention

Answer 7

Spread from person to person by droplet spread from upper respiratory tract, or by direct contact
* At risk: unvaccinated or incompletely vaccinated, including older adults with waning immunity
* In unvaccinated population affects mainly pre-school children
* In partially vaccinated population affects mainly older children, teenagers and even adults

Question 8

what do vaccine contain ?

Answer 8

Diphtheria toxoid

vaccine preventable

Question 9

Diphtheria: Treatment

Answer 9

Treatment
* Anti-toxin to neutralise unbound toxin
* Antibiotics to reduce infectivity and prevent spread
* Airway support
* Contacts who have been exposed to a case need to be tested, and given antibiotics and vaccin

Question 10

Whooping Cough

Answer 10

Severe childhood respiratory infection
* Typically starts as mild upper respiratory tract infection (like common cold), but then some
days later get episodes of persistent coughing (paroxysms) followed by an inspiratory
‘whooping’ sound or sometimes by vomiting
* This paroxysmal stage can last 1-2 months or mor

Question 11

what causes whooping cough

Answer 11

Bordetella pertussis
Gram negative coccobacillus
* Infects ciliated mucosal cells of upper airway, then produces a variety of toxic factors that
influence disease process

Question 12

The correct medical term for whooping cough is ?

Answer 12

pertussis

Question 13

Pertussis: Complications

Answer 13

• Anoxia leading to central nervous system complications including seizures and brain
  damage
• Exhaustion
• Malnutrition
• Trauma due to coughing- subconjunctival haemorrhage, pneumothorax, etc
• Secondary bacterial infection * Long lasting lung damage; see later lecture on bronchiectasis

Question 14

how to prevent pertussis

Answer 14

use acellular vaccine containing various different purified pertussis antigens

Question 15

Pertussis: Treatment

Answer 15

Supportive care
* Oxygen, fluids, nutrition
* Antibiotics
* To reduce infectivity and further spread
* Probably doesn’t influence course of disease much once already in paroxysmal
phase
* Treatment of

Question 16

: a flap of tissue that sits beneath the tongue at the back of the throat??//????

Answer 16

Epiglottis

Question 17

Infection of the epiglottis causes swelling of epiglottis and pain with difficulty in what?

Answer 17

swallowing and breathing.

Question 18

what causes epiglottitis

Answer 18

due to haemophilus influenza subtype B

Question 19

what is used to be caused by H. influenza B

Answer 19

Used to cause meningitis, bacteremia, arthritis and other infections especially in young
children

Question 20

Epiglottitis due to Haemophilus influenzae type B: Prevention

Answer 20

vaccine H. influenza type B vaccine conjugate.