Morphology
i)
shape – it is usually thich oval rrod . Pleomorphism
may be found . threads may appear in old culture .
ii)
Size – It is about 1.2 μ in length and 0.3 μ in breadth
.
iii)
It is gram negative bacillus .
iv)
It is non sporing
v)
It is non flagellated so non motile
vi)
Capsule is present but cannot be easily detected .
Pathogenesis of Haemophilus pertusis or Bordet- gengou
Bacillus
i)
1..it will produce whooping cough in children and it
may be transmitted by direct contact or by droplet infection
ii)
2.. The incubation period is from a few days to a fort
night .
iii)
The lesions are found in the mucous membrane of the
upper respiratory tract . There will be hypereaemia and catarrhal inflammation
in the mucosa . the cilia of the trachea become clogged and destroyed by the
organism and mucous . The collection of the mucous will be expelled by the
paroxysm of coughing .
iv)
The onset of the disease is characterised by cough ,
anorexia and general malaise .
v)
The cough at first will be dry and short . But a few
days after , it becomes paroxysmal followed by vomiting . A typical whoop will
oproduce at the time of paroxysm . This stage may last for several weeks . The
patient may recover completely or some
complication may rise .
vi)
The complications are ---
a) Broncopneumonia
b) Bronchitis
c) Convulsion
d) Pinpoint
haemorrhage in the cerebrum , central nerous system and in the conjubnctiva
e) Prolapse
rectum
f)
Hernia .
