This document discusses several species of Haemophilus bacteria. It describes three medically important species - H. influenzae, H. aegyptus, and H. ducreyi. H. influenzae can cause pneumonia, ear infections, and potentially fatal infections like meningitis in children. H. aegyptus causes infectious conjunctivitis epidemics. H. ducreyi is the cause of the sexually transmitted infection chancroid. The document provides details on the morphology, growth requirements, identification testing, and treatment of these Haemophilus species.

1. Haemophilus Spp.
Haemophilus = blood loving

2. Medical Important Species
Haemophilus influenzae.
Haemophilus aegyptus.
Haemophilus ducryi.
less Medical important:-
1) Haemophilus parainfluenzae.
2) Haemophilus. hemolyticus.

3. Haemophilus

4. Normal Habitat:-
 Upper respiratory tract as normal flora.
 The carrier rate in the upper respiratory tract
for H. influenzae type b is 2–4%. The
carrier rate for non-type b H. influenzae is
50–80% or higher.
 The carrier rate for the encapsulated types
A and C to F is low (1–2%).

5. Viability:
 Haemophilus spp. is very
sensitive to cold, can be kill on
refrigerator (4 C).

6. Morphology and Stain:
 Haemophilus spp. is G -Ve rods, or
Cocco bacilli, Pleomorphic
 ( filamentous), Non motile, Non sporing,
and some strain are capsulated.
*Note; long thread and pleomorphic
forms may be seen in CSF (with Pus),
or following culture.

7. Culture Character
 Haemophilus is fastidious, aerobic, and
can grow anaerobic , but better is
aerobic with moist in candle jar with
addition of 10% carbon dioxide, optimal
temperature for growth 35 – 37 C, and
some strain can grow at 30 C or less,
but the incubation period are prolonged.

8.  Type of Culture Media:
 It’s need media contain X and V factors as a
growth requirements factor. This factor can
found in blood agar or Heated blood agar.
 X factor is Porphrin or Haemin ( because X-
dependent Strain are un able to convert
aminolaevulinic acid to protoporphyrin), it’s
used as enzyme respiration, cytochrome.

9. Cont.
 V factor NAD ( Nicotinamide
Adenine Dinucleotide) or it’s
NADP, it’s used as electron carrier
or receptor in oxidation and
reduction.

10. Cont.
 X- factor is heat stable, and V- factor is
heat labile ( 133 C for 30 min ).
 V- factor is release by heating blood
agar medium at 75 ºC in not more than
30 minutes.

11. X & V factor
X factor
V factor
Growth
No growth
No growth
H. influenzae
Growth
No growth
No growth
H. aegyptus
Growth
Growth
No growth
H. ducreyi
Growth
No growth
Growth
H. Parainflunzae

14. Satellitism
 Its used as quick or presumptive method for identify
Haemophilus influenzae.
 It’s perform by use Blood agar medium, the
suspected Haemophilus influenzae is culture by
swabbing in all surface of medium. Then
Staphylococcus aureus inoculated in straight streaking
line. Then incubate in moist Co2 over Night at 37 C.

15. Haemophilus influenzae colonies
near the S.aureus streaking line
is large than far away.

16. Satellitism:

17.  Iridescence:
 When Capsulated strain of Haemophilus
influenzae Cultured on Transparent Medium
such as Levinthal agar, and a beam of White
light directed viewed from the under site the
plate with acute angle, different shades ( Color),
can be seen from red, orange, green, and blue ,
due to optics of capsule layer of Haemophilus
influenzae.

18. Antigenic structure
 According to Capsule structure
Haemophilus influenzae has 6 serotypes
 ( A to F) , the most important is type b
(Hib) .

19. Biotype of H.influnzea:
 H. influnzeae can be divided into 8 Biotypes on
the basis of three biochemical tests:
V111
V11
V1
V
1V
111
11
1
_
+
_
+
_
_
+
+
Indole
Production
_
_
_
_
+
+
+
+
Urease activity
_
_
+
+
+
_
_
+
Ornithine
decarboxylase

20. Biotyping of H.influnzea
 More than 90% of invasive type -b
strain are Biotype 1.

21. Pathogenicity:
 Haemophilus influenzae can causes:-
I. 1- Pyogenic ( Purulent) meningitis ,
specially in kids age 6 months to 2
years.
II. 2- Septicemia and Bacteriaemia.

22. Cont.
I. 3. Epiglottis's ( acute inflammatory
swollen of the epiglottis, and
neighboring structure , this infection is
serious and fatal ,and it can cause air
way destruction, or septicemia ).

23. Cont.
I. 4. Pneumonia.
II. 5. Obits media ( medial ear
infection).
III.6. Cellulites ( Skin infection).

24. Pathogenicity
 Others Haemophilus Sp. occasionally
can causes many infections, but less
severe , it can causes Meningitis,
Endocarditis, and brain abscess.

25. Laboratory diagnosis:
 Specimen:
- CSF for microscope, Culture, and
Biochemistry.
- Blood , Sputum, Throat swab, and Pus &Urine.
* Culture: on blood agar or Chocolate blood
agar in moist atmosphere in addition of Co2
aerobic at 37 C over night.

26. Colonial Morphology
 Colonies are small ( o.5 - 1.5 ul ),
Colorless, Non hemolytic.
 Note: Media Can become selective by
adding Bacitracin ( 300 mg/l ).

27. Colonial Morphology:

28. Biochemical reaction
 Are not used routinely in
identification, but organism ferment
glucose, with acid and gas.
 Other test used Urease, Indole test,
ODC (orinthine decarboxylase ).

29.  The important is to do Serology by
Agglutination test form culture or direct
detection of antigen form CSF.
 Form CSF we detect Antigen either by
Co- agglutination or CCIE (Counter
Current Immuno Electrophoresis ).

30. Quelling Test
 From sample to detect antigen ( Primary
test), depend on Ag – Ab reaction
 ( Capsule swelling ).

31. Treatment
 Drugs used for Haemophilus sp. are:
1. Chloramphenicol (resistance in up to
50% in some regions).
2. Ampicillin.
3. Tetracycline.
4. Co trimaxazole.
* The strain should be test for Beta-
lactamase production.
(35% of strains positive).

32. Cont.
 Best drugs active against almost
100% of strains:
Azithromycin (Macrolide)
Fluoroquinolones
Newer Cephalosporin

33. Prevention of meningitis
With antibiotic resistance increasing
it is important to prevent infections
before they start
1980s capsule vaccine was not
effective
Kids < 2 years old don’t make
antibodies to sugars

34. Cont.
Haemophilus aegyptius

35. General Properties
 Not occurring as a common
commensally in the nasopharyngeal
of health subject.
 Grow more slowly than H.influnzea.
 Failure to ferment D- xylose, and
showing stronger Haemagglutination
activity with human or guinea Pig red
blood cells

36. Pathogenicity:
 Haemophilus aegyptius This
organism was formerly called the
Koch-Weeks bacillus; can causes
acute and infectious Conjunctivitis (
Pink eye) and this infection is
epidemic.

37. Cont.
1990s scientist conjugated capsule
sugar to a protein.
Children under 2 year can
produce antibody to proteins.
Also make antibody to the sugar
attached to a protein.

38. Cont.
Started to vaccinate as young as 2
months old
Hib meningitis in children almost
eradicated.

39. Cont.
 Chancroid:- Small inflammatory
Papules ,develop surround by a
narrow erythematous zone.

41. Haemophilus ducreyi
 The small gram-negative rods occur in
strands in the lesions, usually in
association with other Pyogenic
microorganisms. H ducreyi requires X
factor but not V factor.

42. Cont.
 It is grown best from scrapings of the
ulcer base on chocolate agar containing
1% Iso Vitale X and 3ug/ml vancomycin,
3 g/mL, and incubated in 10% CO2 at 33
°C in humidity for up to 5 days .
 Colonies is small 1 – 2 mm , yellowish,
and difficult to emulsify.

43. Pathogenicity
 Haemophilus ducreyi cause Veneral
disease called Chancroid or Soft sore,
it’s Painful sore in genital organ , it’s
has no hardening or red area.
 ( not spirochetes).

44. Cont.
There is no permanent immunity
following Chancroid infection.
 Treatment:
with intramuscular: Ceftriaxone,
oral Trimethoprim- Sulfamethoxazole,
or oral Erythromycin.