1. بسم الله الرحمن الرحيم GENUS: HAEMOPHILUS Prof. Khalifa Sifaw Ghenghesh

2. Small, Pleomorphic G-ve Rods Require Growth Factors – – Two factors > X & V – – X = haemin – – V = Nicotinamide adenine dinucleotide (NAD) = NAD phosphate (NADP) BA Chocolate agar

3. Species Growth Factor Required ---------------------------------------------- H. influenzaeX + V H. parainfluenzae V H. ophrophilus X H. ducreyi X ----------------------------------------------

4. Haemophilus influenzae Smooth and rough colonies occur Smooth and rough colonies occur Capsulated >> Capsulated >> Non-capsulated >> Non-capsulated >>

5. ANTIGENIC STRUCTURE 1. The capsular polysaccharide antigens: 6 serotypes: a - f. Encapsulated H. influenzae >> Quellung (capsular swelling) reaction. 2. Somatic antigens:

6. VIRULENCE FACTORS i. Capsule: i. Capsule: ii. Outer membrane components: ii. Outer membrane components: OMP & LOS OMP & LOS iii. Adherence: iii. Adherence: iv. IgA proteases: iv. IgA proteases:

7. PATHOGENESIS Normal Carriage – – H. influenzae > Human parasite – – Non-capsulate HI > nasopharynx or throat of 25-80% of healthy people – – Capsulate strains in 5-10% – – Immunization with conjugate vaccine > Invasive infections Non-Invasive Disease

8. INVASIVE INFECTIONS H. Influenzae type b Respiratory portal of entery (Inhalation) Colonization of nasopharynx Penetration of submucosa Invasion of Bloodstream Meningitis, Epiglottitis, Bacteraemia Pneumonia, Septic arthritis Non-Capsulate HI: > Meningitis and Septicaemia > the Neonate

9. NON-INVASIVE DISEASE Local Infections: – – Physiological or Anatomical Abnormalities – – Otitis Media, Sinusitis – – Purulent episodes > patients with exacerbations of chronic obstructive airway disease – – Non-capsulate strains of HI – – Viral Infections ?

10. LABORATORY DIAGNOSIS 1. Direct examination: – –Specimen: CSF, middle ear aspirate, sputum (purulent). 2. Culture: – – Chocolate agar + CO 2 – –Blood culture bottles – –Antigenic detection – –Molecular Techniques

11. Blood agar plate culture of Haemophilus influenzae

12. Haemophilus influenzae satelliting around Staphylococcus aureus

13. TREATMENT - Systemic illness - Systemic illness – 3 rd Generation cephalosporins – TMP-SMZ, Ciprofloxacin, Clarithromycin - Otitis media in children - Otitis media in children - Pneumonia in adults - Pneumonia in adults - Acute sinusitis - Acute sinusitis – Amoxicillin, Augmentin, Clarithromycin, PREVENTION Vaccination Vaccination

14. Haemophilus influenzae biogroup aegyptius (Haemophilus aegyptius) Haemophilus influenzae biogroup aegyptius (Haemophilus aegyptius) – Epidemic conjunctivitis –Brazillian purpuric fever Haemophilus ducreyi> Chancroid Haemophilus ducreyi> Chancroid Haemophilus parainfluenzae Haemophilus parainfluenzae