Haemophilus influenzae

Haemophilus influenzae


Standard Precautions


General Information

  • Fastidious, small aerobic gram-negative coccobacilli
  • Encapsulated (6 types: A-F) or not (non=non-typeable)

Normal respiratory flora (exclusively from humans).

Invasive disease sharply declined after Hib conjugate vaccine widely used, especially in children <5 yrs old who were the main victims.

Most invasive disease is now caused by non-typeable strains.

Colonizer of the upper respiratory tract

NTHi may be cause of mucosal infections:

  • Otitis media
  • COPD exacerbation
  • Sinusitis
  • Conjuctivitis
  • CAP

May cause invasive disease including (Most likely with HIB):

  • Meningitis
  • Pneumonia/empyema
  • Bacteremia
  • Epiglottitis
  • MSK infection
  • Others

Droplet precautions if presentation is epiglottitis (H. influenzae type B HiB).

Hib conjugate vaccine protects against Hib infection but does not protect against Non-typeable strains of H. influenzae or strains A,C,D,E or F.

Vaccine Hib vaccine recommended for patient's with anatomical/functional asplenia (including sickle cell disease), hematopoietic stem cell transplant, cochlear implant, HIV.