Each of the following statements concerning certain gram-negative rods is correct EXCEPT:

  •  Legionella pneumophila infection is acquired by inhalation of aerosols from environmental water sources.
  •  Pseudomonas aeruginosa causes wound infections that are characterized by blue-green pus as a result of pyocyanin production.
  •  Whooping cough, which is caused by Bordetella pertussis, is on the rise because changing antigenicity of the organism has made the vaccine relatively ineffective.
  •  In unimmunized individuals, invasive disease caused by Haemophilus influenzae is most often due to strains possessing a type b polysaccharide capsule.