Prevalence of β-lactamase-negative ampicillin-resistant haemophilus influenzae isolated from patients of a teaching hospital in Thailand.

The aim of this study was to investigate the prevalence of β-lactamase-negative ampicillin-resistant (BLNAR) Haemophilus influenzae isolated from patients of a teaching hospital in Thailand. Eighty-eight isolates of H. influenzae were collected between September 2005 and March 2008.