A 5-year surveillance study of 44,691 isolates of Haemophilus influenzae project Beta-Alert 1993-1997.

Beta-Alert is a surveillance program developed in 1993 to monitor the percentage of beta-lactamase-producing Haemophilus influenzae isolates obtained from specimens submitted to regional commercial laboratories. The results of this study demonstrate that levels of beta-lactamase producers have remained between 31 and 38% in the United States over the past 5 years.