Study on serotype and the resistance of haemophilus influenzae from children with respiratory tract infection in Guangzhou.

Objective This study was designed to dynamically investigate resistance and serotyping of Haemophilus influenzae (Hi) isolated from children’s respiratory tract during 2000—2007. Methods The specimens of sputum and swabes from children with acute respiratory tract infection were collected and incubated on improved Collumbia chocolate medium. Totally 381 Hi strains isolated during 2000—2003 were serotyped by Haemophilus Influenzae Antiserum. Results The prevalence of β- lactamase was 30.75% in all Hi isolates. Hib and NTHi were 1.57% and 95.53% among 381 Hi strains isolated during 2000—2003. The Hi isolates were slightly resistant to amoxicillin-clavulanic , ceftriaxone, cefaclor,and cefuroxime, the resistant rate to ampicillin and chloramphenicol being 12.61%～41.60% and 10.81%～21.11% respectively. About 13.51%～44.24% of Hi isolates were resistant to tetracycline and 41.20% ～72.13% resistant to trimethoprim-sulfamethoxazole. Conclusion NTHi is the major serotype of Hi in children with acute respiratory tract infection . The prevalence of Hib is low. The resistant rate to ampicillin, chloramphenicol, tetracycline and trimethoprim-sulfamethoxazole are increasing. The use of β-lactamase is the first choice in the treatment of infections caused by Hi.