Genotypic and Phenotypic Characteristics of Moraxella catarrhalis from Patients and Healthy Asymptomatic Participants among Preschool Children

• Published in: Pathogens (Basel) Vol. 11; no. 9; p. 984
• Main Authors: Zhao, Na, Ren, Hongyu, Deng, Jianping, Du, Yinju, Li, Qun, Zhou, Pu, Zhou, Haijian, Jiang, Xiangkun, Qin, Tian
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 29.08.2022; MDPI
• Subjects: Age; Antibiotic resistance; Antibiotics; Antimicrobial agents; antimicrobial susceptibility; Asymptomatic; Azithromycin; Cefuroxime; Children; Cloning; Disease; Drug resistance; Epidemics; Epidemiology; Erythromycin; Lipooligosaccharides; Middle ear; Moraxella catarrhalis; multilocus sequence typing; Otitis media; Patients; Pneumonia; Preschool children; Respiratory tract; Serotypes; Strains (organisms); Streptococcus infections; Vaccines; Vigilance; Viral infections; Virulence; China
• ISSN: 2076-0817; 2076-0817
• DOI: 10.3390/pathogens11090984

(1) Background: M. catarrhalis can ascend into the middle ear, where it is a prevalent causative agent of otitis media in children, or enter the lower respiratory tract, where it is associated with community-acquired pneumonia (CAP). In this study, we aimed to provide an overview of the prevalence of M. catarrhalis in preschool children. (2) Methods: M. catarrhalis strains were isolated from samples. All isolates were characterized in terms of serotypes (STs), virulence genes, multilocus sequence type, and antibiotic susceptibility. (3) Results: The percentages of strains expressing lipooligosaccharides (LOSs), serotype A, B, C, or unknown were 67.61%, 15.71%, 4.28%, and 12.38%, respectively. Among the strains, 185 (88.10%) carried ompB2, 207 (98.57%) carried ompE, and 151 (71.90%) carried ompCD. The most frequently identified STs were ST449 (n = 13), ST64 (n = 11), and ST215 (n = 10). The resistance rates to the antibiotics cefuroxime, azithromycin, and erythromycin were 43.33%, 28.10%, and 39.05%, respectively. (4) Conclusions: High prevalence of some-specific ST types and high rates of antibiotic resistance indicate the necessity for an increased vigilance of resistant strains, a rational use of antibiotics in preschool children, and most importantly, the surveillance of healthy asymptomatic participants preschool children with M. catarrhalis. Our findings provide a platform for the development of novel M. catarrhalis vaccines.