Role of biofilm formation in the persistent colonization of Haemophilus influenzae in children from northern India.
The human nasopharynx is a major ecological niche for Haemophilus influenzae colonization. Establishment of infection is critically dependent on the persistence of bacteria in the nasopharynx. Various factors are presumed to mediate this persistence and the influence of biofilm formation has been under scrutiny for a long time. In a prospective population-based study, the nasopharyngeal colonization pattern of 250 children <2 years old was traced to gain further insights into the phenomenon. The association between biofilm formation and persistence was delineated by quantitative biofilm assay, while the true nature of biofilm formers was further evaluated by electron microscopy studies. H. influenzae isolates obtained in this study, when analysed by phenotypic and genotypic means, revealed a clonal distribution of strains within the population. The biofilm formation ability of the isolates was found to be significantly associated with bacterial persistence (P<0.001). The isolates having biofilm formation ability were found to be 7.1 times more likely to persist in the nasopharynx than non-biofilm formers. This study provides direct evidence indicating the intricate relationship between biofilm formation and the persistence of bacteria. Our results emphasize the need to evaluate the potential for biofilm formation before designing preventive and therapeutic strategies.
Sekhar
Sasanka
S
School of Public Health, Postgraduate Institute of Medical Education and Research, Chandigarh, India.|Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Kumar
Rajesh
R
School of Public Health, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Chakraborti
Anuradha
A
Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
D018441:Biofilms / Q000254:growth & development*; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D002675:Child, Preschool; D006192:Haemophilus Infections / Q000453:epidemiology* / Q000382:microbiology; D006193:Haemophilus influenzae / Q000145:classification / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification; D006801:Humans; D007194:India / Q000453:epidemiology; D007223:Infant; D008855:Microscopy, Electron, Scanning; D009305:Nasopharynx / Q000382:microbiology*; D019105:Random Amplified Polymorphic DNA Technique