THE INTERACTION OF HOST AND BACTERIUM IN THE DEVELOPMENT OF COMMUNICABILITY BY STREPTOCOCCUS HAEMOLYTICUS
1Department of Medicine, College of Physicians and Surgeons, Columbia University, the Presbyterian Hospital, and Babies Hospital, New York.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Group A Streptococcus haemolyticus type 12 caused an epidemic. Some children acted as disseminating hosts, developing pathogen communicability and adaptability, while nurses did not spread contagion.
Area of Science:
- Microbiology
- Epidemiology
- Infectious Diseases
Background:
- An epidemic of Group A Streptococcus haemolyticus type 12 infections occurred, involving infants, children, and nurses.
- Transmission dynamics differed between children and nurses, with some children acting as key disseminators.
Purpose of the Study:
- To investigate the factors contributing to the communicability of Group A Streptococcus haemolyticus type 12 during an epidemic.
- To understand the role of host-pathogen interactions in the development of bacterial communicability.
Main Methods:
- Observational study of an epidemic involving clinical case identification and microbiological analysis of throat flora.
- In vitro cultivation and characterization of Streptococcus strains isolated from infected individuals.
Main Results:
- Children who spread contagion had low levels of recognizable type 12 organisms, unlike nurses.
- Some children harbored non-hemolytic streptococci that became hemolytic type 12 upon cultivation.
- Isolated hemolytic type 12 streptococci became non-hemolytic in serum-containing media, indicating lability.
Conclusions:
- Infants and children can act as disseminating hosts, fostering pathogen communicability and adaptability.
- Bacterial communicability arises from host factors allowing microbial lability and bacterial adaptations for survival and colonization.
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