Hypervirulent Clone of Group B Streptococcus Serotype III Sequence Type 283, Hong Kong, 1993-2012
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Abstract:
We describe a hypervirulent clone of group B Streptococcus serotype III, subtype 4, sequence type 283, that caused invasive disease with a predilection for meningitis in Hong Kong during 1993-2012. The organism is associated with high mortality and increased summer prevalence and is linked to diseased fish from freshwater fish farms.
Insights
A hypervirulent group B Streptococcus clone caused invasive meningitis in Hong Kong, leading to high mortality. This strain, linked to diseased fish, showed increased prevalence during summer months.
Area of Science:
- Microbiology
- Epidemiology
- Infectious Diseases
Background:
- Group B Streptococcus (GBS) is a leading cause of invasive bacterial infections in neonates and adults.
- Specific clones of GBS can exhibit hypervirulence and distinct epidemiological characteristics.
- Understanding GBS epidemiology is crucial for public health interventions.
Purpose of the Study:
- To characterize a hypervirulent clone of GBS serotype III, subtype 4, sequence type 283.
- To investigate the clinical presentation, mortality, and seasonality of invasive disease caused by this clone in Hong Kong.
- To explore potential environmental links, such as diseased fish, associated with the clone.
Main Methods:
- Molecular typing (serotyping, multilocus sequence typing) to identify the GBS clone.
- Retrospective analysis of invasive GBS isolates from Hong Kong (1993-2012).
- Clinical data review to assess disease patterns, including meningitis and mortality.
Main Results:
- Identification of a hypervirulent GBS clone (serotype III, subtype 4, ST-283) responsible for invasive disease.
- The clone demonstrated a predilection for causing meningitis.
- High mortality rates were associated with infections caused by this clone, with increased prevalence observed during summer.
- A link was established between this clone and diseased fish from freshwater fish farms.
Conclusions:
- A specific hypervirulent GBS clone (ST-283) emerged as a significant cause of invasive meningitis in Hong Kong.
- The clone's association with diseased fish suggests a potential zoonotic transmission route.
- The findings highlight the importance of monitoring GBS strains and potential environmental sources for public health surveillance.
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