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Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria
Published on: February 23, 2014
Evolving microbes and re-emerging streptococcal disease
1Laboratory of Human Bacterial Pathogenesis, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Building 16, Room 202, 16 Center Drive, MSC 6705, Bethesda, MD 20892, USA. richard_krause@nih.gov
Clinics in Laboratory Medicine
|December 20, 2002
Summary
Microbial evolution drives future epidemics. Understanding microbial virulence factors and host-microbe genetics is crucial for confronting emerging infectious diseases.
Area of Science:
- Evolutionary biology
- Microbiology
- Genetics
Background:
- Microbes evolve rapidly, posing continuous threats through emerging epidemics.
- Historical pandemics, like scarlet fever, offer insights into microbial evolution and virulence.
- Streptococcus pyogenes (GAS) has evolved, with current strains potentially possessing historical pandemic virulence factors.
Purpose of the Study:
- To analyze the evolutionary dynamics of microbes and their impact on epidemic patterns.
- To investigate the potential link between historical pandemic scarlet fever and current Group A Streptococcus (GAS) strains causing Streptococcal Toxic Shock Syndrome (STSS).
- To examine the virulence properties of GAS strains from recent outbreaks in relation to historical strains.
Main Methods:
- Review of historical epidemic data, focusing on the 19th-century scarlet fever pandemic.
- Comparative analysis of microbial genetics and virulence factors between historical and contemporary GAS strains.
- Population genetics and evolutionary analysis of host-microbe relationships.
Main Results:
- Microbes exhibit rapid evolution, outpacing human adaptation and research.
- Contemporary GAS strains linked to Streptococcal Acute Rheumatic Fever (ARF) outbreaks display virulence traits similar to early 20th-century strains.
- Evidence suggests current GAS strains causing STSS may share virulence factors with pandemic scarlet fever-causing GAS.
Conclusions:
- The continuous evolution of microbes necessitates a comprehensive, multi-faceted approach to studying infectious diseases.
- Understanding microbial evolution and virulence is key to predicting and managing future epidemics.
- Studying infectious diseases from all perspectives is essential for societal protection against microbial threats.
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