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Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
Published on: September 5, 2013
EMM types of Streptococcus pyogenes in Chennai
T Menon1, A M Whatmore, S Srivani
1Department of Microbiology, Dr ALM PGIBMS, University of Madras, Chennai, India.
Indian Journal of Medical Microbiology
|August 1, 2007
Summary
Group A Streptococcus (GAS) M protein typing is shifting to emm gene sequencing. This study identifies prevalent emm types in South India, finding a diverse distribution among clinical isolates.
Area of Science:
- Microbiology
- Molecular Epidemiology
- Infectious Diseases
Background:
- The M protein of Group A Streptococcus (GAS) is a key virulence factor.
- Traditional serologic M typing is being superseded by molecular methods like emm gene sequencing.
- Understanding the distribution of emm types is crucial for epidemiology and vaccine development.
Purpose of the Study:
- To report the prevalent emm types of Group A Streptococcus (GAS) in South India for the first time.
- To characterize the molecular epidemiology of GAS in this region.
- To provide baseline data for future public health interventions.
Main Methods:
- Clinical isolates of GAS were collected.
- emm gene sequencing was performed to determine M types.
- Sequence data was analyzed to identify prevalent types and their distribution.
Main Results:
- A diverse range of emm types were identified among the clinical isolates.
- No single emm sequence showed a marked preponderance.
- Eleven different emm sequences were found in 34 analyzed isolates.
Conclusions:
- emm gene sequencing is a viable alternative for M typing in South India.
- GAS isolates in South India exhibit a varied emm type distribution.
- Further surveillance is needed to monitor GAS epidemiology in the region.
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