Molecular heterogeneity among north Indian isolates of Group A Streptococcus

Sagar, Vivek; Bakshi, Dapinder Kaur; Nandi, Sobhan; Ganguly, Nirmal Kumar; Kumar, Rajesh; Chakraborti, Anuradha

doi:10.1111/j.1472-765x.2004.01545.x

Cited by 31 publications

(27 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since then, many reference and research laboratories have now embraced emm gene sequencing, and various studies have been published (2,4,6,14,17). The strep-EURO project has strengthened links between centers and has established a network of European streptococcal reference centers.…”

Section: Discussionmentioning

confidence: 99%

International Quality Assurance Study for Characterization ofStreptococcus pyogenes

Neal¹,

Beall

Ekelund

et al. 2007

J Clin Microbiol

View full text Add to dashboard Cite

Surveillance of group A streptococcal (GAS) infections was undertaken as a major component of the European Commission-funded project on severe GAS disease in Europe (strep-EURO). One aim of strep-EURO was to improve the quality of GAS characterization by standardization of methods. An external quality assurance study (EQA) was therefore carried out to evaluate current global performance. Eleven strep-EURO and seven other streptococcal reference centers received a panel of 20 coded GAS isolates for typing. Conventional phenotypic typing (based on cell surface T and M protein antigens and opacity factor [OF] production) and molecular methods (emm gene typing) were used either as single or combined approaches to GAS typing. T typing was performed by 16 centers; 12 centers found one or more of the 20 strains nontypeable (typeability, 89%), and 11 centers reported at least one incorrect result (concordance, 93%). The 10 centers that tested for OF production achieved 96% concordance. Limited availability of antisera resulted in poor typeability values from the four centers that performed phenotypic M typing (41%), three of which also performed anti-OF typing (typeability, 63%); however, concordance was high for both M (100%) and anti-OF (94%) typing. In contrast, the 15 centers that performed emm gene sequencing achieved excellent typeability (97%) and concordance (98%), although comparison of the performance between centers yielded typeability rates from 65 to 100% and concordance values from 83 to 100%. With the rapid expansion and use of molecular genotypic methods to characterize GAS, continuation of EQA is essential in order to achieve international standardization and comparison of type distributions.

show abstract

Section: Discussionmentioning

confidence: 99%

International Quality Assurance Study for Characterization ofStreptococcus pyogenes

Neal¹,

Beall

Ekelund

et al. 2007

J Clin Microbiol

View full text Add to dashboard Cite

show abstract

“…Hu et al included 26 different M types in a multiple epitope formulation [19], which has been predicted to provide protection against 85%-90% of M types in the United States and Europe. In contrast to the United States and Europe, Asian countries show marked diversity of emm genotypes [20,21]. Countries such as India, Brazil, Nepal, and Australia are unlikely to benefit from the 26-valent vaccine because of this diversity [22].…”

Section: Discussionmentioning

confidence: 99%

Clinical and molecular epidemiology of beta-hemolytic streptococcal infections in India

Mathur

Bhardwaj

Mathur

et al. 2014

J Infect Dev Ctries

View full text Add to dashboard Cite

Introduction: Beta-hemolytic streptococci (βHS) cause a diverse array of human infections. Despite the high number of cases of streptococcal carriers and diseases, studies discerning the molecular epidemiology of βHS in India are limited. This study reports the molecular and clinical epidemiology of beta-hemolytic streptococcal infections from two geographically distinct regions of India. Methodology: A total of 186 isolates of βHS from north and south India were included. The isolates were identified to species level and subjected to antimicrobial susceptibility testing. Polymerase chain reaction (PCR) was done to detect exotoxin genes, and emm types of group A streptococci (GAS) strains were ascertained by sequencing. Results: GAS was the most common isolate (71.5%), followed by group G streptococci (GGS) (21%). A large proportion of GAS produced speB (97%), smeZ (89%), speF (91%), and speG (84%). SmeZ was produced by 21% and 50% of GGS and GGS, respectively. A total of 45 different emm types/subtypes were seen in GAS, with emm 11 being the most common. Resistance to tetracycline (73%) and erythromycin (34.5%) was commonly seen in GAS. Conclusions: A high diversity of emm types was seen in Indian GAS isolates with high macrolide and tetracycline resistance. SpeA was less commonly seen in Indian GAS isolates. There was no association between disease severity and exotoxin gene production.

show abstract

“…For DRS, only a few alleles have been described thus far (4). Recently, information regarding heterogeneous emm type prevalence in India has been reported (6,12,13), but there are no data on the virulence status of GAS from this region. Here we report the distribution of the drs gene among Indian isolates and describe the sequence heterogeneity.…”

mentioning

confidence: 99%

DRS Is Far Less Divergent than Streptococcal Inhibitor of Complement of Group A Streptococcus

Sagar¹,

Kumar

Ganguly

et al. 2007

J Bacteriol

View full text Add to dashboard Cite

show abstract

Molecular heterogeneity among north Indian isolates of Group A Streptococcus

Cited by 31 publications

References 23 publications

International Quality Assurance Study for Characterization ofStreptococcus pyogenes

International Quality Assurance Study for Characterization ofStreptococcus pyogenes

Clinical and molecular epidemiology of beta-hemolytic streptococcal infections in India

DRS Is Far Less Divergent than Streptococcal Inhibitor of Complement of Group A Streptococcus

Contact Info

Product

Resources

About