Related Experiment Video

Updated: Jun 5, 2026

Culture Methods to Determine the Limit of Detection and Survival in Transport Media of Campylobacter Jejuni in Human Fecal Specimens
08:23

Culture Methods to Determine the Limit of Detection and Survival in Transport Media of Campylobacter Jejuni in Human Fecal Specimens

Published on: March 10, 2020

Polyclonal dissemination of tetracycline resistance among Streptococcus pyogenes paediatric isolates from Brazil

Pierre Robert Smeesters1, Sabina Cadar, Pierre-Alexandre Drèze

  • 1Institut de Biologie et de Médecine Moléculaires, Faculté des Sciences, Université Libre de Bruxelles, Belgium. psmeeste@ulb.ac.be

Journal of Infection in Developing Countries
|January 22, 2011
PubMed

Insights

Group A Streptococcus (GAS) in Brazil shows high tetracycline resistance due to polyclonal spread of resistant strains. Penicillin and macrolide resistance were not observed in this study.

Area of Science:

  • Microbiology
  • Epidemiology
  • Infectious Diseases

Background:

  • Limited data exists on antibiotic resistance patterns of Group A Streptococcus (GAS) in South America.
  • Understanding GAS antibiotic resistance is crucial for effective treatment and public health strategies.

Purpose of the Study:

  • To analyze the antibiotic susceptibility patterns of GAS isolates from children in central Brazil.
  • To investigate the prevalence and genetic basis of antibiotic resistance in GAS.

Main Methods:

  • Prospective epidemiological study design.
  • Analysis of antibiotic susceptibility testing for GAS isolates.
  • Detection of resistance genes, including tetM.
  • Phylogenetic analysis of emm-types.

Main Results:

  • No GAS isolates exhibited resistance to penicillin or macrolides.
  • Sixty-one percent of GAS isolates were highly resistant to tetracycline, with 85% harboring the tetM gene.
  • Ninety-five percent of tetracycline-resistant isolates were also resistant to minocycline.
  • Tetracycline resistance was associated with 30 different emm-types and arose independently.

Conclusions:

  • A high prevalence of tetracycline resistance in GAS was identified in central Brazil.
  • Polyclonal dissemination of tetracycline-resistant emm-types contributes to the observed resistance.
  • The findings highlight the need for ongoing surveillance of GAS antibiotic resistance in the region.
Abstract

More Related Videos

Assessment of Intestinal Transcytosis of Neonatal Escherichia coli Bacteremia Isolates08:32

Assessment of Intestinal Transcytosis of Neonatal Escherichia coli Bacteremia Isolates

Published on: February 17, 2023

Related Concept Videos

Mechanism of Antibiotic Resistance in MRSA01:25

Mechanism of Antibiotic Resistance in MRSA

Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...
Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
Streptococcal Pharyngitis01:27

Streptococcal Pharyngitis

Streptococcal pharyngitis, commonly known as “strep throat,” is an acute infection of the oropharyngeal tissues caused by the Gram‑positive Group A Streptococcus (Streptococcus pyogenes). Transmission occurs primarily through respiratory droplets expelled during coughing, sneezing, or talking.Mechanisms of Host Entry and Immune EvasionUpon entering the host, S. pyogenes adheres to the mucosal epithelial cells of the pharynx via surface proteins, notably lipoteichoic acid and the antiphagocytic...
Development of Antibiotic Resistance01:30

Development of Antibiotic Resistance

Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...