GRoup A StrePtococcus (GRASP)

Gene Expression in Isolates of Group A Streptococci Recovered From Patients Who Are Carriers

The purpose of the research is to help understand why some children become carriers of strep and whether children who are carriers need to be treated with antibiotics.

Study Overview

• Status: Recruiting
• Conditions: Streptococcal Pharyngitis
• Intervention / Treatment: Other: Identifying group A strep carriers

Detailed Description

The overall objective of this investigation is to understand the differences in Group A streptococci in children who are acutely infected from those who are carriers. The hypothesis is that when in the carrier state, GAS exhibits unique transcriptional profiles that differ from those of the acute infection state. The investigators expect transcriptional profiles of GAS to provide important information regarding the changes the organism undergoes when transitioning between acute infection and carriage.

The specific aims of this study are:

1. To collect longitudinal participant-samples from acute and carriage phases of GAS infection and compare transcriptomic profiles and whole genome sequences of GAS recovered from acute and carrier pharyngeal swabs obtained from the same participants.
2. To evaluate how identified differentially expressed genes, or observed genetic polymorphisms, influence GAS models of bacterial colonization and pathogenesis.

To do this, the investigators will to identify 12 children with acute pharyngitis due to Group A streptococcus (GAS) who are pharyngeal carriers of GAS. Thirty percent of children 4 to 16 years of age with acute pharyngitis occurring between October and May will have a positive culture or rapid antigen detection test for GAS. Approximately 8-10% of these children with pharyngitis and a positive culture or rapid antigen detection test (RADT) for GAS will be carriers. Therefore,180 participants will need to be enrolled.

• Study Type: Observational
• Enrollment (Estimated): 180

Contacts and Locations

• Study Contact: Name: Cherie Schommer, BA; Phone Number: 608-262-2631; Email: schommer2@wisc.edu

Study Locations

• United States
  • Wisconsin
    • Madison, Wisconsin, United States, 53717
      • Recruiting
      • UW Health Pediatric Clinics
      • Principal Investigator: Gregory DeMuri, MD
      • Sub-Investigator: Ellen R Wald, MD
      • Contact: Bridget Johnson, BAN,RN,CCRC; Phone Number: 608-264-1400; Email: bridget.johnson@pediatrics.wisc.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 5 years to 15 years (Child)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Children will be eligible for this study if they are ages 5 to 15 years and have been diagnosed to have acute pharyngitis caused by GAS (with a positive rapid antigen detection test (RADT). Children will be excluded if they are unable to take beta lactam antibiotics. Children will be enrolled at UW Health sites in Madison, Wisconsin, including both pediatric ambulatory care clinics and urgent care clinics. The study team will offer participants the option to complete follow-up study visits in-clinic

Description

Inclusion Criteria:

• Children ages 5-15 years
• Positive rapid antigen detection test for group A streptococcus
• Parent or legal guardian present and able to provide consent
• Provider prescribes treatment with a beta lactam antibiotic
• English speaking

Exclusion Criteria:

• Unable to take beta lactam antibiotics
• Other concurrent bacterial infection, i.e., pneumonia

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Rapid Strep Positive; Children will be eligible for this study if they are ages 5 to 15 years and have been diagnosed to have acute pharyngitis caused by GAS with a positive Rapid Antigen Detection Test (RADT).	Other: Identifying group A strep carriers; At study entry, at 14 days, and if follow up is positive, again in 14-21 days: Standard culture for GAS and analysis of mRNA.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Identifying children who are pharyngeal carriers of Group A streptococcus	The specific aim of this study is to identify 30 children with acute pharyngitis due to Group A streptococcus (GAS) and 30 children who are pharyngeal carriers of GAS. Thirty percent of children 4 to 16 years of age with acute pharyngitis occurring between October and May will have a positive culture or rapid antigen detection test for GAS. Approximately 10-15% of these children with pharyngitis and a positive culture or rapid antigen detection test (RADT) for GAS will be carriers	2 weeks

Collaborators and Investigators

• Sponsor: University of Wisconsin, Madison
• Collaborators: National Institute of Allergy and Infectious Diseases (NIAID)
• Investigators: Principal Investigator: Gregory DeMuri, MD, University of Wisconsin, Madison

Publications and helpful links

General Publications

• Bisno AL. Acute pharyngitis. N Engl J Med. 2001 Jan 18;344(3):205-11. doi: 10.1056/NEJM200101183440308.
• Carapetis JR, Steer AC, Mulholland EK, Weber M. The global burden of group A streptococcal diseases. Lancet Infect Dis. 2005 Nov;5(11):685-94. doi: 10.1016/S1473-3099(05)70267-X.
• Musser JM, Shelburne SA 3rd. A decade of molecular pathogenomic analysis of group A Streptococcus. J Clin Invest. 2009 Sep;119(9):2455-63. doi: 10.1172/JCI38095.
• Pichichero ME. Group A beta-hemolytic streptococcal infections. Pediatr Rev. 1998 Sep;19(9):291-302. doi: 10.1542/pir.19-9-291.
• Jiang H, Wong WH. Statistical inferences for isoform expression in RNA-Seq. Bioinformatics. 2009 Apr 15;25(8):1026-32. doi: 10.1093/bioinformatics/btp113. Epub 2009 Feb 25.
• Li J, Jiang H, Wong WH. Modeling non-uniformity in short-read rates in RNA-Seq data. Genome Biol. 2010;11(5):R50. doi: 10.1186/gb-2010-11-5-r50. Epub 2010 May 11.
• Anders S, Huber W. Differential expression analysis for sequence count data. Genome Biol. 2010;11(10):R106. doi: 10.1186/gb-2010-11-10-r106. Epub 2010 Oct 27.

Helpful Links

• University of Wisconsin-Madison Department of Pediatrics Research Information

Study record dates

Study Major Dates

• Study Start (Actual): May 9, 2011
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): June 1, 2028

Study Registration Dates

• First Submitted: March 8, 2012
• First Submitted That Met QC Criteria: March 16, 2012
• First Posted (Estimated): March 20, 2012

Study Record Updates

• Last Update Posted (Actual): February 18, 2026
• Last Update Submitted That Met QC Criteria: February 13, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Streptococcus; Streptococcus pyogenes
• Additional Relevant MeSH Terms: Stomatognathic Diseases; Respiratory Tract Infections; Infections; Respiratory Tract Diseases; Otorhinolaryngologic Diseases; Pharyngeal Diseases; Pharyngitis
• Other Study ID Numbers: 2015-1456 (Institutional Review Board - 5 year replacement); 2011-0058 (Other Identifier: IRB number - replaced); A536700 (Other Identifier: UW Madison); SMPH\PEDIATRICS\PEDIATRICS (Other Identifier: UW Madison); 1R21AI147502-01 (U.S. NIH Grant/Contract); Protocol Version 9/14/2023 (Other Identifier: UW Madison)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No