Group A Strep Disease Surveillance and Trends

Key points

  • CDC tracks invasive group A Streptococcus (group A strep) disease using 2 surveillance systems.
  • Invasive disease refers to when bacteria invade parts of the body, like blood, that are normally free from germs.
An illustration of generic data

Data systems

National Notifiable Diseases Surveillance System

Streptococcal toxic shock syndrome (STSS) is the only nationally notifiable disease caused by group A strep bacteria.

CDC collects national information about STSS through the National Notifiable Diseases Surveillance System (NNDSS). CDC receives NNDSS data each week.

Keep Reading: National Notifiable Diseases Surveillance System (NNDSS)

Active Bacterial Core surveillance

CDC collaborates with some state health departments and academic institutions to conduct group A strep surveillance for invasive disease including:

  • Cellulitis with bacteremia (bloodstream infection)
  • Necrotizing fasciitis
  • Pneumonia with bacteremia
  • STSS

Information is collected through Active Bacterial Core surveillance (ABCs), which is part of CDC's Emerging Infections Program.

Keep Reading: Active Bacterial Core surveillance (ABCs)

Bact Facts Interactive‎‎

You can analyze and visualize ABCs invasive group A strep disease data.
Use Bact Facts Interactive

How the data are interpreted

View Larger
A chart showing rates of invasive group A Streptococcus infections overall and for adults 65 years and older from 1996 through 2022 using Active Bacterial Core surveillance data.
Adults 65 years and older have the highest rates of invasive disease. Source: ABCs

Invasive disease burden

Looking at U.S. invasive group A strep disease data for the last five years, CDC estimates there were between

  • 20,000 to 27,000 cases each year
  • 1,800 and 2,400 deaths each year

Invasive disease trends

Adults

The U.S. rates of invasive group A strep disease began increasing in 2014.

The increase was largest among adults aged 18 through 64 years old, but the rate also increased among older adults. Substantial increases in cases among two groups appear to account for much of the change:

  • People experiencing homelessness
  • People with injection drug use

Children

Rates among children have been stable, except for a decrease seen during the COVID-19 pandemic. During that time, measures to reduce the spread of respiratory disease were implemented.

Antibiotic resistance

Through ABCs, CDC tracks data on group A strep isolate resistance to certain antibiotics.

Generally, group A strep bacteria are not resistant to the first-line antibiotics for strep throat: penicillin and amoxicillin.

Antibiotic resistance limits treatment options‎

Around 1 in 3 invasive group A strep infections are now caused by bacteria that are resistant to erythromycin and clindamycin.
Use Bact Facts Interactive to see how this trend is changing

Estimating non-invasive infections

In the United States

Experts estimate that several million cases of non-invasive group A strep infections occur in the United States each year. Non-invasive group A strep infections include:

For example, strep throat causes an estimated 5.2 million outpatient visits each year among people younger than 65 years old1. These visits result in 2.8 million antibiotic prescriptions each year.

Globally

Globally, the burden from non-invasive group A strep infections is even greater. For example, the World Health Organization estimates that each year2

  • Over 100 million children worldwide have impetigo
  • Over 600 million have pharyngitis due to group A strep

Trends in seasonality

Group A strep infections can occur any time during the year. However, some infections are more common in the United States in certain seasons:

  • Strep throat and scarlet fever: Winter and spring
  • Impetigo and other skin infections: Summer

Estimating complications

Complications from group A strep infections include:

In the United States

Acute rheumatic fever incidence is significantly less common in the United States and developed countries compared to less developed countries. However, there's likely significant regional variation as seen in the annual incidence rates shown below:

  • American Samoa and Hawaii: 1.1 to 1.5 cases per 1,000 population34
  • Tennessee: 0.6 cases per 100,000 population5
  • Utah: 3.7 cases per 100,000 population6

Asian and Pacific Islander people are more likely to be hospitalized for acute rheumatic fever compared to White people7:

Globally

Worldwide, rheumatic heart disease remains a significant cause of cardiovascular disease and death. The World Health Organization estimates2:

  • 470,000 new cases of acute rheumatic fever occur each year
  • 282,000 new cases of rheumatic heart disease occur each year

In 2015, there was an estimated 33.4 million cases of rheumatic heart disease8.

In addition, over 300,000 people die each year from rheumatic heart disease or its complications9.

An estimated 470,000 cases of PSGN occur each year globally2.

Data reporting

View NNDSS infectious disease data tables.

View ABCs annual reports for group A strep disease.

Data definitions

The Council of State and Territorial Epidemiologists (CSTE) released the most recent case definition for STSS in 2010.

Resources

Report: Antibiotic resistance threats in the United States, 2019
CDC

The current evidence for the burden of group A streptococcal diseases (2005)
World Health Organization

A review of the technical basis for the control of conditions associated with GAS infections (2005)
World Health Organization

Standardized case definitions and best practice surveillance protocols for clinical manifestations of group A Streptococcus infections
Strep A Vaccine Global Consortium

Print
Content Source:
National Center for Immunization and Respiratory Diseases; Division of Bacterial Diseases
  1. Lewnard JA, King LM, Fleming-Dutra KE, Link-Gelles R, Van Beneden CA. Incidence of pharyngitis, sinusitis, acute otitis media, and outpatient antibiotic prescribing preventable by vaccination against group A Streptococcus in the United States. Clin Infect Dis. 2021;73(1):e47–e58.
  2. Carapetis JR, Steer AC, Mulholland EK, Weber M. The global burden of group A streptococcal diseases. Lancet Infect Dis. 2005;5(11):685–94.
  3. Erdem G, Mizumoto C, Esaki D, et al. Group A streptococcal isolates temporally associated with acute rheumatic fever in Hawaii: Differences from the continental United States. Clin Infect Dis. 2007;45:e20–4.
  4. Beaudoin A, Edison L, Introcaso CE, Goh L, Marrone J, Mejia A, Van Beneden C. Acute rheumatic fever and rheumatic heart disease among children—American Samoa, 2011–2012. MMWR Morb Mortal Wkly Rep. 2015; 64(20);555–8.
  5. Land MA, Bisno AL. Acute rheumatic fever: A vanishing disease in suburbia. JAMA. 1983;249(7):895–98.
  6. Stockmann C, Ampofo K, Hersh AL, et al. Evolving epidemiologic characteristics of invasive group A streptococcal disease in Utah, 2002–2010. Clin Infect Dis. 2012;55(4):479–87.
  7. Bradley-Hewitt T, Longenecker CT, Nkomo V, et al. Trends and presentation patterns of acute rheumatic fever hospitalisations in the United States. Cardiol Young. 2019;29(11):1387–90.
  8. Watkins DA, Johnson CO, Colquhoun SM, et al. Global, regional, and national burden of rheumatic heart disease, 1990-2015. N Engl J Med. 2017;377(8):713-722.
  9. Global Burden of Disease Collaborative Network. Global Burden of Disease Study 2016 (GBD 2016) Results. Seattle, United States: Institute for Health Metrics and Evaluation (IHME), 2017, available at https://vizhub.healthdata.org/gbd-results/ (accessed 20 March 2018).