Scarlet fever

Scarlet fever is a bacterial infection linked to Streptococcus pyogenes, also called group A Streptococcus (GAS) ^[1]. The source material describes GAS as highly adapted to the human host and capable of causing asymptomatic infection, pharyngitis, pyoderma, scarlet fever, and invasive disease, with possible post-infection immune sequelae ^[1]. The provided evidence does not supply a more granular etiologic description of scarlet fever beyond this GAS association ^[1].

The source snippets do not provide a dedicated symptom profile for scarlet fever itself, so source-backed detail on rash pattern, timing, fever course, or classic complications is not yet available. What is supported is that GAS can manifest as pharyngitis, pyoderma, scarlet fever, or invasive disease, and may trigger post-infection immune sequelae ^[1]. In related GAS pharyngitis literature, fever, tonsillar exudate, and cervical lymphadenitis increase clinical suspicion, while cough suggests a viral cause ^[2]. However, these findings are for streptococcal pharyngitis rather than scarlet fever specifically and should be read as contextual, not diagnostic, evidence ^[2].

The supplied materials do not characterize scarlet fever’s geographic distribution, seasonality, outbreak context, or current surveillance burden directly, so those details are not yet available from the evidence boundary. At the organism level, GAS epidemiology is described as fluctuating globally, with the emergence of new clones often linked to acquisition of new virulence or antimicrobial determinants ^[1]. In the United States, GAS pharyngitis is described as a common infection responsible for more than 6 million office visits annually, but only 10% of adults seeking care for sore throat have GAS pharyngitis ^[2]. This utilization statistic pertains to GAS pharyngitis rather than scarlet fever specifically ^[2].

The provided sources do not state a scarlet-fever-specific transmission route. For GAS more generally, the organism is described as deploying virulence determinants that support colonization, dissemination within the host, and transmission, but the snippet does not specify the exposure mechanism ^[1]. Source-backed detail on droplet, contact, or environmental persistence is therefore not yet available from the supplied material ^[1].

The sources do not provide a scarlet-fever-specific risk group profile. For GAS pharyngitis, clinical suspicion is increased by ages 3 to 15 years, fever, tonsillar exudate, and cervical lymphadenitis, while cough points more toward a viral etiology ^[2]. These age and symptom associations apply to streptococcal pharyngitis evaluation and should not be overextended to scarlet fever without further evidence ^[2].

No scarlet-fever-specific preventive package is described in the provided sources. For GAS pharyngitis, guidelines recommend clinical decision rules followed by rapid antigen testing when the diagnosis is unclear before antibiotics are prescribed, and throat culture is recommended in children and adolescents after a negative rapid antigen test ^[2]. The sources also note that tonsillectomy is rarely recommended as a preventive measure for recurrent streptococcal pharyngitis ^[2]. These recommendations are relevant to GAS pharyngitis management and stewardship, but the snippets do not establish them as scarlet fever-specific prevention ^[2].

In surveillance contexts, scarlet fever should be interpreted as part of the broader GAS disease spectrum described in the sources, rather than as a separately quantified entity ^[1]. The available material emphasizes that GAS epidemiology is dynamic and that new clones with altered virulence or antimicrobial determinants can emerge, which may affect observed patterns over time ^[1]. Because the supplied snippets do not provide scarlet-fever-specific case definitions, reporting thresholds, or trend data, source-backed detail on local monitoring criteria is not yet available ^[1].

1. 1 Brouwer S et al. Pathogenesis, epidemiology and control of Group A Streptococcus infection. Nat Rev Microbiol. 2023 Jul. PMID: 36894668. doi: 10.1038/s41579-023-00865-7. PubMed: https://pubmed.ncbi.nlm.nih.gov/36894668/
2. 2 Hamilton JL et al. Streptococcal Pharyngitis: Rapid Evidence Review. Am Fam Physician. 2024 Apr. PMID: 38648833. PubMed: https://pubmed.ncbi.nlm.nih.gov/38648833/
3. 3 Griffiths CEM et al. Psoriasis. Lancet. 2021 Apr 3. PMID: 33812489. doi: 10.1016/S0140-6736(20)32549-6. PubMed: https://pubmed.ncbi.nlm.nih.gov/33812489/
4. 4 THE ASSOCIATE INFECTIONS OF SCARLET FEVERS. JAMA: The Journal of the American Medical Association. 1899. doi: 10.1001/jama.1899.92450770010002d. DOI: https://doi.org/10.1001/jama.1899.92450770010002d
5. 5 Scarlet Fever. The Boston Medical and Surgical Journal. 1877. doi: 10.1056/nejm187701180960307. DOI: https://doi.org/10.1056/nejm187701180960307
6. 6 SCARLET FEVER. The Lancet. 1884. doi: 10.1016/s0140-6736(02)22600-8. DOI: https://doi.org/10.1016/s0140-6736(02)22600-8

ICD-10

A38

ICD-11

1C1Z

Total cases

990K

Total deaths

9

Peak month

2017-01

Coverage

3 reporting countries · 2010-01-01 → 2026-06-01