Group A streptococcal infections: report on seasonal activity in England, 2022 to 2023 | Daily News Byte

Group A streptococcal infections: report on seasonal activity in England, 2022 to 2023

 | Daily News Byte


Scarlet fever notifications and GP consultations in England are higher than normal for this point in the season, after being higher than expected later in the season.

Notices of invasive group A streptococcus (iGAS) disease follows a similar trend and is slightly higher than expected for this time of year. A relatively high rate of iGAS reported in children and may reflect an increase in respiratory viruses.

Given the potential for severe presentation in children, it remains important that scarlet fever cases are treated promptly with antibiotics to limit further spread and reduce the risk of possible complications in cases and their close contacts. Because of these uncommon but potentially serious complications, physicians and health care teams (HPTs) should continue to bear in mind the potential increase in invasive disease and maintain a high degree of clinical suspicion when evaluating patients, particularly those with previous viral infections (including chickenpox) or close contacts of scarlet fever.

According to national guidance, immediate notification of scarlet fever cases and outbreaks to local UK health security agencies (UKHSA) HPTsObtaining a throat swab (before starting antibiotics) when there is uncertainty about the diagnosis, and excluding the case from school or work until 24 hours of antibiotic treatment has been received, remain essential tools to limit spread.

Scarlet fever

Following the expected summer scarlet fever activity in England, notifications are increasing and continuing through the early part of the current season (2022 to 2023; seasons are defined from mid-September to mid-September), with a reduction during August. above what is normally seen at this time of year (Figure 1).

A total of 4,622 notifications of scarlet fever were received in England this season (2022 to 2023) from weeks 37 to 46, with 851 notifications received in week 46. This compares with an average of 1,294 (range 258 to 2,008) for the same period. (Weeks 37 to 46) in the previous 5 years.

Figure 1. Weekly scarlet fever notifications in England, by season, 2017 to 2018

There has been considerable variation across England in scarlet fever notifications to date this season, ranging between 3.9 (London) and 13.0 (North West) per 100,000 population (Table 1).

Table 1. Number and rate per 100,000 population of scarlet fever and iGAS Instructions in England: Weeks 37 to 46 of the 2022 to 2023 season

territory Number of cases of scarlet fever Rate of scarlet fever Number of cases of iGAS Rate of iGAS
East of England 436 6.5 39 0.6
East Midlands 578 11.9 40 0.8
London 347 3.9 71 0.8
North East 234 8.7 26 1.0
North West 957 13.0 74 1.0
South East 638 7.1 85 1.0
South West 404 7.3 49 0.9
West Midlands 418 7.0 51 0.9
Yorkshire and the Humber 610 11.0 75 1.4
England has been kept at 4,622 8.2 510 0.9

Aggressive group A streptococcal infection

Like scarlet fever, during the latter half of the last season (2021 to 2022), the level of iGAS Notifications in England were higher than expected (Figure 1). Laboratory Instructions of iGAS So far this season (Weeks 37 to 46, 2022 to 2023) has exceeded expectations. There have been 509 notifications so far this season iGAS The disease was reported through laboratory surveillance in England, with a weekly high of 73 notifications in week 46.

Laboratory Instructions of iGAS are more than those recorded in the last 5 seasons (average 248, range 142 to 357 notifications; Figure 2).

Figure 2.’s weekly laboratory instructions iGASEngland, by season, 2017 to 2018 onwards

During the current season so far, the highest rates by far have been recorded in the Yorkshire and Humber region (1.4 per 100,000 population), followed by the North East, South East and North West regions (each 1.0 per 100,000; Table 1). The highest rate was among those 75 years and older (2.4 per 100,000), followed by the 1 to 4 year age group (2.3 per 100,000) and those 1 year and younger (1.3 per 100,000).

rate of iGAS All age groups are higher at this stage of the season compared to the pre-epidemic average (Table 2).

Table 2. Rate per 100,000 population iGAS Instructions by age group in England, weeks 37 to 46

Note: In this table, ‘pre-pandemic period’ is the average rate per 100,000 population recorded in the 3 pre-pandemic seasons: 2017 to 2018, 2018 to 2019 and 2019 to 2020. ‘Pandemic’ rate is the average rate from 2020 to 2021 and 2021 Enrolled in the 2022 season.

Age Group (Years) Pre-pandemic (2017/18 to 2019/20) Pandemic (2020/21 to 2021/22) 2022 to 2023
Under 1 1.1 0.2 1.3
1 to 4 0.5 0.2 2.3
5 to 9 0.3 0.1 1.1
10 to 14 0.1 0.3 0.2
15 to 44 0.4 0.2 0.5
45 to 64 0.5 0.2 0.6
65 to 74 0.7 0.3 1.3
75 and above 1.9 1.0 2.4

Mean age of patients with iGAS The prevalence was 50 years (range 1 year and under, to 102 years), slightly lower than the range seen at this point in the previous 5 seasons (ages 54 to 57 years); 21% iGAS Infections reported so far this season are among children (age 10 and under), which is higher than the range of the previous 5 seasons (5% to 11%).

So far this season, 5 deaths have been reported in 7 days iGAS Diagnosis of infection (from any cause) in children under 10 years of age. This compares to 4 deaths over the same period in the 2017 to 2018 (pre-pandemic) season, our last high season. GAS infection

Antimicrobial susceptibility results from routine laboratory surveillance so far this season show tetracycline resistance in 25%. GAS sterile site isolates; This is lower than last season (45%) at this point. Sensitivity test of iGAS Isolates against erythromycin showed that 7% were resistant (compared to 19% last season), and for clindamycin, 7% were resistant at this point in the season (16% last season). Isolates remained universally susceptible to penicillin.

Reference laboratory analysis iGAS Isolate submissions indicate a diverse range of emm gene sequence types identified between October and November 2022. The results show that emm 1 is the most common (24% of referrals), followed by emm 12 (20%), emm 89 (8%) , emm 108 and emm 33 (5% each). In 2022, emm 12 and emm 1 dominate among children (15 years and below), at 39% and 35%, respectively. In contrast, during 2021, emm 89 was the most frequently identified (13%), followed by emm 108 (12%), then emm 66 (11%).


The start of the 2022 to 2023 season has seen a sharp increase in scarlet fever notifications and GP consultations that are higher than expected at this time of year. rate of iGAS Infection notifications are following a similar but less pronounced increase, with weekly incidence trending slightly higher than would be expected at this point in the season.

Among children under 10 years of age, the rate iGAS Infections are higher than levels reported in previous years COVID-19 Epidemic but significantly higher than last 2 years. An investigation is underway following reports of increased lower respiratory tract infections GAS Infections, especially empyema, in children in the last few weeks.

The elevated iGAS Levels in children compared to the period when these epidemic control measures were in effect may be the result of increased scarlet fever activity given the crossover of strains involved in both presentations (1, 2).

Prompt treatment of scarlet fever with antibiotics is recommended to reduce the risk of possible complications and limit further transmission. Public health communications are ongoing to encourage contact with NHS 111 and/or GP practices for clinical assessment of patients with specific symptoms (for example, rash). GPs and other frontline clinical staff are reminded of the increased risk of invasive disease in household contacts of scarlet fever cases (3, 4).

Clinicians should continue to be aware of the potential increase in invasive disease and maintain a high index of suspicion in concerned patients and provide safety maintenance advice as appropriate, such as early identification and prompt initiation of specific and supportive therapy for patients. iGAS Infections can save lives.

Relevant guidance and information can be found on GOV.UK:

Suspected clusters or outbreaks of invasive disease isolates and non-invasive isolates should be submitted to:

Staphylococcus and Streptococcus Reference Section

Antimicrobial Resistance and Healthcare Associated Infections (AMRHAI)

UK Health Protection Agency

61 Colindale Avenue




1. Chalker V, Jironkin A, Coelho J, El-Shahib A, Platt S, Kapatai G, et al (2017). ‘Genome analysis following the national increase in scarlet fever in England 2014’. BMC Genomics: Volume 18 Number 1, Page 224

2. Al-Shahib A, Underwood A, Afshar B, Turner CE, Lamagni T, Sriskandan S, et al (2106). Emergence of a novel lineage containing prophages in emm/M3 group A streptococcus associated with an outbreak of invasive disease in the UK. mGen; Volume 2 Number 11

3. Lamagni T, and others (2018). ‘The resurgence of scarlet fever in England, 2014–16: a population-based surveillance study’. The Lancet Infectious Diseases: Volume 18, Number 2, Pages 180 to 187

4. Watts V, et al (2019). ‘Increased risk of invasive group A streptococcus disease for household contacts of scarlet fever cases, England, 2011–2016’. Emerging Infectious Diseases: Volume 25, Number 3, Pages 529 to 537


These reports would not be possible without the weekly contributions of microbiology colleagues in laboratories across England, without whom there would be no surveillance data.

Will get support from internal colleagues UKHSAAnd AMRHAI A reference unit, in particular, is valuable in report preparation.

Feedback and specific questions about this report are welcome via


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