Historical aspects of rheumatic fever

Evaluating the implementation of a dynamic digital application to enable community-based decentralisation of rheumatic heart disease case management in Uganda: protocol for a hybrid type III effectiveness-implementation study

INTRODUCTION

Rheumatic heart disease (RHD) affects over 39 million people worldwide, the majority in low-income and middle-income countries. Secondary antibiotic prophylaxis (SAP), given every 3-4 weeks can improve outcomes, provided more than 80% of doses are received. Poor adherence is strongly correlated with the distance travelled to receive prophylaxis. Decentralising RHD care has the potential to bridge these gaps and at least maintain or potentially increase RHD prophylaxis uptake. A package of implementation strategies was developed with the aim of reducing barriers to optimum SAP uptake.

METHODS AND ANALYSIS

A hybrid implementation-effectiveness study type III was designed to evaluate the effectiveness of a package of implementation strategies including a digital, cloud-based application to support decentralised RHD care, integrated into the public healthcare system in Uganda. Our overarching hypothesis is that secondary prophylaxis adherence can be maintained or improved via a decentralisation strategy, compared with the centralised delivery strategy, by increasing retention in care. To evaluate this, eligible patients with RHD irrespective of their age enrolled at Lira and Gulu hospital registry sites will be consented for decentralised care at their nearest participating health centre. We estimated a sample size of 150-200 registrants. The primary outcome will be adherence to secondary prophylaxis while detailed implementation measures will be collected to understand barriers and facilitators to decentralisation, digital application tool adoption and ultimately its use and scale-up in the public healthcare system.

ETHICS AND DISSEMINATION

This study was approved by the Institutional Review Board (IRB) at Cincinnati Children's Hospital Medical Center (IRB 2021-0160) and Makerere University School of Medicine Research Ethics Committee (Mak-SOMREC-2021-61). Participation will be voluntary and informed consent or assent (>8 but <18) will be obtained prior to participation. At completion, study findings will be communicated to the public, key stakeholders and submitted for publication.

Research priorities for the primordial prevention of acute rheumatic fever and rheumatic heart disease by modifying the social determinants of health

The social determinants of health (SDH), such as access to income, education, housing and healthcare, strongly shape the occurrence of acute rheumatic fever (ARF) and rheumatic heart disease (RHD) at the household, community and national levels. The SDH are systemic factors that privilege some more than others and result in poverty and inequitable access to resources to support health and well-being. Primordial prevention is the modification of SDH to improve health and reduce the risk of disease acquisition and the subsequent progression to RHD. Modifying these determinants using primordial prevention strategies can reduce the risk of exposure to Group A Streptococcus, a causative agent of throat and skin infections, thereby lowering the risk of initiating ARF and its subsequent progression to RHD.This report summarises the findings of the Primordial Prevention Working Group-SDH, which was convened in November 2021 by the National Heart, Lung, and Blood Institute to assess how SDH influence the risk of developing RHD. Working group members identified a series of knowledge gaps and proposed research priorities, while recognising that community engagement and partnerships with those with lived experience will be integral to the success of these activities. Specifically, members emphasised the need for: (1) global analysis of disease incidence, prevalence and SDH characteristics concurrently to inform policy and interventions, (2) global assessment of legacy primordial prevention programmes to help inform the co-design of interventions alongside affected communities, (3) research to develop, implement and evaluate scalable primordial prevention interventions in diverse settings and (4) research to improve access to and equity of services across the RHD continuum. Addressing SDH, through the implementation of primordial prevention strategies, could have broader implications, not only improving RHD-related health outcomes but also impacting other neglected diseases in low-resource settings.

Risk factors for acute rheumatic fever: A case-control study

BACKGROUND

Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) remain an inequitable cause of avoidable suffering and early death in many countries, including among Indigenous Māori and Pacific populations in New Zealand. There is a lack of robust evidence on interventions to prevent ARF. This study aimed to identify modifiable risk factors, with the goal of producing evidence to support policies and programs to decrease rates of ARF.

METHODS

A case-control study was undertaken in New Zealand using hospitalised, first episode ARF cases meeting a standard case-definition. Population controls (ratio of 3:1) were matched by age, ethnicity, socioeconomic deprivation, location, sex, and recruitment month. A comprehensive, pre-tested questionnaire was administered face-to-face by trained interviewers.

FINDINGS

The study included 124 cases and 372 controls. Multivariable analysis identified strong associations between ARF and household crowding (OR 3·88; 95%CI 1·68-8·98) and barriers to accessing primary health care (OR 2·07; 95% CI 1·08-4·00), as well as a high intake of sugar-sweetened beverages (OR 2·00; 1·13-3·54). There was a marked five-fold higher ARF risk for those with a family history of ARF (OR 4·97; 95% CI 2·53-9·77). ARF risk was elevated following self-reported skin infection (aOR 2·53; 1·44-4·42) and sore throat (aOR 2·33; 1·49-3·62).

INTERPRETATION

These globally relevant findings direct attention to the critical importance of household crowding and access to primary health care as strong modifiable causal factors in the development of ARF. They also support a greater focus on the role of managing skin infections in ARF prevention.

FUNDING

This research was funded by the Health Research Council of New Zealand (HRC) Rheumatic Fever Research Partnership (supported by the New Zealand Ministry of Health, Te Puni Kōkiri, Cure Kids, Heart Foundation, and HRC) award number 13/959.

Rheumatic Heart Disease in Pregnancy: New Strategies for an Old Disease?

RHD in pregnancy (RHD-P) is associated with an increased burden of maternal and perinatal morbidity and mortality. A sequellae of rheumatic fever resulting in heart valve damage if untreated, RHD is twice as common in women. In providing an historical overview, this commentary provides context for prevention and treatment in the 21 st century. Four underlying themes inform much of the literature on RHD-P: its association with inequities; often-complex care requirements; demands for integrated care models, and a life-course approach. While there have been some gains particularly in awareness, strengthened policies and funding strategies are required to sustain improvements in the RHD landscape and consequently improve outcomes. As the principal heart disease seen in pregnant women in endemic regions, it is unlikely that the Sustainable Development Goal 3 target of reduced global maternal mortality ratio can be met by 2030 if RHD is not better addressed for women and girls.

The clinical value of ficolin-3 gene polymorphism in rheumatic heart disease. An Egyptian adolescents study

OBJECTIVE

Ficolin-3 is one of the innate immunity molecules that was thought to play a pivotal role in Streptococcus pyogenes autoimmunity and its complications; rheumatic fever (RF) and rheumatic heart disease (RHD). We aimed to disclose if there is an association between ficolin-3 (FCN3) gene polymorphisms (rs4494157 and rs10794501) and RF with or without RHD for the first time in Egyptian adolescents.

RESULTS

Serum ficolin-3 level was significantly elevated in patients suffering from RF with and without RHD in comparison with control. Regarding FCN3 gene (rs4494157) polymorphism, a significant correlation was found between the A allele and the susceptibility to RF with or without RHD (OR = 2.93, P = 0.0002 and OR = 2.23, P = 0.008 respectively). Besides, AA homozygous genotype showed a significant association with RHD risk (OR = 3.47, P = 0.026). Patients carrying the A allele (CA + AA) had significantly higher serum ficolin-3 than those carrying the CC genotype (P ˂ 0.0001). While the frequency of (rs10794501) polymorphism revealed no significant differences between the controls and RF patients with or without RHD (OR = 1.43, P = 0.261 and OR = 1.48, P = 0.208 respectively).

The use of cardiac valve procedures for rheumatic heart disease in Australia; a cross-sectional study 2002-2017

Background

Australia, although a high income economy, carries a significant burden of rheumatic heart disease (RHD). Acute rheumatic fever (ARF) and RHD are endemic in the Indigenous population. Immigrants from low/lower-income countries (‘non-Indigenous high-risk’) are also at increased risk compared with ‘non-Indigenous low-risk’ Australians. This study describes the utilisation of surgical and percutaneous procedures for RHD-related valve disease among patients aged less than 50 years, from 2002 to 2017.

Methods

A descriptive study using data from the ‘End RHD in Australia: Study of Epidemiology (ERASE) Project’ linking RHD Registers and hospital inpatient data from five states/territories, and two surgical databases. Trends across three-year periods were determined and post-procedural all-cause 30-day mortality calculated.

Results

A total of 3900 valves interventions were undertaken in 3028 procedural episodes among 2487 patients. Over 50% of patients were in the 35–49 years group, and 64% were female. Over 60% of procedures for 3-24 year-olds were for Indigenous patients. There were few significant changes across the study period other than downward trends in the number and proportion of procedures for young Indigenous patients (3–24 years) and ‘non-Indigenous/low risk’ patients aged ≥35 years. Mitral valve procedures predominated, and multi-valve interventions increased, including on the tricuspid valve. The majority of replacement prostheses were mechanical, although bioprosthetic valve use increased overall, being highest among females <35 years and Indigenous Australians. All-cause mortality (n = 42) at 30-days was 1.4% overall (range 1.1–1.7), but 2.0% for Indigenous patients.

Conclusions

The frequency of cardiac valve procedures, and 30-day mortality remained steady across 15 years. Some changes in the distribution of procedures in population groups were evident. Replacement procedures, the use of bioprosthetic valves, and multiple-valve interventions increased. The challenge for Australian public health officials is to reduce the incidence, and improve the early detection and management of ARF/RHD in high-risk populations within Australia.

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Epidemic RHD in Indigenous Australians drives RHD-related cardiac valve procedures.

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30-day mortality post-procedural is low in those under 50 years.

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Bioprosthetic valve replacements higher in young women, and increasing in older patients.

Ficolin-3 in rheumatic fever and rheumatic heart disease

Rheumatic fever (RF) and chronic rheumatic heart disease (RHD) are complications of oropharyngeal infection caused by Streptococcus pyogenes. Despite the importance of the complement system against infections and autoimmunity diseases, studies on the role of the lectin pathway in RF and RHD are scarce. Thus, our aim was to evaluate the association of ficolin-3 serum levels, FCN3 polymorphisms and haplotypes with the susceptibility to RF and RHD. We investigated 179 patients with a history of RF (126 RHD and 53 RF only) and 170 healthy blood donors as control group. Ficolin-3 serum concentrations were measured using enzyme-linked immunosorbent assay (ELISA). Three FCN3 single nucleotide polymorphisms (SNPs rs532781899, rs28362807 and rs4494157) were genotyped through the sequence-specific PCR method. Lower ficolin-3 serum levels were observed in RF patients when compared to controls (12.81 μg/mL vs. 18.14 μg/mL respectively, p < 0.0001, OR 1.22 [1.12-1.34]), and in RHD in comparison to RF only (RFo) (12.72 μg/mL vs. 14.29 μg/mL respectively, p = 0.016, OR 1.38 [1.06-1.80]). Low ficolin-3 levels (<10.7 μg/mL) were more common in patients (39.5 %, 30/76) than controls (20.6 %, 13/63, p = 0.018, OR = 2.51 [1.14-5.31]), and in RHD (44.4 %, 28/63) than RFo (15.4 %, 2/13, p = 0.007, OR = 3.08 [1.43-6.79]). On the other hand, FCN3 polymorphism/haplotypes were not associated with ficolin-3 serum levels or the disease. Low ficolin-3 levels might be associated with RF, being a potential marker of disease progression.

Streptococcal Infection as a Major Historical Cause of Stuttering: Data, Mechanisms, and Current Importance

Stuttering is one of the most well-known speech disorders, but the underlying neurological mechanisms are debated. In addition to genetic factors, there are also major non-genetic contributions. It is here proposed that infection with group A beta-hemolytic streptococcus (GAS) was a major underlying cause of stuttering until the mid-1900s when penicillin was introduced in 1943. The main mechanism proposed is an autoimmune reaction from tonsillitis, targeting specific molecules, for example within the basal ganglia. It is here also proposed that GAS infections may have continued to cause stuttering to some extent, to the present date, though more rarely. If so, early diagnosis of such cases would be of importance. Childhood cases with sudden onset of stuttering after throat infection may be particularly important to assess for possible GAS infection. The support for this hypothesis primarily comes from three lines of argument. First, medical record data from the 1930s strongly indicates that there was one type of medical event in particular that preceded the onset of childhood stuttering with unexpected frequency: diseases related to GAS throat infections. In particular, this included tonsillitis and scarlet fever, but also rheumatic fever. Rheumatic fever is a childhood autoimmune sequela of GAS infection, which was a relatively widespread medical problem until the early 1960s. Second, available reports of changes of the childhood prevalence of stuttering indicate striking parallels between stuttering and the incidence of rheumatic fever, with: (1) decline from the early 1900s; (2) marked decline from the introduction of penicillin in the mid 1940s; and (3) reaching a more stable level in the 1960s. The correlations between the data for stuttering and rheumatic fever after the introduction of penicillin are very high, at about 0.95. Third, there are established biological mechanisms linking GAS tonsillitis to immunological effects on the brain. Also, a small number of more recent case reports have provided further support for the hypothesis linking stuttering to GAS infection. Overall, it is proposed that the available data provides strong evidence for the hypothesis that GAS infection was a major cause of stuttering until the mid-1900s, interacting with genetic predisposition.

Incidence of acute rheumatic fever and rheumatic heart disease in Melbourne, Australia from 1937 to 2013

AIM

Acute rheumatic fever (ARF) most commonly presents in children aged 5-14 years old. Lifelong rheumatic heart disease (RHD) can result. This study investigated time trends in ARF and RHD using inpatient data from the Royal Children's Hospital, Melbourne (RCH).

METHODS

A retrospective cohort study covering the period 1937-2013 was conducted using records from RCH, a quaternary paediatric hospital in Melbourne, Victoria, Australia. Patient data were identified using RCH classification of diseases coding for ARF or RHD for years <1952. For the period 1952-1987, this system was used in addition to identifying International Classification of Disease (ICD) discharge codes that corresponded to ARF or RHD. From 1988-2013, only ICD codes were used to identify patient data. Descriptive epidemiological analyses were performed, including incidence rate calculations using historical census population denominator data. Analyses focussed on children in the peak age group.

RESULTS

Among children aged five to 14 years, a total of 4337 RCH admissions with ARF/RHD occurred for 3015 patients. A sharp decline in first ARF/RHD hospitalisations at RCH occurred from 1959, following a peak mean annual incidence rate during 1944-1947 of 40.1/100 000 children (95% confidence interval (CI): 36.6-43.9; P < 0.05). Over 1996-2013, the mean annual incidence rate was 1.6/100 000 (95% CI: 1.3-1.8) and reached 2.3/100 000 (95% CI: 1.3-3.7) in 2005.

CONCLUSION

The burden of ARF and RHD treated at RCH declined following the 1940s, mirroring changes seen in North America and Europe. Despite this, inpatient treatment for these conditions continued to be provided right up until the end of the study period.

Genetic Basis of Myocarditis: Myth or Reality?

The genetic basis of myocarditis remains an intriguing concept, at least as long as the definition of myocarditis constitutes the definitive presence of myocardial inflammation sufficient to cause the observed ventricular dysfunction in the setting of cardiotropic infections. Autoimmune or immune-mediated myocardial inflammation constitutes a complex area of clinical interest, wherein numerous and not yet fully understood role of hereditary auto-inflammatory diseases can result in inflammation of the pericardium and myocardium. Finally, myocardial involvement in hereditary immunodeficiency diseases, cellular and humoral, is a possible trigger for infections which may complicate the diseases themselves. Whether the role of constitutional genetics can make the patient susceptible to myocardial inflammation remains yet to be explored.

Risk Factors for Acute Rheumatic Fever: Literature Review and Protocol for a Case-Control Study in New Zealand

Acute rheumatic fever (ARF) and its sequela, rheumatic heart disease (RHD), have largely disappeared from high-income countries. However, in New Zealand (NZ), rates remain unacceptably high in indigenous Māori and Pacific populations. The goal of this study is to identify potentially modifiable risk factors for ARF to support effective disease prevention policies and programmes. A case-control design is used. Cases are those meeting the standard NZ case-definition for ARF, recruited within four weeks of hospitalisation for a first episode of ARF, aged less than 20 years, and residing in the North Island of NZ. This study aims to recruit at least 120 cases and 360 controls matched by age, ethnicity, gender, deprivation, district, and time period. For data collection, a comprehensive pre-tested questionnaire focussed on exposures during the four weeks prior to illness or interview will be used. Linked data include previous hospitalisations, dental records, and school characteristics. Specimen collection includes a throat swab (Group A Streptococcus), a nasal swab (Staphylococcus aureus), blood (vitamin D, ferritin, DNA for genetic testing, immune-profiling), and head hair (nicotine). A major strength of this study is its comprehensive focus covering organism, host and environmental factors. Having closely matched controls enables the examination of a wide range of specific environmental risk factors.

Primary prevention of rheumatic fever in the 21st century: evaluation of a national programme

Background

Acute rheumatic fever (ARF) has largely disappeared from high-income countries. However, in New Zealand (NZ) rates remain high in indigenous (Māori) and Pacific populations. In 2011, NZ launched an intensive and unparalleled primary Rheumatic Fever Prevention Programme (RFPP). We evaluated the impact of the school-based sore throat service component of the RFPP.

Methods

The evaluation used national trends of all-age first episode ARF hospitalisation rates before (2009-11) and after (2012-16) implementation of the RFPP. A retrospective cohort study compared first-episode ARF incidence during time-not-exposed (23 093 207 person-days) and time-exposed (68 465 350 person-days) with a school-based sore throat service among children aged 5-12 years from 2012 to 2016.

Results

Following implementation of the RFPP, the national ARF incidence rate declined by 28% from 4.0 per 100 000 [95% confidence interval (CI) 3.5-4.6] at baseline (2009-11) to 2.9 per 100 000 by 2016 (95% CI 2.4-3.4, P <0.01). The school-based sore throat service effectiveness overall was 23% [95% CI -6%-44%; rate ratio (RR) 0.77, 95% CI 0.56-1.06]. Effectiveness was greater in one high-risk region with high coverage (46%, 95% CI 16%-66%; RR 0.54, 95% CI 0.34-0.84).

Conclusions

Population-based primary prevention of ARF through sore throat management may be effective in well-resourced settings like NZ where high-risk populations are geographically concentrated. Where high-risk populations are dispersed, a school-based primary prevention approach appears ineffective and is expensive.

Sickening or Healing the Heart? The Association of Ficolin-1 and Rheumatic Fever

Rheumatic fever (RF) and its subsequent progression to rheumatic heart disease (RHD) are chronic inflammatory disorders prevalent in children and adolescents in underdeveloped countries, and a contributing factor for high morbidity and mortality rates worldwide. Their primary cause is oropharynx infection by Streptococcus pyogenes, whose acetylated residues are recognized by ficolin-1. This is the only membrane-bound, as well as soluble activator molecule of the complement lectin pathway (LP). Although LP genetic polymorphisms are associated with RF, FCN1 gene's role remains unknown. To understand this role, we haplotyped five FCN1 promoter polymorphisms by sequence-specific amplification in 193 patients (138 with RHD and 55, RF only) and 193 controls, measuring ficolin-1 serum concentrations in 78 patients and 86 controls, using enzyme-linked immunosorbent assay (ELISA). Patients presented lower ficolin-1 serum levels (p < 0.0001), but did not differ according to cardiac commitment. Control's genotype distribution was in the Hardy-Weinberg equilibrium. Four alleles (rs2989727: c.-1981A, rs10120023: c.-542A, rs10117466: c.-144A, and rs10858293: c.33T), all associated with increased FCN1 gene expression in whole blood or adipose subcutaneous tissue (p = 0.000001), were also associated with increased protection against the disease. They occur within the *3C2 haplotype, associated with an increased protection against RF (OR = 0.41, p < 0.0001) and with higher ficolin-1 levels in patient serum (p = 0.03). In addition, major alleles of these same polymorphisms comprehend the most primitive *1 haplotype, associated with increased susceptibility to RF (OR = 1.76, p < 0.0001). Nevertheless, instead of having a clear-cut protective role, the minor c.-1981A and c.-144A alleles were also associated with additive susceptibility to valvar stenosis and mitral insufficiency (OR = 3.75, p = 0.009 and OR = 3.37, p = 0.027, respectively). All associations were independent of age, sex or ethnicity. Thus, minor FCN1 promoter variants may play a protective role against RF, by encouraging bacteria elimination as well as increasing gene expression and protein levels. On the other hand, they may also predispose the patients to RHD symptoms, by probably contributing to chronic inflammation and tissue injury, thus emphasizing the dual importance of ficolin-1 in both conditions.

The fall and rise of Group A Streptococcus diseases

Streptococcus pyogenes (or Group A Streptococcus, GAS) is a Gram-positive human pathogen responsible for a diverse array of superficial, invasive and immune-related diseases. GAS infections have historically been diseases of poverty and overcrowding, and remain a significant problem in the developing world and in disadvantaged populations within developed countries. With improved living conditions and access to antibiotics, the rates of GAS diseases in developed societies have gradually declined during the 20th century. However, genetic changes in circulating GAS strains and/or changes in host susceptibility to infection can lead to dramatic increases in the rates of specific diseases. No situations exemplify this more than the global upsurge of invasive GAS disease that originated in the 1980s and the regional increases in scarlet fever in north-east Asia and the UK. In each case, increased disease rates have been associated with the emergence of new GAS strains with increased disease-causing capability. Global surveillance for new GAS strains with increased virulence is important and determining why certain populations suddenly become susceptible to circulating strains remains a research priority. Here, we overview the changing epidemiology of GAS infections and the genetic alterations that accompany the emergence of GAS strains with increased capacity to cause disease.

Epidemiology of an upsurge of invasive group A streptococcal infections in Ireland, 2012-2015

OBJECTIVES

Group A streptococcus (GAS) is responsible for mild to very severe disease. The epidemiology of an upsurge in invasive GAS (iGAS) infections in Ireland, 2012-2015 was investigated.

METHODS

Epidemiological typing of iGAS (n = 473) isolates was performed and compared to non-invasive (n = 517) isolates. Clinical data of notified iGAS was obtained from the national infectious disease information system.

RESULTS

Annual incidences of iGAS cases (n = 561) were 2.33-3.66 per 100,000 population. Bacteraemia was the most common clinical presentation (75%) followed by focus without bacteraemia (19%) and necrotizing faciitis (7%). Streptococcal toxic shock syndrome occurred in 19% of presentations. The main invasive emm types in rank order were emm1, emm3, emm28, emm12 and emm89 whereas emm4, emm28, emm3, emm12, emm89 and emm1 predominated in non-invasive infections. Invasive emm1 and emm3 showed annual fluctuations (15-48% and 4-37%, respectively) and predominated in most clinical presentations of iGAS. Superantigens speA, speG, speJ was associated with iGAS disease and, speC, speI and ssa with non-invasive infections. There was 4.3% erythromycin and 5.6% tetracycline resistance. The main resistant types were emm11, emm28 and emm77.

CONCLUSIONS

Cyclic increases in emm1 and emm3 occurred during the iGAS upsurge. Continued surveillance of GAS is therefore essential given the epidemiological changes that occur in a short time period.

Group A Streptococcus pharyngitis and pharyngeal carriage: A meta-analysis

Objective

Antibiotic treatment of Group A Streptococcus (GAS) pharyngitis is important in acute rheumatic fever (ARF) prevention, however clinical guidelines for prescription vary. GAS carriers with acute viral infections may receive antibiotics unnecessarily. This review assessed the prevalence of GAS pharyngitis and carriage in different settings.

Methods

A random-effects meta-analysis was performed. Prevalence estimates for GAS+ve pharyngitis, serologically-confirmed GAS pharyngitis and asymptomatic pharyngeal carriage were generated. Findings were stratified by age group, recruitment method and country income level. Medline and EMBASE databases were searched for relevant literature published between 1 January 1946 and 7 April 2017. Studies reporting prevalence data on GAS+ve or serologically-confirmed GAS pharyngitis that stated participants exhibited symptoms of pharyngitis or upper respiratory tract infection (URTI) were included. Included studies reporting the prevalence of asymptomatic GAS carriage needed to state participants were asymptomatic.

Results

285 eligible studies were identified. The prevalence of GAS+ve pharyngitis was 24.1% (95% CI: 22.6–25.6%) in clinical settings (which used ‘passive recruitment’ methods), but less in sore throat management programmes (which used ‘active recruitment’, 10.0%, 8.1–12.4%). GAS+ve pharyngitis was more prevalent in high-income countries (24.3%, 22.6–26.1%) compared with low/middle-income countries (17.6%, 14.9–20.7%). In clinical settings, approximately 10% of children swabbed with a sore throat have serologically-confirmed GAS pharyngitis, but this increases to around 50–60% when the child is GAS culture-positive. The prevalence of serologically-confirmed GAS pharyngitis was 10.3% (6.6–15.7%) in children from high-income countries and their asymptomatic GAS carriage prevalence was 10.5% (8.4–12.9%). A lower carriage prevalence was detected in children from low/middle income countries (5.9%, 4.3–8.1%).

Conclusions

In active sore throat management programmes, if the prevalence of GAS detection approaches the asymptomatic carriage rate (around 6–11%), there may be little benefit from antibiotic treatment as the majority of culture-positive patients are likely carriers.

Treating sore throats caused by Group A Streptococcus infections (GAS pharyngitis) with antibiotics is important for preventing acute rheumatic fever (ARF). It is impossible to distinguish patients with true GAS pharyngitis infections from GAS carriers with pharyngitis caused by viral infections when throat swab culturing alone is used to diagnose GAS pharyngitis. Carriers are not likely to benefit from antibiotic treatment, but may receive treatment unnecessarily. Reported rates of GAS pharyngitis and carriage vary considerably depending on the setting. Thus it is difficult to ascertain which groups are likely to benefit significantly from active sore throat management programmes which treat GAS pharyngitis in order to prevent ARF. We performed a meta-analysis to estimate the prevalence of GAS pharyngitis and asymptomatic carriage in different settings. Approximately 10% of all children swabbed for a sore throat in clinical settings have true GAS pharyngitis, but this increases to around 55% if the children have GAS detected in their throat using swab cultures. In active sore throat management programmes, the prevalence of GAS detection is lower than in clinical settings and if it declines towards 8% (the asymptomatic carriage level), there may be little benefit in treating GAS culture-positive patients with antibiotics.

Acute Rheumatic Fever After Group A Streptococcus Pyoderma and Group G Streptococcus Pharyngitis

A case of acute rheumatic fever (ARF) in an Indigenous Maori child in New Zealand after Group A Streptococcus pyoderma and Group G Streptococcus pharyngitis is reported. The case demonstrates that ARF can develop in the absence of GAS pharyngitis and highlights a need for further research into the role of pyoderma and non-Group A Streptococci infections in ARF pathogenesis.