BACKGROUND: The gradual replacement of the Streptococcus pyogenes M1global genotype by a newly emergent M1UK variant is a global public health threat warranting increased surveillance. M1UK differs from progenitor M1global genotype by 27 single nucleotide polymorphisms (SNPs) and is characterised by increased speA superantigen expression in vitro.
METHODS: An allele-specific real-time PCR assay was developed for the rapid detection of M1UK strains. The assay was used in combination with whole-genome sequencing to determine emm (sub)type distribution for 51 invasive (n = 9) and non-invasive (n = 42) S. pyogenes clinical isolates.
RESULTS: Emm1 was the most prevalent S. pyogenes emm serotype (n = 11) in this set of clinical isolates, with M1UK being the dominant emm1 genotype (4/5 invasive, 3/6 non-invasive isolates). The assay accurately detected M1UK strains. Whole genome sequencing revealed continued presence of Australian M1UK sub-lineages associated with epidemic scarlet fever-causing S. pyogenes in Asia.
CONCLUSIONS: Our study establishes a suitable target for detection of the toxigenic M1UK, and confirms the maintenance of M1UK strains in Queensland, Australia. This assay can be deployed in laboratories and provides a valuable, cost-effective tool to enhance surveillance of the expanding M1UK clone.

At the end of 2022 into early 2023, the UK Health Security Agency reported unusually high levels of scarlet fever and invasive disease caused by Streptococcus pyogenes (StrepA or group A Streptococcus). During this time, we collected and genome-sequenced 341 non-invasive throat and skin S. pyogenes isolates identified during routine clinical diagnostic testing in Sheffield, a large UK city. We compared the data with that obtained from a similar collection of 165 isolates from 2016 to 2017. Numbers of throat-associated isolates collected peaked in early December 2022, reflecting the national scarlet fever upsurge, while skin infections peaked later in December. The most common emm-types in 2022-2023 were emm1 (28.7 %), emm12 (24.9 %) and emm22 (7.7 %) in throat and emm1 (22 %), emm12 (10 %), emm76 (18 %) and emm49 (7 %) in skin. While all emm1 isolates were the M1UK lineage, the comparison with 2016-2017 revealed diverse lineages in other emm-types, including emm12, and emergent lineages within other types including a new acapsular emm75 lineage, demonstrating that the upsurge was not completely driven by a single genotype. The analysis of the capsule locus predicted that only 51 % of throat isolates would produce capsule compared with 78% of skin isolates. Ninety per cent of throat isolates were also predicted to have high NADase and streptolysin O (SLO) expression, based on the promoter sequence, compared with only 56% of skin isolates. Our study has highlighted the value in analysis of non-invasive isolates to characterize tissue tropisms, as well as changing strain diversity and emerging genomic features which may have implications for spillover into invasive disease and future S. pyogenes upsurges.

Since October 2022, alerts have spread from several countries about the increase in invasive group A streptococcal (iGAS) and scarlet fever cases affecting young children. We aim to analyze the epidemiology of GAS infections in the last 12 years in our hospital and identify the clinical features of invasive cases observed in 2023. We conducted a retrospective study enrolling children and adolescents hospitalized at our pediatric clinic from January to December 2023 for a definitive diagnosis of iGAS infection. Clinical, laboratory, and imaging data were collected and analyzed. Comparing 2016 and 2023, we observed a similar number of GAS infections (65 vs. 60 cases). Five children with iGAS infection were hospitalized between March and April 2023. The median age was five years. At admission, all patients showed tachycardia disproportionate to their body temperature. Vomiting was a recurrent symptom (80%). Laboratory tests mostly showed lymphopenia, hyponatremia, and high inflammatory markers. The number of pediatric iGAS cases significantly increased in 2023. Clinical (pre-school-aged children with high fever, unexplained tachycardia, and vomiting) and laboratory parameters (high procalcitonin levels, hyponatremia, and lymphopenia) could help identify and suspect a potential iGAS infection.

UNASSIGNED: Scarlet fever is an infectious disease caused by Streptococcus pyogenes. However, there is limited data regarding the disease in the Arab World, including the United Arab Emirates.
UNASSIGNED: To analyse a scarlet fever outbreak in United Arab Emirates.
UNASSIGNED: This retrospective cross-sectional study included scarlet fever cases diagnosed at the Kanad Hospital, Al Ain, United Arab Emirates in 2022 and 2023. Data were retrieved from the hospital records and analysed using SPSS version 23.0. Chi-Square, Mann-Whitney, and Monte Carlo tests were applied.
UNASSIGNED: Two hundred and twenty-two cases (13.5% in 2022 and 86.5% in 2023) were confirmed (P<0.001). Majority (67.1%) of the patients were aged 3-6 years, with a mean age of 4.56 ± 1.99 years. Rash, fever and sore throat were observed in 100%, 99.1%, and 82.0% of cases, respectively. The majority (85.1%) were managed as outpatients and 77.0% responded to oral penicillin. Patients\' age was not significantly associated with nonresponse to penicillin and in-hospital admission. The outbreak had winter and summer peaks, with the highest incidence occurring during January and February 2023.
UNASSIGNED: This study serves as a valuable reference for other studies, which should include antimicrobial susceptibility testing and the prevailing genetic variance of Streptococcus pyogenes.
تحليل وصفي لفاشية الحمى القرمزية في الإمارات العربية المتحدة.
إيمان خليفة صبح، ثياجاراج أديمولام كوماراسامي، زهراء خليفة صبح.
UNASSIGNED: ان الحُمَّى القرمزية مرض مُعدٍ تسببه المكورات العقدية المقيحة. ولكن توجد بيانات محدودة عن هذا المرض في العالم العربي، ومنه الإمارات العربية المتحدة.
UNASSIGNED: هدفت هذه الدراسة الى تحليل فاشية الحُمَّى القرمزية في الإمارات العربية المتحدة.
UNASSIGNED: شملت هذه الدراسة المقطعية الاسترجاعية حالات الحمى القرمزية التي شُخِّصت في مستشفى كند في مدينة العين بالإمارات العربية المتحدة في عامَي 2022 و2023. واستُُرجعت البيانات من سجلات المستشفى، وحُلِّلت ببرنامج SPSS، الإصدار 23.0. وطُبِّقت اختبارات مربع كاي، ومان ويتني، ومونت كارلو.
UNASSIGNED: رُصدت 222 حالة مؤكدة (13.5٪ منها في عام 2022 و86.5٪ في عام 2023) (القيمة الاحتمالية: P<0.001). وتراوحت أعمار غالبية المرضى (67.1٪) بين 3 و6 سنوات، وبلغ متوسط أعمارهم 4.56 ± 1.99 سنوات. ولُوحظت أعراض الطفح الجلدي والحمى والتهاب الحلق في 100٪ و99.1٪ و82.0٪ من الحالات على الترتيب. وقُدِّم العلاج لغالبية المرضى (85.1٪) في العيادات الخارجية، واستجاب 77.0٪ منهم للبنسلين الفموي. ولم ترتبط أعمار المرضى ارتباطًا ملحوظًا بعدم الاستجابة للبنسلين والحاجة إلى دخول المستشفى. وبلغت الفاشية ذروتها في الشتاء وفي الصيف، وحدثت أعلى معدلات الإصابة خلال شهرَي يناير/ كانون الثاني وفبراير/ شباط 2023.
UNASSIGNED: تعد هذه الدراسة مرجع قيِّم لدراسات أخرى، وهي الدراسات التي ينبغي أن تشمل اختبارات بشأن الحساسية لمضادات الميكروبات والتباين الجيني السائد للمكورات العقدية المقيحة.
Analyse rétrospective d’une flambée de scarlatine aux Émirats arabes unis.
UNASSIGNED: La scarlatine est une maladie infectieuse causée par Streptococcus pyogenes. Cependant, il existe peu de données à ce sujet dans le monde arabe, et notamment aux Émirats arabes unis.
UNASSIGNED: Analyser une flambée de scarlatine survenue aux Émirats arabes unis.
UNASSIGNED: La présente étude transversale rétrospective a inclus des cas de scarlatine diagnostiqués à l\'hôpital Kanad, à Al Ain, aux Émirats arabes unis en 2022 et 2023. Les données ont été extraites des dossiers d\'hôpital et analysées à l\'aide du logiciel SPSS version 23.0. Les tests de khi carré, de Mann-Whitney et de Monte-Carlo ont été appliqués.
UNASSIGNED: Deux cent vingt-deux cas (13,5 % en 2022 et 86,5 % en 2023) ont été confirmés (p<0,001). La majorité des patients (61,7 %) étaient âgés entre trois et six ans, l\'âge moyen étant de 4,56 ± 1,99 ans. Des éruptions cutanées, de la fièvre et des maux de gorge ont été observés dans 100 %, 99,1 % et 82 % des cas respectivement. La majorité des personnes touchées (85,1 %) ont été prises en charge en ambulatoire et 77,0 % ont répondu à la pénicilline par voie orale. L\'âge des patients n\'était pas significativement associé à la non-réponse à la pénicilline et à l\'hospitalisation. La flambée a connu des pics en hiver et en été, l\'incidence la plus élevée s\'étant produite en janvier et février 2023.
UNASSIGNED: Cette étude sert de référence précieuse pour d\'autres études, qui devraient inclure des tests de sensibilité aux antimicrobiens et la variance génétique prévalente de Streptococcus pyogenes.

As an acute respiratory disease, scarlet fever has great harm to public health. Some evidence indicates that the time distribution pattern of heavy PM2.5 pollution occurrence may have an impact on health risks. This study aims to reveal the relation between scaling features in high-concentrations PM2.5 (HC-PM2.5) evolution and scarlet fever incidence (SFI). Based on the data of Hong Kong from 2012 to 2019, fractal box-counting dimension (D) is introduced to capture the scaling features of HC-PM2.5. It has been found that index D can quantify the time distribution of HC-PM2.5, and lower D values indicate more cluster distribution of HC-PM2.5. Moreover, scale-invariance in HC-PM2.5 at different time scales has been discovered, which indicates that HC-PM2.5 occurrence is not random but follows a typical power-law distribution. Next, the exposure-response relationship between SFI and scale-invariance in HC-PM2.5 is explored by Distributed lag non-linear model, in conjunction with meteorological factors. It has been discovered that scale-invariance in HC-PM2.5 has a nonlinear effect on SFI. Low and moderate D values of HC-PM2.5 are identified as risk factors for SFI at small time-scale. Moreover, relative risk shows a decreasing trend with the increase of exposure time. These results suggest that exposure to short-term clustered HC-PM2.5 makes individual more prone to SFI than exposure to long-term uniform HC-PM2.5. This means that individuals in slightly-polluted regions may face a greater risk of SFI, once the PM2.5 concentration keeps rising. In the future, it is expected that the relative risk of scarlet fever for a specific region can be estimated based on the quantitative analysis of scaling features in high-concentrations PM2.5 evolution.

The UK observed a marked increase in scarlet fever and invasive group A streptococcal infection in 2022 with severe outcomes in children and similar trends worldwide. Here we report lineage M1UK to be the dominant source of invasive infections in this upsurge. Compared with ancestral M1global strains, invasive M1UK strains exhibit reduced genomic diversity and fewer mutations in two-component regulator genes covRS. The emergence of M1UK is dated to 2008. Following a bottleneck coinciding with the COVID-19 pandemic, three emergent M1UK clades underwent rapid nationwide expansion, despite lack of detection in previous years. All M1UK isolates thus-far sequenced globally have a phylogenetic origin in the UK, with dispersal of the new clades in Europe. While waning immunity may promote streptococcal epidemics, the genetic features of M1UK point to a fitness advantage in pathogenicity, and a striking ability to persist through population bottlenecks.

BACKGROUND: An accelerated epidemiological transition, spurred by economic development and urbanization, has led to a rapid transformation of the disease spectrum. However, this transition has resulted in a divergent change in the burden of infectious diseases between urban and rural areas. The objective of our study was to evaluate the long-term urban-rural disparities in infectious diseases among children, adolescents, and youths in China, while also examining the specific diseases driving these disparities.
RESULTS: This observational study examined data on 43 notifiable infectious diseases from 8,442,956 cases from individuals aged 4 to 24 years, with 4,487,043 cases in urban areas and 3,955,913 in rural areas. The data from 2013 to 2021 were obtained from China\'s Notifiable Infectious Disease Surveillance System. The 43 infectious diseases were categorized into 7 categories: vaccine-preventable, bacterial, gastrointestinal and enterovirus, sexually transmitted and bloodborne, vectorborne, zoonotic, and quarantinable diseases. The calculation of infectious disease incidence was stratified by urban and rural areas. We used the index of incidence rate ratio (IRR), calculated by dividing the urban incidence rate by the rural incidence rate for each disease category, to assess the urban-rural disparity. During the nine-year study period, most notifiable infectious diseases in both urban and rural areas exhibited either a decreased or stable pattern. However, a significant and progressively widening urban-rural disparity in notifiable infectious diseases was observed. Children, adolescents, and youths in urban areas experienced a higher average yearly incidence compared to their rural counterparts, with rates of 439 per 100,000 compared to 211 per 100,000, respectively (IRR: 2.078, 95% CI [2.075, 2.081]; p < 0.001). From 2013 to 2021, this disparity was primarily driven by higher incidences of pertussis (IRR: 1.782, 95% CI [1.705, 1.862]; p < 0.001) and seasonal influenza (IRR: 3.213, 95% CI [3.205, 3.220]; p < 0.001) among vaccine-preventable diseases, tuberculosis (IRR: 1.011, 95% CI [1.006, 1.015]; p < 0.001), and scarlet fever (IRR: 2.942, 95% CI [2.918, 2.966]; p < 0.001) among bacterial diseases, infectious diarrhea (IRR: 1.932, 95% CI [1.924, 1.939]; p < 0.001), and hand, foot, and mouth disease (IRR: 2.501, 95% CI [2.491, 2.510]; p < 0.001) among gastrointestinal and enterovirus diseases, dengue (IRR: 11.952, 95% CI [11.313, 12.628]; p < 0.001) among vectorborne diseases, and 4 sexually transmitted and bloodborne diseases (syphilis: IRR 1.743, 95% CI [1.731, 1.755], p < 0.001; gonorrhea: IRR 2.658, 95% CI [2.635, 2.682], p < 0.001; HIV/AIDS: IRR 2.269, 95% CI [2.239, 2.299], p < 0.001; hepatitis C: IRR 1.540, 95% CI [1.506, 1.575], p < 0.001), but was partially offset by lower incidences of most zoonotic and quarantinable diseases in urban areas (for example, brucellosis among zoonotic: IRR 0.516, 95% CI [0.498, 0.534], p < 0.001; hemorrhagic fever among quarantinable: IRR 0.930, 95% CI [0.881, 0.981], p = 0.008). Additionally, the overall urban-rural disparity was particularly pronounced in the middle (IRR: 1.704, 95% CI [1.699, 1.708]; p < 0.001) and northeastern regions (IRR: 1.713, 95% CI [1.700, 1.726]; p < 0.001) of China. A primary limitation of our study is that the incidence was calculated based on annual average population data without accounting for population mobility.
CONCLUSIONS: A significant urban-rural disparity in notifiable infectious diseases among children, adolescents, and youths was evident from our study. The burden in urban areas exceeded that in rural areas by more than 2-fold, and this gap appears to be widening, particularly influenced by tuberculosis, scarlet fever, infectious diarrhea, and typhus. These findings underscore the urgent need for interventions to mitigate infectious diseases and address the growing urban-rural disparity.

暂无摘要。

Contagious exanthematous diseases are becoming a major public health problem. The purpose of this study was to evaluate the potential epidemiological trend of four infectious exanthematous diseases in Italy through the searches on the internet.
We used the following Italian search term: \'Sesta malattia\' (Sixth Disease, in English), \'Eritema Infettivo\' (also knows \'Quinta malattia\' in Italian; Fifth Disease in English), \'Quarta malattia\' (Fourth Disease in English) and \'Scarlattina\' (Scarlet fever in English). We overlapped Google Trends and Wikipedia data to perform a linear regression and correlation analysis. Statistical analyses were performed using the Spearman\'s rank correlation coefficient (rho). The study period is between July 2015 and December 2022.
The diseases considered have a seasonal trend and the search peaks between GT and Wikipedia overlap. A temporal correlation was observed between GT and Wikipedia search trends. Google Trends Internet search data showed strong correlation with Wikipedia with a rho statistically significant for Fifth disease (rho = 0.78), Fourth disease (rho = 0.76) and Scarlet-fever (rho = 0.77), moderate correlation for Sixth disease (rho = 0.32).
Infectious disease searches using Google and Wikipedia can be useful for public health surveillance and help policy makers implement prevention and information programs for the population, in addition to the fact that increases in searches could represent an early warning in the detection of outbreaks.

Notifications of invasive group A streptococcal (iGAS) infections have significantly increased in many European Countries compared to the previous season. In Italy, there has been an increase in streptococcal pharyngitis and scarlet fever cases since January 2023, which sparked concerns about a GAS epidemic in the pediatric population. This rise may be ascribed to the GAS infection season that began earlier than usual (off-season outbreak) and the increase in the spread of respiratory viruses and viral coinfections that raised the risk of iGAS disease. Moreover, this phenomenon was also facilitated by increased travel after reduced GAS circulation during the COVID-19 pandemic.The increase in cases of GAS disease has raised some critical issues regarding the potential reactions to administering amoxicillin, the first-line antibiotic therapy, many of which have been erroneously labeled as \"allergy.\"For these reasons, the Italian Society of Pediatric Allergy and Immunology (SIAIP) intends to provide simple clinical indications to help pediatricians manage GAS pharyngitis, discerning the allergic from non-allergic drug hypersensitivity.