Point-of-Care Testing in Primary Care

Point-of-care testing (POCT) in pediatric primary care is essential for clinicians to make a timely and accurate diagnosis. The COVID-19 pandemic has highlighted the importance of timely and accurate testing strategies to correctly identify the etiology of upper and lower respiratory infections. Additionally, pediatric POCT continues to be important in rural and underserved communities where access to hospital laboratories may be less available. This chapter will focus on seven rapid tests: Group A streptococcus (GAS), influenza A & B, SARS-CoV-2 (COVID-19), human immunodeficiency virus (HIV), C-reactive protein (CRP), human chorionic gonadotropin (hCG), and hemoglobin A1c (HbA1c). © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.

Emerging Invasive Group A Streptococcus M1UK Lineage Detected by Allele-Specific PCR, England, 20201.

Increasing reports of invasive Streptococcus pyogenes infections mandate surveillance for toxigenic lineage M1UK. An allele-specific PCR was developed to distinguish M1UK from other emm1 strains. The M1UK lineage represented 91% of invasive emm1 isolates in England in 2020. Allele-specific PCR will permit surveillance for M1UK without need for genome sequencing.

Epidemiology of Respiratory Infections during the COVID-19 Pandemic.

To face the COVID-19 outbreak, a wide range of non-pharmaceutical interventions (NPIs) aimed at limiting the spread of the virus in communities, such as mask-wearing, hand hygiene, social distancing, travel restrictions, and school closures, were introduced in most countries. Thereafter, a significant reduction of new asymptomatic and symptomatic COVID-19 cases occurred, although there were differences between countries according to the type and duration of the NPIs. In addition, the COVID-19 pandemic has been accompanied by significant variations in the global incidence of diseases due to the most common non-SARS-CoV-2 respiratory viruses and some bacteria. In this narrative review, the epidemiology of the most common non-SARS-CoV-2 respiratory infections during the COVID-19 pandemic is detailed. Moreover, factors that could have had a role in modifying the traditional circulation of respiratory pathogens are discussed. A literature analysis shows that NPIs were the most important cause of the general reduction in the incidence of influenza and respiratory syncytial virus infection in the first year of the pandemic, although the different sensitivity of each virus to NPIs, the type and duration of measures used, as well as the interference among viruses may have played a role in modulating viral circulation. Reasons for the increase in the incidences of Streptococcus pneumoniae and group A Streptococcus infections seem strictly linked to immunity debt and the role played by NPIs in reducing viral infections and limiting bacterial superimposed infections. These results highlight the importance of NPIs during pandemics, the need to monitor the circulation of infectious agents that cause diseases similar to those caused by pandemic agents, and the need to make efforts to improve coverage with available vaccines.

Surveillance of noninvasive group A Streptococcus infections in French ambulatory pediatrics before and during the COVID-19 pandemic: a prospective multicenter study from 2018-2022.

OBJECTIVES: We evaluated the burden of noninvasive group A Streptococcus (GAS) infections in ambulatory pediatrics before and during the COVID-19 pandemic in France. METHODS: We analyzed data from a national network of ambulatory pediatricians between 2018 and 2022. Clinicians evaluating children ≤15 years old for tonsillopharyngitis, perianal infections, paronychia/blistering dactylitis, and scarlet fever were invited to perform a rapid antigen detection test (RADT) for GAS. Monthly incidence of noninvasive GAS infections per 10,000 visits was modeled using time series analysis, considering two breakpoints: March 2020 (first national lockdown) and March 2022 (end of mandatory mask-wearing in schools). RESULTS: Over the study period, 125 pediatricians recorded 271,084 infectious episodes. GAS-related illnesses represented 4.3% of all infections. In March 2020, the incidence of GAS diseases decreased by 84.5% (P <0.001), with no significant trend until March 2022. After March 2022, the incidence significantly increased (+23.8% per month, P <0.001), with similar patterns across all monitored GAS-related diseases. CONCLUSION: By using routine clinical data and RADTs, we have monitored changes in the incidence of noninvasive GAS infections in ambulatory pediatrics. COVID-19 mitigation measures have had a major impact on the epidemiology of noninvasive GAS infections, but their relaxation was followed by a surge above baseline levels.

[Paying attention to the epidemic of group A Streptococcus infections in multiple European and American countries]. / å ³æ³¨æ¬§ç¾Žå¤šå›½Aæ—é“¾çƒèŒæ„ŸæŸ“ç–«æƒ .

At the end of 2022, the World Health Organization reported an increase in group A Streptococcus (GAS) infections, such as scarlet fever, in multiple countries. The outbreak primarily affected children under 10 years old, and the number of deaths was higher than anticipated, causing international concern. This paper reviews the current state of the GAS disease outbreak, its causes, and response measures. The authors aim to draw attention from clinical workers in China and increase their awareness and vigilance regarding this epidemic. Healthcare workers should be aware of the potential epidemiological changes in infectious diseases that may arise after the optimization of control measures for coronavirus disease 2019 to ensure children's health.

Peculiarities of Periodontal Pocket Microbiome in Patients with Generalized Periodontitis in the Post-Covid Period

The oral cavity, like the lungs, is often referred to as the <<ecological niche of commensal, symbiotic, and pathogenic or-ganisms,>> and the emigration and elimination of microbes between them are constant, ensuring a healthy distribution of saprophytic microorganisms that maintains organ, tissue, and immune homeostasis. The prolonged hospital stays due to COVID-19 complications, cross-infection, oxygenation therapy through the mask or incubation, and long-term intravenous infusions limit the patient's ability to care about the oral cavity, regularly clean teeth, floss interdental, etc., which creates extremely favorable conditions for colonization by aerobic and anaerobic pathogens of the oral cavity and periodontal pockets and leads to the rapid progression of chronic generalized periodontitis in this category of patients in the future. The goal of the study was to assess the state of the microbiome of the periodontal pockets of dental patients in the post-covid period. Methods. The object of the study was 140 patients with generalized periodontitis of the I and II stages of development in the chronic course (GP), among which 80 patients had coronavirus disease in the closest past. The patients were randomized by age, sex, and stage of GP development. The diagnosis of periodontal disease was established according to the classification by Danilevskyi. The bacteriological material for aerobic and facultative anaerobic microflora and yeast-like fungi was collected from periodontal pockets with a calibrated bacteriological loop and immediately seeded on blood agar. Results. Significant qualitative and quantitative changes in the nature of the oral microbiocenosis were observed in patients with GP after the recent coronavirus disease, compared with similar patients who did not suffer from COVID-19. We have noticed almost complete disappearance of bacteria that belong to the transient representatives of the oral microflora such as Neisseria, corynebacteria (diphtheria), micrococci, and lac-tobacilli. The main resident representatives of the oral microflora, i.e., alpha-hemolytic Streptococci of the mitis group, were found in all healthy individuals and patients of groups A and C, but in 30.0 +/- 4.58% of patients in group B, alpha-hemolytic streptococci in the contents of periodontal pockets are present in quantities not available for detection by the applied method (<2.7 lg CCU/mL). In terms of species, Streptococcus oralis and Streptococcus salivarius are more characteris-tic in gingival crevicular fluid in healthy individuals (93.8% of selected strains). In 68.4 +/- 3.32% of patients in group A, 64.0 +/- 3.43% of patients in group B, and 67.5 +/- 3.76% of patients in group C, the dominant species were Streptococcus gordonii and Streptococcus sanguinis (p<0.01), which increased pathogenic potential as they produce streptolysin-O, inhibit complement activation, bind to fibronectine, actively form biofilms on the surface of tooth enamel and gum epithelial surface, and can act as an initiator of adhesion of periodontal pathogens. The other representatives of the resident microflora of the oral cavity - Stomatococcus mucilaginosus and Veillonella parvula for the patients of group C are also found in periodontal pockets with a significantly lower index of persistence and minimal population level. In the post-covid period, both the population level and the frequency of colonization of periodontal pockets by Staphylo-cocci and beta-hemolytic Streptococci decreases rapidly. For these patient groups, unlike for those that did not suffer from COVID-19, we did not find any case of colonization with Staphylococcus aureus, as well as beta-hemolytic Streptococci and Epidermal staphylococcus were also absent. The most characteristic in the post-covid period is a decrease in the proportion of alpha-hemolytic Streptococci, an increase in the proportion of yeast-like fungi of Candida species, as well as the appearance of a significant number of gram-negative rod-shaped bacteria (Enterobacteria and Pseudomonads). In periodontal patien s, the microbial count is approximately 2 orders of magnitude lower than in those with GP who did not suffer from COVID-19 (p<0.05). Conclusions. The overpassed coronavirus disease due to intensive antibiotic therapy leads to a marked decrease in the number of viable saprophytic microorganisms in the periodontal pockets of patients with GP. In the post-covid period for the patients with GP, there is a decrease in the level of colonization of periodontal pockets by species of resident oral microflora - alpha-hemolytic Streptococci, reduction of resident micro-organism's species, and almost complete disappearance of transient microflora. On the other hand, the frequency of colonization of periodontal pockets by fungi species, enterobacteria, and pseudomonads significantly increases. There are more expressed disorders in the periodontal pocket's microbiome for the patients with a severe and complicated course of coronavirus disease, such as post-covid pulmonary fibrosis, which requires reconsideration of approaches to therapeutic and pharmacological treatment in this category of patients.Copyright © 2022, Zabolotny Institute of Microbiology and Virology, NAS of Ukraine. All rights reserved.

Group A Streptococcus Necrotizing Lymphadenitis: A Case Report.

Necrotizing lymphadenitis (NL) is a rare entity that can occur as a complication of bacterial cervical lymphadenitis (CL) and is characterized by unilateral or bilateral cervical lymphadenopathy. NL most commonly presents in females and most reports have been in Japan. In this case, we present a 37-year-old male with no significant past medical history who presented with an unusual presentation and clinical course of NL. Initial workup for Epstein-Barr Virus (EBV) and other infectious etiology was negative. Yet, aspiration later revealed Group A Streptococcus. When the patient's pain and swelling did not subside with the initial antibiotic and supportive treatment, the patient underwent a repeat aspiration and biopsy that revealed a necrotic mass or lymph node. NL is uncommon and rarely due to infectious etiology. However, this marks a case in which a Group A Streptococcus was shown to be associated with subsequent necrotic lymph nodes and should allow practitioners to further consider an infectious etiology in the differential diagnosis of NL.

Epidemiological analysis of Group A streptococcus infection diseases among children in Beijing, China under COVID-19 pandemic.

BACKGROUND: Group A streptococcus is human-restricted gram-positive pathogen, responsible for various clinical presentations from mild epidermis infections to life threatened invasive diseases. Under COVID-19 pandemic,. the characteristics of the epidemic strains of GAS could be different. PURPOSE: To investigate epidemiological and molecular features of isolates from GAS infections among children in Beijing, China between January 2020 and December 2021. Antimicrobial susceptibility profiling was performed based on Cinical Laboratory Sandards Institute. Distribution of macrolide-resistance genes, emm types, and superantigens was examined by polymerase chain reaction. RESULTS: 114 GAS isolates were collected which were frequent resistance against erythromycin (94.74%), followed by clindamycin (92.98%), tetracycline (87.72%). Emm12 (46.49%), emm1 (25.44%) were dominant emm types. Distribution of ermB, ermA, and mefA gene was 93.85%, 2.63%, and 14.04%, respectively. Frequent superantigenes identified were smeZ (97.39%), speG (95.65%), and speC (92.17%). Emm1 strains possessed smeZ, ssa, and speC, while emm12 possessed smeZ, ssa, speG, and speC. Erythromycin resistance was predominantly mediated by ermB. Scarlet fever strains harbored smeZ (98.81%), speC (94.05%). Impetigo strains harbored smeZ (88.98%), ssa (88.89%), and speC (88.89%). Psoriasis strains harbored smeZ (100%). CONCLUSIONS: Under COVID-19 pandemic, our collections of GAS infection cutaneous diseases decreased dramatically. Epidemiological analysis of GAS infections among children during COVID-19 pandemic was not significantly different from our previous study. There was a correlation among emm, superantigen gene and disease manifestations. Long-term surveillance and investigation of emm types and superantigens of GAS prevalence are imperative.

Macromolecular crowding agents enhance the sensitivity of lateral flow immunoassays.

Lateral flow immunoassays (LFIA) have a plethora of applications in health, environmental and food sectors for low-cost, simple, and rapid point-of-need testing. Typically, the user only needs to add the sample without any other intervention from sample application to results. A compelling challenge, and a constant pursuit in LFIA is to improve the assay sensitivity without compromising the simplicity and practicality. We report that the addition of water-soluble macromolecular crowding agents leads to an enhancement of the sensitivity, which is attributed to the fact that the exposure of antibodies and micro/nanoparticle conjugates to macromolecularly crowded environment, while migrating through the confining pores of the strip-pads by capillary forces, promotes the interactions that are responsible for analyte recognition and signal generation. The effect was shown by using two of the most widely established LFIA tests worldwide, that is, detection of nucleocapsid protein from SARS-CoV-2 associated with COVID-19 and detection of Strep-A antigen from Streptococcus pyogenes associated with pharyngitis. For immediate demonstration of the sensitivity enhancement, we worked directly on commercially available devices already optimized in terms of reagents and conditions. Of the crowders used, ficoll, Mr 400000, and ficoll, Mr 70000, gave a 5-10-fold improvement of the signal without affecting the background. Because the addition of macromolecular crowding agents is complementary to other strategies of sensitivity enhancement, such as the design of novel labels and the introduction of signal amplification, we anticipate that the proposed modulation will be extended to numerous analytes with a variety of reporters and LFIA configurations.

On race, human variation, and who gets and dies of sepsis

COVID-19 has highlighted a brutal reality known for decades, that Black, Indigenous, and People of Color bear a disproportionate burden of US annual sepsis cases. While plentiful research funds have been spent investigating genetic reasons for racial disparities in sepsis, an abundance of research shows that sepsis incidence and mortality maps to indicators of colonial practices including residential segregation, economic and marginalization sepsis, and denial of care. Here we argue that sepsis risk is an immunological embodiment of racism in colonial states, that the factors contributing to sepsis disparities are insidious and systemic. We show that regardless of causative pathogen, or host ancestry, racialized people get and die of sepsis most frequently in a pattern repeatedly reiterated worldwide. Lastly, we argue that while alleviation of sepsis disparities requires radical, multiscale intervention, biological anthropologists have a responsibility in this crisis. While some of us can harness our expertise to take on the ground action in sepsis prevention, all of us can leverage our positions as the first point of contact for in depth human biology instruction on most college campuses. As a leading cause of death worldwide, and a syndrome that exhibits the interplay between human physiology, race and environment, sepsis is at the nexus of major themes in biological anthropology and is a natural fit for the field's curriculum. In adopting a discussion of race and sepsis in our courses, we not only develop new research areas but increase public awareness of both sepsis and the factors contributing to uneven sepsis burden.

Lactobacillus crispatus DSM25988 as novel bioactive agent to co-aggregate Streptococcus pyogenes and to exclude it by binding to human cells.

Streptococcus pyogenes, a group A streptococcus, is the major bacterial pathogen responsible for acute bacterial infection of the human oropharynx and the causative agent of scarlet fever. Estimates of the global burden of S. pyogenes related diseases revealed 616 million cases of pharyngitis, and at least 517,000 deaths due to severe invasive diseases and sequelae. Here we describe Lactobacillus crispatus DSM25988 that was identified among hundreds of Lactobacillus strains (referring to all organisms that were classified as Lactobacillaceae until 2020) showing ability to prevent adhesion of S. pyogenes to Detroit 562 cells, and to exhibit a masking and co-aggregating effect on S. pyogenes in vitro. L. crispatus DSM25988 also inhibits invasion of cultured human epithelial pharyngeal cells by S. pyogenes. Competitive binding to fibronectin might be involved in the inhibition process. Antiviral activity of the L. crispatus DSM25988 cells were identified in an in vitro cell model demonstrating that L. crispatus effectively excludes viruses from epithelial cells using SARS-CoV2 proteins as a model. This finding points to the potential of DSM25988 to protect cells from virus infection. Biological activity is retained in heat treated cells. The heat-treated Lactobacillus strain was further developed into functional throat lozenges, wherein its biological activity is stably maintained in the formulation. Lozenges containing L. crispatus DSM25988 underwent testing in an uncontrolled, prospective user study in 44 subjects with symptoms of sore throat for a period of up to 14 days. The study data shows promising safety and efficacy of the medical device when used against symptoms of sore throat like scratchy feeling, hoarse voice and swallowing pain.

Use of the McIsaac Score to Predict Group A Streptococcal Pharyngitis in Outpatient Nurse Phone Triage and Electronic Visits Compared With In-Person Visits: Retrospective Observational Study.

BACKGROUND: The McIsaac criteria are a validated scoring system used to determine the likelihood of an acute sore throat being caused by group A streptococcus (GAS) to stratify patients who need strep testing. OBJECTIVE: We aim to compare McIsaac criteria obtained during face-to-face (f2f) and non-f2f encounters. METHODS: This retrospective study compared the percentage of positive GAS tests by McIsaac score for scores calculated during nurse protocol phone encounters, e-visits (electronic visits), and in person f2f clinic visits. RESULTS: There was no difference in percentages of positive strep tests between encounter types for any of the McIsaac scores. There were significantly more phone and e-visit encounters with any missing score components compared with f2f visits. For individual score components, there were significantly fewer e-visits missing fever and cough information compared with phone encounters and f2f encounters. F2f encounters were significantly less likely to be missing descriptions of tonsils and lymphadenopathy compared with phone and e-visit encounters. McIsaac scores of 4 had positive GAS rates of 55% to 68% across encounter types. There were 4 encounters not missing any score components with a McIsaac score of 0. None of these 4 encounters had a positive GAS test. CONCLUSIONS: McIsaac scores of 4 collected during non-f2f care could be used to consider empiric treatment for GAS without testing if significant barriers to testing exist such as the COVID-19 pandemic or geographic barriers. Future studies should evaluate further whether non-f2f encounters with McIsaac scores of 0 can be safely excluded from GAS testing.

A Case of Co-occurrence of COVID-19 and Group A Streptococcal Pharyngitis.

Coronavirus disease 2019 (COVID-19) has swept the world with over hundred million of cases and millions of deaths. Upper respiratory tract symptoms including acute pharyngitis are the common symptoms of COVID-19, with a reported incidence of about 5%-17.4%. Group A Streptococcus (GAS) pharyngitis is a common cause of bacterial pharyngitis, with highest incidence between age 5 and 15, and it can still occur in adults with peak incidence at age 40. Herein, we report a case of co-occurrence of GAS and COVID-19 in a middle-aged man who presented with fever, sore throat, cough, and runny nose. To the best of our knowledge, we are the first to report this unique co-occurrence. Our case report aimed to raise the awareness among physician particularly in ambulatory and emergency department of not to have a singular focus on COVID-19 and forget to screen patient with acute pharyngitis for GAS.