ABSTRACT
Background. The COVID-19 pandemic has affected respiratory disease epidemiology. Measures to reduce transmission of SARS-CoV-2 (e.g., masking, social distancing, school closures) have reduced the incidence of common infectious diseases. At least one early report described changes in rates of pediatric GAS pharyngitis. We sought to determine the difference in GAS pharyngitis rates before and after the onset of the pandemic at our children's hospital. Methods. Clinical pharyngeal specimens tested for GAS by rapid antigen tests (RADTs) or LAMP methodology (loop-mediated isothermal amplification of GAS DNA) from January 2019 to March 2022 at our children's hospital were analyzed. Clinician's evaluating patients for GAS pharyngitis perform a RADT, when positive the patient is treated for GAS pharyngitis. When the RADT is negative, a LAMP test is performed. Patients were considered test-positive if either test was positive regardless of clinical symptoms. Annual positivity rates were compared using statistical process control (SPC) charts with both 2019 and 2020 as baseline years (i.e., 2019 vs 2020-3/2022;2020 vs 2021-3/2022). The change in GAS incidence rate (positive patients/ 1000 tested) between years was assessed by chi-square tests. Results. 9,896 patients had throat swabs tested for GAS from January 2019 through March 2022. Using SPC with 2019 as a baseline, there was a 15.1% decrease in mean GAS positivity through 3/2022. With 2020 as baseline, there was a 13.0% decrease in mean GAS positivity through 3/2022. The incidence of positive GAS tests decreased significantly: 2019 vs. 2020-3/2022 (x2 = 84.97, p <=0.00001) and 2020 vs. 2021-3/2022 (x2 = 154.01, p <=0.00001). Figure 1. Conclusion. Using throat swab results, the incidence of pediatric GAS pharyngitis at our hospital has decreased significantly during the COVID-19 pandemic. Implications: Pandemic-related riskmitigationmeasures, such asmasking, social distancing, and school closures, were associated with significantly decreased incidence of GAS pharyngitis. It is likely that GAS colonization and invasive infections were also affected.
ABSTRACT
Background. COVID-19 affected the epidemiology ofmany respiratory pathogens including GAS. Assessing genetic heterogeneity (emmtype, antimicrobial resistance, virulence factors) can inform treatment recommendations and targets for potential GAS vaccines. We assessed GAS clinical antibiotic susceptibility and performed whole genome sequencing (WGS) among pediatric pharyngeal isolates from 2020-2022. Methods. From 1/2020-3/2022 we collected throat swabs in pediatric clinics and EDs from children aged 3-18 years in Chicago, IL;Atlanta, GA;Portland, OR;and Phoenix, AZ: 1) with acute GAS pharyngitis and 2) among a convenience sample of asymptomatic children to assess for GAS colonization. Swabs were plated on blood agar. E-tests were used to assess clinical susceptibility to erythromycin (ERY) and ciprofloxacin (CIP). emm type and antimicrobial resistance genes (ERY, Clindamycin (CLI), and fluoroquinolones) were assessed by WGS. Results. 1144 pharyngeal swabs were collected: 359/684 (52%) from children with GAS pharyngitis by rapid test and 20/460 (4.3%) from asymptomatic children yielded GAS on culture. Phenotypic resistance: 55/364 (15%) tested isolates were ERY resistant and 5/364 (1.4%) CIP resistant. The proportion of isolates with ERY resistance increased significantly from 2020 (6%) to 2021-2022 (25%) (chi2 = 23.70, p< .00001) (Figure 1). MICs were high among ERY resistant GAS (Table 1). Genotypic resistance: Of 304 sequenced GAS isolates 40/304 (13%) were ERY resistant, 35/304 (11.5%) were both ERY resistant and CLI (inducible or constitutive) resistant, and 4/304 (1.3%) fluoroquinolone resistant. ermB (62%) was the most common gene for ERY resistance and constitutive CLI resistance, followed by ermTR (23%) and ermT (11%) both conferring inducible CLI resistance. Among the 20 isolates from asymptomatic children no ERY, CLI, or CIP resistance occurred, and no resistance genes were identified. emm types 11, 9, 77, 58 and 94 were associated with ERY and CLI resistance. Conclusion. ERY resistance increased from 2020-2022. The high rate of CLI resistance among ERY resistant GAS was associated with erm genes. These results are important to inform treatment recommendations for GAS pharyngitis and targets for vaccine development that can reduce antimicrobial-resistant GAS disease.
ABSTRACT
Our knowledge regarding chemical structure and properties of heparin and its derivatives, including biological properties in blood plasma, on the cell surface and while interacting with receptors, has been progressively growing. New insights are followed by the expansion of therapeutic opportunities and indications for the use of heparins. There are prerequisites for the creation of new generation drugs with modified properties that reduce a bleeding risk while applied for a non-anticoagulant goal. The non-anticoagulant heparin properties allow to consider it as a candidate for pathogenetic treatment of patients with COVID-19. This review focuses on the anticoagulant and non-anticoagulant heparin properties as well as the underlying molecular mechanisms.