SARS-CoV-2 Variants May Affect Saliva RT-PCR Assay Sensitivity.

BACKGROUND: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants demonstrate predilection for different regions of the respiratory tract. While saliva-based reverse transcription-polymerase chain reaction (RT-PCR) testing is a convenient, cost-effective alternative to nasopharyngeal swabs (NPS), few studies to date have investigated whether saliva sensitivity differs across variants of concern. METHODS: SARS-CoV-2 RT-PCR was performed on paired NPS and saliva specimens collected from individuals with acute coronavirus disease 2019 (COVID-19) symptoms or exposure to a COVID-19 household contact. Viral genome sequencing of NPS specimens and Los Angeles County surveillance data were used to determine the variant of infection. Saliva sensitivity was calculated using NPS-positive RT-PCR as the reference standard. Factors contributing to the likelihood of saliva SARS-CoV-2 RT-PCR positivity were evaluated with univariate and multivariable analyses. RESULTS: Between June 2020 and December 2022, 548 saliva samples paired with SARS-CoV-2 positive NPS samples were tested by RT-PCR. Overall, saliva sensitivity for SARS-CoV-2 detection was 61.7% (95% CI, 57.6%-65.7%). Sensitivity was highest with Delta infection (79.6%) compared to pre-Delta (58.5%) and Omicron (61.5%) (P = 0.003 and 0.01, respectively). Saliva sensitivity was higher in symptomatic individuals across all variants compared to asymptomatic cases [pre-Delta 80.6% vs 48.3% (P < 0.001), Delta 100% vs 72.5% (P = 0.03), Omicron 78.7% vs 51.2% (P < 0.001)]. Infection with Delta, symptoms, and high NPS viral load were independently associated with 2.99-, 3.45-, and 4.0-fold higher odds of SARS-CoV-2 detection by saliva-based RT-PCR (P = 0.004, <0.001, and <0.001), respectively. CONCLUSIONS: As new variants emerge, evaluating saliva-based testing approaches may be crucial to ensure effective virus detection.

Detection of SARS-CoV-2-Specific Secretory IgA and Neutralizing Antibodies in the Nasal Secretions of Exposed Seronegative Individuals.

Mucosal immunity may contribute to clearing SARS-CoV-2 infection prior to systemic infection, thereby allowing hosts to remain seronegative. We describe the meaningful detection of SARS-CoV-2-specific nasal mucosal antibodies in a group of exposed-household individuals that evaded systemic infection. Between June 2020 and February 2023, nasopharyngeal swab (NPS) and acute and convalescent blood were collected from individuals exposed to a SARS-CoV-2-confirmed household member. Nasal secretory IgA (SIgA) antibodies targeting the SARS-CoV-2 spike protein were measured using a modified ELISA. Of the 36 exposed individuals without SARS-CoV-2 detected by the RT-PCR of NPS specimens and seronegative for SARS-CoV-2-specific IgG at enrollment and convalescence, 13 (36.1%) had positive SARS-CoV-2-specific SIgA levels detected in the nasal mucosa at enrollment. These individuals had significantly higher nasal SIgA (median 0.52 AU/mL) compared with never-exposed, never-infected controls (0.001 AU/mL) and infected-family participants (0.0002 AU/mL) during the acute visit, respectively (both p < 0.001). The nasal SARS-CoV-2-specific SIgA decreased rapidly over two weeks in the exposed seronegative individuals compared to a rise in SIgA in infected-family members. The nasal SARS-CoV-2-specific SIgA may have a protective role in preventing systemic infection.

Defining the value of medical microbiology consultation.

Medical microbiologists, defined as doctoral-level laboratory directors with subspecialty training in medical microbiology, lead the clinical laboratory operations through activities such as clinical consultations, oversight of diagnostic testing menu, institutional leadership, education, and scholastic activities. However, unlike their clinical colleagues, medical microbiologists are largely unable to bill for clinical consultations performed within the hospital and, therefore, unable to generate relative value units or a similar quantifiable metric. As hospital budgets tighten and justification of staffing becomes a necessity, this may present a challenge to the medical microbiologist attempting to prove their value to the organization. To aid in providing tangible data, the Personnel Standards and Workforce subcommittee of the American Society for Microbiology conducted a multi-center study across seven medical centers to document clinical consultations and their impact. Consults were generated equally from internal (laboratory-based) and external (hospital-based) parties, with the majority directly impacting patient management. Near universal acceptance of the medical microbiologist's recommendation highlights the worth derived from their expertise. External consults required more time commitment from the medical microbiologist than internal consults, although both presented ample opportunity for secondary value, including impact through stewardship, education, clinical guidance, and cost reduction. This study is a description of the content and impact of consultations that underscore the importance of the medical microbiologist as a key member of the healthcare team. IMPORTANCE: Medical microbiologists are invaluable to the clinical microbiology laboratory and the healthcare system as a whole. However, as medical microbiologists do not regularly generate relative value units, capturing and quantifying the value provided is challenging. As hospital budgets tighten, justification of staffing becomes a necessity. To aid in providing tangible data, the Personnel Standards and Workforce subcommittee of the American Society for Microbiology conducted a multi-center study across seven medical centers to document clinical consultations and their impact. To our knowledge, this is the first study to provide detailed evaluation of the consultative value provided by medical microbiologists.

Guidelines on the use of sex and gender in cardiovascular research.

In cardiovascular research, sex and gender have not typically been considered in research design and reporting until recently. This has resulted in clinical research findings from which not only all women, but also gender-diverse individuals have been excluded. The resulting dearth of data has led to a lack of sex- and gender-specific clinical guidelines and raises serious questions about evidence-based care. Basic research has also excluded considerations of sex. Including sex and/or gender as research variables not only has the potential to improve the health of society overall now, but it also provides a foundation of knowledge on which to build future advances. The goal of this guidelines article is to provide advice on best practices to include sex and gender considerations in study design, as well as data collection, analysis, and interpretation to optimally establish rigor and reproducibility needed to inform clinical decision-making and improve outcomes. In cardiovascular physiology, incorporating sex and gender is a necessary component when optimally designing and executing research plans. The guidelines serve as the first guidance on how to include sex and gender in cardiovascular research. We provide here a beginning path toward achieving this goal and improve the ability of the research community to interpret results through a sex and gender lens to enable comparison across studies and laboratories, resulting in better health for all.

Clinical Impact of Multiplex Molecular Diagnostic Testing in Children With Acute Gastroenteritis Presenting to an Emergency Department: A Multicenter Prospective Study.

BACKGROUND: Multiplex molecular diagnostic panels have greatly enhanced detection of gastrointestinal pathogens. However, data on the impact of these tests on clinical and patient-centered outcomes are limited. METHODS: We conducted a prospective, multicenter, stepped-wedge trial to determine the impact of multiplex molecular testing at 5 academic children's hospitals on children presenting to the emergency department with acute gastroenteritis. Caregivers were interviewed on enrollment and 7-10 days after enrollment to determine symptoms, risk factors, subsequent medical visits, and impact on family members. During the pre-intervention period, diagnostic testing was performed at the clinician's discretion . During the intervention period, multiplex molecular testing was performed on all children, with results available to clinicians. The primary outcome was return visits to a healthcare provider within 10 days of enrollment. RESULTS: Potential pathogens were identified by clinician-ordered tests in 19 of 571 (3.3%) in the pre-intervention period compared with 434 of 586 (74%) in the intervention period; clinically relevant pathogens were detected in 2.1% and 15%, respectively. In the multivariate model, the intervention was associated with a 21% reduction in the odds of any return visit (odds ratio, 0.79; 95% confidence interval, .70-.90) after adjusting for potential confounders. Appropriate treatment was prescribed in 11.3% compared with 19.6% during the intervention period (P = .22). CONCLUSIONS: Routine molecular multiplex testing for all children who presented to the ED with acute gastroenteritis detected more clinically relevant pathogens and led to a 21% decrease in return visits. Additional research is needed to define patients most likely to benefit from testing. Clinical Trials Registration. NCT02248285.

Distinct hypoxia-induced translational profiles of embryonic and adult-derived macrophages.

Tissue resident macrophages are largely of embryonic (fetal liver) origin and long-lived, while bone marrow-derived macrophages (BMDM) are recruited following an acute perturbation, such as hypoxia in the setting of myocardial ischemia. Prior transcriptome analyses identified BMDM and fetal liver-derived macrophage (FLDM) differences at the RNA expression level. Posttranscriptional regulation determining mRNA stability and translation rate may override transcriptional signals in response to hypoxia. We profiled differentially regulated BMDM and FLDM transcripts in response to hypoxia at the level of mRNA translation. Using a translating ribosome affinity purification (TRAP) assay and RNA-seq, we identified non-overlapping transcripts with increased translation rate in BMDM (Ly6e, vimentin, PF4) and FLDM (Ccl7, Ccl2) after hypoxia. We further identified hypoxia-induced transcripts within these subsets that are regulated by the RNA-binding protein HuR. These findings define translational differences in macrophage subset gene expression programs, highlighting potential therapeutic targets in ischemic myocardium.

Clinical Impact of Multiplex Molecular Diagnostic Testing in Children with Acute Gastroenteritis Presenting to An Emergency Department: A Multicenter Prospective Study.

Background: Multiplex molecular diagnostic panels have greatly enhanced detection of gastrointestinal pathogens. However, data on the impact of these tests on clinical and patient-centered outcomes are limited. Methods: We conducted a prospective, multicenter, stepped-wedge trial to determine the impact of multiplex molecular testing at five academic children's hospitals in children presenting to the ED with acute gastroenteritis. Caregivers were interviewed on enrollment and again 7-10 days after enrollment to determine symptoms, risk factors, subsequent medical visits, and impact on family members. During the pre-intervention period, diagnostic testing was performed at the discretion of clinicians. During the intervention period, multiplex molecular testing was performed on all children with results available to clinicians. Primary outcome was return visits to a health care provider within 10 days of enrollment. Results: Potential pathogens were identified by clinician ordered tests in 19/571 (3.3%) in the pre-intervention period compared to 434/586 (74%) in the intervention period; clinically relevant pathogens were detected in 2.1% and 15% respectively. In the multivariate model adjusting for potential confounders, the intervention was associated with a 21% reduction in the odds of any return visit (OR 0.79; 95% CI 0.70-0.90). Appropriate treatment was prescribed in 11.3% compared to 19.6% during the intervention period(P=0.22). Conclusions: Routine molecular multiplex testing for all children presenting to the ED with AGE detected more clinically relevant pathogens and led to a 21% decrease in return visits. Additional research is needed to define patients most likely to benefit from testing.

Variation in Treatment of Pediatric Tuberculosis Infection in Different Provider Settings.

OBJECTIVES: To evaluate implementation of rifamycin-based regimens (RBR) for pediatric tuberculosis infection (TBI) treatment among 3 provider settings in a high-incidence county. STUDY DESIGN: A multicenter, retrospective observational study was performed across 3 sites in Los Angeles County: an academic center (AC), a general pediatrics federally qualified health center (FQHC), and department of public health (DPH) tuberculosis clinics. Patients initiated on TBI treatment age 1 months to 17 years between 2018 and 2020 were included. RBRs were defined as regimens: 3 months of weekly rifapentine and isoniazid, 4 months of daily rifampin, and 3 months of daily isoniazid and rifampin. RESULTS: We included 424 patients: 51 from AC, 327 from DPH, and 46 from FQHC. RBR use nearly doubled during the study period (from 43% in 2018 to 82% in 2020; P < .001). FQHC had the shortest time to chest radiograph and treatment initiation; however, AC and DPH were 4 times as likely to prescribe an RBR compared to FQHC (95% CI, 2.1-7.8). AC and DPH had similar completion rates (74%) and were 2.6 times as likely to complete treatment compared to FQHC (95% CI, 1.4-4.9). CONCLUSIONS: The use of RBRs for pediatric TBI varies significantly by clinical setting but is improving over time. Strategies are needed to improve RBR uptake, standardize care, and increase treatment completion, particularly among general pediatricians.

Effects of androgen excess and body mass index on endothelial function in women with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is associated with endothelial dysfunction; whether this is attributable to comorbid hyperandrogenism and/or obesity remains to be established. Therefore, we 1) compared endothelial function between lean and overweight/obese (OW/OB) women with and without androgen excess (AE)-PCOS and 2) examined androgens as potential modulators of endothelial function in these women. The flow-mediated dilation (FMD) test was applied in 14 women with AE-PCOS (lean: n = 7; OW/OB: n = 7) and 14 controls (CTRL; lean: n = 7, OW/OB: n = 7) at baseline (BSL) and following 7 days of ethinyl estradiol supplementation (EE; 30 µg/day) to assess the effect of a vasodilatory therapeutic on endothelial function; at each time point we assessed peak increases in diameter during reactive hyperemia (%FMD), shear rate, and low flow-mediated constriction (%LFMC). BSL %FMD was attenuated in lean AE-PCOS versus both lean CTRL (5.2 ± 1.5 vs. 10.3 ± 2.6%, P < 0.01) and OW/OB AE-PCOS (5.2 ± 1.5 vs. 6.6 ± 0.9%, P = 0.048). A negative correlation between BSL %FMD and free testosterone was observed in lean AE-PCOS only (R2 = 0.68, P = 0.02). EE increased %FMD in both OW/OB groups (CTRL: 7.6 ± 0.6 vs. 10.4 ± 2.5%, AE-PCOS: 6.6 ± 0.9 vs. 9.6 ± 1.7%, P < 0.01), had no impact on %FMD in lean AE-PCOS (5.17 ± 1.5 vs. 5.17 ± 1.1%, P = 0.99), and reduced %FMD in lean CTRL (10.3 ± 2.6 vs. 7.6 ± 1.2%, P = 0.03). Collectively, these data indicate that lean women with AE-PCOS exhibit more severe endothelial dysfunction than their OW/OB counterparts. Furthermore, endothelial dysfunction appears to be mediated by circulating androgens in lean but not in OW/OB AE-PCOS, suggesting a difference in the endothelial pathophysiology of AE-PCOS between these phenotypes.NEW & NOTEWORTHY We present evidence for marked endothelial dysfunction in lean women with androgen excess polycystic ovary syndrome (AE-PCOS) that is 1) associated with free testosterone levels, 2) impaired relative to overweight/obese women with AE-PCOS, and 3) unchanged following short-term ethinyl estradiol supplementation. These data indicate an important direct effect of androgens on the vascular system in women with AE-PCOS. Our data also suggest that the relationship between androgens and vascular health differs between phenotypes of AE-PCOS.

Building Resilient Agricultural Communities: A Process for Addressing Mental Health Challenges in Agricultural Communities.

The impacts of stress on physical and mental health are increasingly salient, and understanding how occupational stress interacts with occupational health and safety will shape conditions and cultures for workers. The Upper Midwest Agricultural Safety and Health Center (UMASH) recognized a need to better understand occupational stressors and mental health outcomes in agriculture, and identify barriers to mental health care along with interventions to improve this system. UMASH hosted a one-day working forum that framed agricultural stress and poor mental health, and potential for interventions, for Minnesota farmers, agricultural workers, and their families. Building Resilient Agricultural Communities engaged a spectrum of stakeholders in agricultural work including: representatives of agricultural workers, farmers, health care, policy makers, and more. The forum further defined stressors and systemic barriers to health care for agricultural workers through presentations, panel discussion, that facilitated discussions and recommendations for intervention. Priority areas to focus outreach and engagement efforts, research, and screening are shared out, with reference to the continued outcomes and impact of this forum.

Assessing the Impact of the American Heart Association's Research Portfolio: A Scientific Statement From the American Heart Association.

A task force composed of American Heart Association (AHA) Research Committee members established processes to measure the performance of the AHA's research portfolio and evaluated key outcomes that are fundamental to the overall success of the program. This report reviews progress that the AHA research program has had in achieving its goals relevant to the research programs in the AHA's research portfolio from 2008 to 2017. Comprehensive performance metrics were identified to assess the impact of AHA funding on researchers' career progress and research outcomes. Metrics included bibliometric analysis (ie, tracking of publications and their impact) and career development measures (ie, subsequent grant funding, intellectual property, faculty appointment/promotion, or industry position). Publication rates ranged from ≈0.5 to 4 publications per year, with a strong correlation between number of publications per year and later career stage. The Field-Weighted Citation Index, a metric of bibliometric impact, was between 1.5 and 3.0 for all programs, indicating that AHA awardee publications had a higher citation impact compared with similar publications. To gain insight into the career progression of AHA awardees, a 2-year postaward survey was distributed. Of the Postdoctoral Fellowship recipient respondents, 72% obtained academic research positions, with the remaining working in industry or government research settings; 72% of those in academic positions obtained additional funding. Among respondents who were Beginning Grant-in-Aid and Scientist Development Grant awardees, 45% received academic promotions and 83% obtained additional funding. Measuring performance of the AHA's research portfolio is critical to ensure that its strategic goals are met and to show the AHA's commitment to high-quality, impactful research.

Coronavirus Disease 2019 Vaccine Booster Effects Are Seen in Human Milk Antibody Response.

Infants remain at high risk for severe coronavirus disease 2019 (COVID-19). Human milk contains high levels of protective SARS CoV-2 specific antibodies post-infection and primary vaccine series, but levels decline over time. We hypothesized that the COVID-19 booster vaccine augment antibody production and the protection afforded to human milk-fed infants. We prospectively enrolled pregnant or lactating mothers planning to receive COVID-19 vaccination. We measured human milk IgG, IgA, and IgM antibodies targeting the SARS CoV-2 receptor binding domain within the spike protein and human milk neutralization activity against SARS CoV-2 in 10 lactating mothers from pre-COVID-19 primary series vaccine to post-booster dose. Human milk SARS CoV-2 specific IgG increased significantly from pre- to post-booster levels (median OD 0.33 vs. 2.02, P = 0.002). The IgG levels post-booster were even higher than the peak level after the primary series (2.02 vs. 0.95, P = 0.03). The increase in SARS CoV-2 specific IgA levels was not significant (0.10 vs. 0.33, P = 0.23). There was a strong correlation between paired maternal blood and milk IgG and IgA levels (IgG rho 0.52, P < 0.001, IgA rho 0.31, P = 0.05). Post-booster neutralizing activity was elevated compared to pre-booster levels (66% vs. 12% inhibition, P = 0.002). COVID-19 vaccine booster elicits SARS CoV-2 specific antibodies in human milk at higher levels compared to the initial primary series. This finding suggests that three doses of COVID-19 mRNA vaccination leads to improved mucosal response in human milk and reinforces current guidance recommending all pregnant or lactating mothers receive full COVID-19 vaccine courses with a booster dose.

Indole as a new tentative marker in exhaled breath for non-invasive blood glucose monitoring of diabetic subjects.

Blood glucose monitoring (BGM) is the most important part of diabetes management. In classical BGM, glucose measurement by test strips involves invasive finger pricking. We present results of a clinical study that focused on a non-invasive approach based on volatile organic compounds (VOCs) in exhaled breath. Main objective was the discovery of markers for prediction of blood glucose levels (BGLs) in diabetic patients. Exhaled breath was measured repeatedly in 60 diabetic patients (30 type 1, 30 type 2) in fasting state and after a standardized meal. Proton transfer reaction time of flight mass spectrometry was used to sample breath every 15 min for a total of 6 h. BGLs were tested in parallel via BGM test strips. VOC signals were plotted against glucose trends for each subject to identify correlations. Exhaled indole (a bacterial metabolite of tryptophan) showed significant mean correlation to BGL (with negative trend) and significant individual correlation in 36 patients. The type of diabetes did not affect this result. Additional experiments of one healthy male subject by ingestion of lactulose and13C-labeled glucose (n= 3) revealed that exhaled indole does not directly originate from food digestion by intestinal microbiota. As indole has been linked to human glucose metabolism, it might be a tentative marker in breath for non-invasive BGM. Clinical studies with greater diversity are required for confirmation of such results and further investigation of metabolic pathways.

A Longitudinal Study of Assisted Infant Toilet Training During the First Year of Life.

OBJECTIVE: Previous retrospective studies have examined elimination signals, stool toileting refusal, and completion age in Assisted Infant Toilet Training (AITT). The aim of this longitudinal cohort study was to describe the practice of AITT and caregiver satisfaction in a primarily Western setting during the first year of life. METHODS: Families who started AITT before 4 months of age were recruited. Standardized interviews of caregivers were conducted at 1- to 2-month intervals. To identify trends over time, data were fitted to a linear mixed-effect model. Data were analyzed according to five 2-month blocks, starting at 3 to 4 months. RESULTS: Of 85 participating families, 87 children started AITT at a mean age of 2.5 months. At all age intervals, 88% to 94% of caregivers could identify elimination signals. Toileting attempts decreased from 10/day at 3 to 4 months to 7/day at 11 to 12 months (p < 0.001). Many families (45%-53%) practiced AITT on a part-time basis. Daytime dryness was noted in 12% to 14% of infants throughout the first year. Although more than 63% of families used cloth or disposable diapers throughout this study, use of trainers and underwear increased significantly by 2- to 3-fold (p < 0.01 for both). Caregiver satisfaction was high overall. Although negatively associated with potty refusal, it was positively associated with daytime and nighttime dryness, perceived elimination signals, and a better understanding of their infant's needs (p < 0.001 for all). CONCLUSION: This study demonstrates that AITT is a worthy viable alternative to the use of diapers even in Western settings. Better understanding of AITT provides a new perspective to properly meet infants' basic needs.

High Prevalence of SARS-CoV-2 Genetic Variation and D614G Mutation in Pediatric Patients With COVID-19.

BACKGROUND: The full spectrum of the disease phenotype and viral genotype of coronavirus disease 2019 (COVID-19) have yet to be thoroughly explored in children. Here, we analyze the relationships between viral genetic variants and clinical characteristics in children. METHODS: Whole-genome sequencing was performed on respiratory specimens collected for all SARS-CoV-2-positive children (n = 141) between March 13 and June 16, 2020. Viral genetic variations across the SARS-CoV-2 genome were identified and investigated to evaluate genomic correlates of disease severity. RESULTS: Higher viral load was detected in symptomatic patients (P = .0007) and in children <5 years old (P = .0004). Genomic analysis revealed a mean pairwise difference of 10.8 single nucleotide variants (SNVs), and the majority (55.4%) of SNVs led to an amino acid change in the viral proteins. The D614G mutation in the spike protein was present in 99.3% of the isolates. The calculated viral mutational rate of 22.2 substitutions/year contrasts the 13.5 substitutions/year observed in California isolates without the D614G mutation. Phylogenetic clade 20C was associated with severe cases of COVID-19 (odds ratio, 6.95; P = .0467). Epidemiological investigation revealed major representation of 3 of 5 major Nextstrain clades (20A, 20B, and 20C) consistent with multiple introductions of SARS-CoV-2 in Southern California. CONCLUSIONS: Genomic evaluation demonstrated greater than expected genetic diversity, presence of the D614G mutation, increased mutation rate, and evidence of multiple introductions of SARS-CoV-2 into Southern California. Our findings suggest a possible association of phylogenetic clade 20C with severe disease, but small sample size precludes a definitive conclusion. Our study warrants larger and multi-institutional genomic evaluation and has implications for infection control practices.

Early exposure to antibiotics in the neonatal intensive care unit alters the taxonomic and functional infant gut microbiome.

INTRODUCTION: The infant gut microbiome is thought to play a key role in developing metabolic and immunologic pathways. Antibiotics have been shown to disrupt the human microbiome, but the impact they have on infants during this key window of development remains poorly understood. Through this study, we further characterize the effect antibiotics have on the gut microbiome of infants by looking at metagenomic sequencing data over time. MATERIALS AND METHODS: Stool samples were collected on infants from a large tertiary care neonatal intensive care unit. After DNA extraction, metagenomics libraries were generated and sequenced. Taxonomic and functional analyses were then performed. Further directed specimen sequencing for fungal species was also performed. RESULTS: A total of 51 stool samples from 25 infants were analyzed: seven infants were on antibiotics during at least one of their collection time points. Antibiotics given at birth altered the microbiome (PERMANOVA R2 = 0.044, p = .002) but later courses did not (R2 = 0.023, p = .114). Longitudinal samples collected while off antibiotics were more similar than those collected during a transition on or off antibiotics (mean Bray-Curtis distance 0.29 vs. 0.63, Wilcoxon p = .06). Functional analysis revealed four microbial pathways that were disrupted by antibiotics given at-birth (p < .1, folate synthesis, glycerolipid metabolism, fatty acid biosynthesis, and glycolysis). No functional changes associated with current antibiotic use were identified. In a limited sample set, we saw little evidence of fungal involvement in the overall infant microbiome. CONCLUSION: Through this study, we have further characterized the role antibiotics have in the development of the infant microbiome. Antibiotics given at birth were associated with alterations in the microbiome and had significant impact on the functional pathways involved in folate synthesis and multiple metabolic pathways. Later courses of antibiotics led to stochastic dysbiosis and a significant decrease in Escherichia coli. Further characterization of the infant mycobiome is still needed.