The human gastrointestinal tract (GIT) represents one of the most densely populated microbial ecosystems studied to date. Although this microbial consortium has been recognized to have a crucial ...impact on human health, its precise composition is still subject to intense investigation. Among the GIT microbiota, bifidobacteria represent an important commensal group, being among the first microbial colonizers of the gut. However, the prevalence and diversity of members of the genus Bifidobacterium in the infant intestinal microbiota has not yet been fully characterized, while some inconsistencies exist in literature regarding the abundance of this genus.
In the current report, we assessed the complexity of the infant intestinal bifidobacterial population by analysis of pyrosequencing data of PCR amplicons derived from two hypervariable regions of the 16 S rRNA gene. Eleven faecal samples were collected from healthy infants of different geographical origins (Italy, Spain or Ireland), feeding type (breast milk or formula) and mode of delivery (vaginal or caesarean delivery), while in four cases, faecal samples of corresponding mothers were also analyzed.
In contrast to several previously published culture-independent studies, our analysis revealed a predominance of bifidobacteria in the infant gut as well as a profile of co-occurrence of bifidobacterial species in the infant's intestine.
Coronaviruses are known to precipitate disorders of smell and taste function. With the emerging global coronavirus disease (CoVID19) pandemic due to the severe acute respiratory syndrome coronavirus ...2, early reports suggested that smell and taste dysfunction were clinical features of CoVID19. Our study aimed to investigate the prevalence of smell and taste disturbances in a cohort of CoVID19 positive patients who were isolated at home and being medically managed through telephone consultation.
This was a retrospective cross-sectional study conducted at St. James’s Hospital Dublin, an urban 850 bed tertiary referral centre. 46 out of 50 CoVID19 positive patients, managed through a telephone clinic from the hospital infectious disease department, were assessed for olfactory and gustatory function loss.
The median age of participants was 36.5 years (interquartile range (IQR) 27 - 48) and 19 (41%) were male. The majority (31; 67%) never smoked and 17 (37%) reported co-morbidities. Approximately half of patients reported some degree of smell (22; 48%) or taste (25; 54%) function loss. 13 patients (28%) reported a complete loss of sense of smell, 8 (17%) reported a complete loss of sense of taste and 7 (15%) reported simultaneous total loss of both. The median age of patients with any degree of smell disturbance was significantly lower than patients without (median 30.5 years (IQR 24 – 43.25) versus 41 years (IQR 28.25 – 52.75), p = 0.025). The median age of patients with any degree of taste disturbance was lower than those without, but did not reach statistical significance (median 34 years (IQR 24 - 45) versus 40 years (IQR 27.5 – 52.5) p = 0.174).
Smell or taste dysfunction were present in our defined subgroup of patients. Further research is required in different population cohorts to build the evidence base for smell and taste dysfunction as clinical indicators of CoVID19 disease and to assess if these symptoms persist after disease resolution.
Serological assays have been widely employed during the coronavirus disease 2019 (COVID-19) pandemic to measure antibody responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and ...to track seroconversion in populations. However, currently available assays do not allow determination of neutralization capacity within the assay protocol. Furthermore, commercial serology assays have a high buy-in cost that is inaccessible for many research groups. We have replicated the serological enzyme-linked immunosorbent assay for the detection of SARS-CoV-2 antibody isotypes, developed at the Icahn School of Medicine at Mount Sinai, New York. Additionally, we have modified the protocol to include a neutralization assay with only a minor modification to this protocol. We used this assay to screen local COVID-19 patient sera (n = 91) and pre-COVID-19 control sera (n = 103), and obtained approximate parity with approved commercial anti-nucleoprotein-based assays with these sera. Furthermore, data from our neutralization assay closely aligns with that generated using a spike-based pseudovirus infection model when a subset of patient sera was analyzed.
In October 2020 SARS-CoV-2 seroprevalence among hospital healthcare workers (HCW) of two Irish hospitals was 15 and 4. 1%, respectively. We compare seroprevalence in the same HCW population 6 months ...later, assess changes in risk factors for seropositivity with progression of the pandemic and serological response to vaccination.
All staff of both hospitals (
= 9,038) were invited to participate in an online questionnaire and SARS-CoV-2 antibody testing in April 2021. We measured anti-nucleocapsid and anti-spike antibodies. Frequencies and percentages for positive SARS-CoV-2 antibodies were calculated and adjusted relative risks for participant characteristics were calculated using multivariable regression analysis.
Five thousand and eighty-five HCW participated. Seroprevalence increased to 21 and 13%, respectively; 26% of infections were previously undiagnosed. Black ethnicity (aRR 1.7, 95% CI 1.3-2.2,
< 0.001), lower level of education (aRR 1.4 for secondary level education, 95% CI 1.1-1.8,
= 0.002), living with other HCW (aRR 1.2, 95% CI 1.0-1.4,
= 0.007) were significantly associated with seropositivity. Having direct patient contact also carried a significant risk being a healthcare assistant (aRR 1.8, 95% CI 1.3-2.3,
< 0.001), being a nurse (aRR 1.4, 95% CI 1.0-1.8,
= 0.022), daily contact with COVID-19 patients (aRR 1.4, 95% CI 1.1-1.7,
= 0.002), daily contact with patients without suspected or confirmed COVID-19 (aRR 1.3, 95% CI 1.1-1.5,
= 0.013). Breakthrough infection occurred in 23/4,111(0.6%) of fully vaccinated participants; all had anti-S antibodies.
The increase in seroprevalence reflects the magnitude of the third wave of the pandemic in Ireland. Genomic sequencing is needed to apportion risk to the workplace vs. the household/community. Concerted efforts are needed to mitigate risk factors due to ethnicity and lower level of education, even at this stage of the pandemic. The undiagnosed and breakthrough infections call for ongoing infection prevention and control measures and testing of HCW in the setting of close contact. Vaccinated HCW with confirmed infection should be actively assessed, including SARS-CoV-2 whole genome sequencing (WGS), serology testing and assessment of host determinants, to advance understanding of the reasons for breakthrough infection.
IntroductionHealth systems worldwide have had to prepare for a surge in volume in both the outpatient and inpatient settings since the emergence of COVID-19. Early international healthcare ...experiences showed approximately 80% of patients with COVID-19 had mild disease and therfore could be managed as outpatients. However, SARS-CoV-2 can cause a biphasic illness with those affected experiencing a clinical deterioration usually seen after day 4 of illness.ObjectiveWe created an online tool with the primary objective of allowing for virtual disease triage among the increasing number of outpatients diagnosed with COVID-19 at our hospital. Secondary aims included COVID-19 education and the promotion of official COVID-19 information among these outpatients, and analysis of reported symptomatology.MethodsOutpatients with acute COVID-19 disease received text messages from the hospital containing a link to an online symptom check-in tool which they were invited to complete.Results296 unique participants (72%) from 413 contacted by text completed the online check-in tool at least once, generating 831 responses from 1324 texts sent. 83% of text recipients and 91% of unique participants were healthcare workers. 7% of responses to the tool were from participants who admitted to a slight worsening of their symptoms during follow-up. Fatigue was the most commonly reported symptom overall (79%), followed by headache (72%). Fatigue, headache and myalgia were the most frequently reported symptoms in the first 3 days of illness. 8% of responses generated in the first 7 days of illness did not report any of the cardinal symptoms (fever, cough, dyspnoea, taste/smell disturbance) of COVID-19. Participants found the tool to be useful and easy to use, describing it as ‘helpful’ and ‘reassuring’ in a follow-up feedback survey (n=140). 93% said they would use such a tool in the future. 39% reported ongoing fatigue, 16% reported ongoing smell disturbance and 14% reported ongoing dyspnoea after 6 months.ConclusionThe online symptom check-in tool was found to be acceptable to participants and saw high levels of engagement and satisfaction. Symptomatology findings highlight the variety and persistence of symptoms experienced by those with confirmed COVID-19 disease
To examine the composition of the evolving microbiota of preterm infants at weeks 2 and 4 of life.
The paediatric intensive care unit of the Cork University Maternity Hospital.
The microbial ...diversity of faecal samples from 10 preterm infants was determined using 16S rRNA amplicon pyrosequencing technology.
In total, 452 863 sequences were obtained from 20 faecal samples collected from 10 preterm infants, allowing a level of analysis not previously reported. The preterm infant microbiota samples were dominated by Proteobacteria (46%), followed by Firmicutes (45%), while the phyla Actinobacteria (2%) and Bacteroidetes (7%) were detected at much lower levels at week 2 of life. This colonisation pattern was similar at week 4 of life. At the family level, Enterobacteriaceae were detected at 50% and 58% at weeks 2 and 4, respectively. The preterm infants were characterised by a lack of detectable Bifidobacterium and Lactobacillus genera commonly associated with the infant gut. In addition to the dominance of the Proteobacteria, a high level of interindividual variation was observed, indeed the relative proportions of different phyla, families and genera in different infants ranged from <1% to >90%.
The results indicate that in addition to an uncharacteristic microbiota relative to that reported for healthy term infants, there was a large interindividual variation in the faecal microbiota diversity of preterm infants suggesting that the preterm microbiota is individual-specific and does not display a uniformity among infants.
Introduction
Serological SARS-CoV-2 assays have an important role in guiding the pandemic response. This research aimed to compare the performance of 2 antinucleocapsid assays.
Methods
Serum from 49 ...HCWs was analysed at baseline and 6 months using the Abbott diagnostics SARS-CoV-2 IgG assay and the Roche Diagnostics Elecsys Anti-SARS-CoV-2 total antibody assay.
Results
At baseline, 14/49 participants (29%) demonstrated antibody reactivity using the Abbott assay. At 6 months, 4/14 participants (29%) continued to demonstrate reactivity. A total of 14/49 (29%) participants had detectable antibodies at baseline using the Roche assay. In total, 13/14 (93%) of participants demonstrated antibody reactivity at 6 months. The Abbott assay showed a statistically significant difference in the signal-to-threshold values of baseline reactive samples when repeated at 6 months (p = 0.001). This was not seen with the Roche assay (p = 0.51).
Conclusion
In this small study, the Roche Diagnostics Elecsys Anti-SARS-CoV-2 total antibody assay appears superior in performance to the Abbott diagnostics SARS-CoV-2 IgG assay in accurately detecting participants with a history of confirmed COVID-19 disease at 6 months follow-up. This finding should be born in mind in the planning of future seroprevalence studies, especially when considering the use of anti-nucleocapsid assays.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies are an excellent indicator of past COVID-19 infection. As the COVID-19 pandemic progresses, retained sensitivity over time is ...an important quality in an antibody assay that is to be used for the purpose of population seroprevalence studies. We compared 5,788 health care worker (HCW) serum samples by using two serological assays (Abbott SARS-CoV-2 anti-nucleocapsid immunoglobulin G (IgG) and Roche anti-SARS-CoV-2 anti-nucleocapsid total antibody) and a subset of samples (all Abbott assay positive or grayzone,
= 485) on Wantai SARS-CoV-2 anti-spike antibody enzyme-linked immunosorbent assay (ELISA). For 367 samples from HCW with a previous PCR-confirmed SARS-CoV-2 infection, we correlated the timing of infection with assay results. Overall, seroprevalence was 4.2% on Abbott and 9.5% on Roche. Of those with previously confirmed infection, 41% (150/367) and 95% (348/367) tested positive on Abbott and Roche, respectively. At 21 weeks (150 days) after confirmed infection, positivity on Abbott started to decline. Roche positivity was retained for the entire study period (33 weeks). Factors associated (
≤ 0.050) with Abbott seronegativity in those with previous PCR-confirmed infection included sex (odds ratio OR, 0.30 male ; 95% confidence interval CI, 0.15 to 0.60), symptom severity (OR 0.19 severe symptoms; 95% CI, 0.05 to 0.61), ethnicity (OR, 0.28 Asian ethnicity; 95% CI, 0.12 to 0.60), and time since PCR diagnosis (OR, 2.06 for infection 6 months previously; 95% CI, 1.01 to 4.30). Wantai detected all previously confirmed infections. In our population, Roche detected antibodies up to at least 7 months after natural infection with SARS-CoV-2. This finding indicates that the Roche total antibody assay is better suited than Abbott IgG assay to population-based studies. Wantai demonstrated high sensitivity, but sample selection was biased. The relationship between serological response and functional immunity to SARS-CoV-2 infection needs to be delineated.
As the COVID-19 pandemic progresses, retained sensitivity over time is an important quality in an antibody assay that is to be used for the purpose of population seroprevalence studies. There is a relative paucity of published literature in this field to help guide public health specialists when planning seroprevalence studies. In this study, we compared results of 5,788 health care worker blood samples tested by using two assays (Roche and Elecsys, anti-nucleocapsid antibody) and by testing a subset on a third assay (Wantai enzyme-linked immunosorbent assay ELISA anti-spike antibody). We found significant differences in the performance of these assays, especially with distance in time from PCR-confirmed COVID-19 infection, and we feel these results may significantly impact the choice of assay for others conducting similar studies.
Recently published observational data suggests an increased risk of herpes zoster infection post-vaccination with the BNT162b2 mRNA vaccine. We describe the case of VZV meningitis post BNT162b2 mRNA ...vaccination in a young immunocompetent patient. A 39-year-old patient with no medical history presented with a vesicular rash, headache, nausea and fever, days after receiving BNT162b2 mRNA vaccination. CSF analysis revealed a pleocytosis, and VZV DNA was confirmed by PCR testing. The patient received intravenous aciclovir with resolution of symptoms within 48 h. He was discharged after 14 days of treatment. Case reports of herpes zoster reactivation post vaccination and details of subsequent successful vaccination course completion have allowed us to recommend the patient receive his second dose of the BNT162b2 mRNA vaccine. At the time of writing, however, the patient has declined to receive further vaccination due to fears of an adverse event. To the best of our knowledge, this is the first reported case in a young patient of herpes zoster meningitis following COVID-19 mRNA vaccination. The sharing of clinical experiences and reporting of suspected side effects, particularly for vaccines that employ novel technology, increases knowledge of the safety profile of these vaccines and allows clinicians to better aid patients make informed decisions with regard to commencing and completing vaccination.
In the present study we demonstrate that the initial attachment of Listeria monocytogenes cells to plastic surfaces was significantly increased by growth in the presence of bile. Improved biofilm ...formation was confirmed by crystal violet staining, microscopy and bioluminescence detection of a luciferase-tagged strain. Enhanced biofilm formation in response to bile may influence the ability of L. monocytogenes to form biofilms in vivo during infection and may contribute to survival of this important pathogen in the human gastrointestinal tract and gallbladder.
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