SARS-CoV-2 Vaccine Breakthrough Infections of Omicron and Delta Variants in Healthcare Workers.

Understanding SARS-CoV-2 breakthrough infections in vaccinated healthcare workers is of key importance in mitigating the effects of the COVID-19 pandemic in healthcare facilities. An observational prospective cohort study was conducted in vaccinated employees with acute SARS-CoV-2 infection between October 2021 and February 2022. Serological and molecular testing was performed to determine SARS-CoV-2 viral load, lineage, antibody levels, and neutralizing antibody titers. A total of 571 (9.7%) employees experienced SARS-CoV-2 breakthrough infections during the enrolment period, of which 81 were included. The majority (n = 79, 97.5%) were symptomatic and most (n = 75, 92.6%) showed Ct values < 30 in RT-PCR assays. Twenty-four (30%) remained PCR-positive for > 15 days. Neutralizing antibody titers were strongest for the wildtype, intermediate for Delta, and lowest for Omicron variants. Omicron infections occurred at higher anti-RBD-IgG serum levels (p = 0.00001) and showed a trend for higher viral loads (p = 0.14, median Ct difference 4.3, 95% CI [-2.5-10.5]). For both variants, viral loads were significantly higher in participants with lower anti-RBD-IgG serum levels (p = 0.02). In conclusion, while the clinical course of infection with both the Omicron and Delta variants was predominantly mild to moderate in our study population, waning immune response over time and prolonged viral shedding were observed.

Chylothorax due to hepatic alveolar echinococcosis with infiltration of diaphragm and left pleura: a case report.

BACKGROUND: Alveolar echinococcosis (AE) is an endemic parasitic zoonosis in Germany. In most cases, the liver is the primary organ affected. CASE PRESENTATION: A 59-year old female patient presented with increasing exertional dyspnea and unintentional weight loss. A computed tomography (CT) scan showed a left-sided chylous pleural effusion and multiple intrahepatic masses with infiltration of the diaphragm and the pleura. The findings were initially misinterpreted as hepatocellular carcinoma (HCC) with infiltrating growth. Liver biopsy of one of the masses showed no evidence of malignancy, but an amorphous necrosis of unclear origin. HCC was further ruled out by magnetic resonance imaging (MRI). However, MRI findings were highly suspicious for hepatothoracic dissemination and complications due to AE. Typical histologic findings in a repeated and more specific examination of the liver tissue and a positive serology for echinococcosis confirmed the diagnosis of AE. As the hepatic and pulmonary manifestations were considered inoperable in a curative matter, an anti-parasitic treatment with albendazole was initiated. A video-assisted thoracoscopic surgery (VATS) with removal of the chylous effusion as well as a talc pleurodesis was performed to relieve the patient from dyspnea. Two months later, the patient was asymptomatic and a positron emission tomography (PET)-CT-scan with [18 F] fluoro-2-deoxy-d-glucose (FDG) showed a remarkable diminution of the hepatic manifestation. CONCLUSIONS: This case demonstrates a rare presentation of alveolar echinococcosis with a focus on pulmonary symptoms, emphasizing the importance of evaluation for pulmonary involvement in patients with AE and respiratory symptoms.

Clinical outcomes of hospitalized COVID-19 patients treated with remdesivir: a retrospective analysis of a large tertiary care center in Germany.

PURPOSE: The benefits of antiviral treatment with remdesivir in hospitalized patients with COVID-19 remain controversial. Clinical analyses are needed to demonstrate which patient populations are most likely to benefit. METHODS: In a retrospective monocentric analysis, patients with COVID-19 treated between July 1, 2020 and June 30, 2021 at Hospital St. Georg, Leipzig, Germany were evaluated. The primary endpoint was time to clinical improvement, and the secondary endpoint was 28-day mortality. Propensity score matching was used for the endpoint analysis. RESULTS: A total of 839 patients were fully evaluated, 68% of whom received specific COVID-19 drug therapy. Remdesivir was used in 31.3% of the patients, corticosteroids in 61.7%, and monoclonal antibodies in 2.3%. While dexamethasone administration was the most common therapeutic approach during the second pandemic wave, combination therapy with remdesivir and corticosteroids predominated during the third wave. Cox regression analysis revealed that combination therapy was not associated with faster clinical improvement (median: 13 days in both matched groups, HR 0.97 [95% CI 0.77-1.21], P = 0.762). By contrast, 28-day mortality was significantly lower in the corticosteroid-remdesivir group (14.8% versus 22.2% in the corticosteroid group, HR 0.60 [95% CI 0.39-0.95], P = 0.03) in the low-care setting. This effect was also demonstrated in a subgroup analysis of patients with remdesivir monotherapy (n = 44) versus standard of care (SOC). CONCLUSION: In COVID-19 patients with only mild disease (low-flow oxygen therapy and treatment in a normal ward) who received corticosteroids and/or remdesivir in addition to SOC, early administration of remdesivir was associated with a measurable survival benefit.

Evaluation of the systemic and mucosal immune response induced by COVID-19 and the BNT162b2 mRNA vaccine for SARS-CoV-2.

BACKGROUND: The currently used SARS-CoV-2 mRNA vaccines have proven to induce a strong and protective immune response. However, functional relevance of vaccine-generated antibodies and their temporal progression are still poorly understood. Thus, the central aim of this study is to gain a better understanding of systemic and mucosal humoral immune response after mRNA vaccination with BNT162b2. METHODS: We compared antibody production against the S1 subunit and the RBD of the SARS-CoV-2 spike protein in sera of BNT162b2 vaccinees, heterologous ChAdOx1-S/BNT162b2 vaccinees and COVID-19 patients. We monitored the neutralizing humoral response against SARS-CoV-2 wildtype strain and three VOCs over a period of up to eight months after second and after a subsequent third vaccination. RESULTS: In comparison to COVID-19 patients, vaccinees showed higher or similar amounts of S1- and RBD-binding antibodies but similar or lower virus neutralizing titers. Antibodies peaked two weeks after the second dose, followed by a decrease three and eight months later. Neutralizing antibodies (nAbs) poorly correlated with S1-IgG levels but strongly with RBD-IgGAM titers. After second vaccination we observed a reduced vaccine-induced neutralizing capacity against VOCs, especially against the Omicron variant. Compared to the nAb levels after the second vaccination, the neutralizing capacity against wildtype strain and VOCs was significantly enhanced after third vaccination. In saliva samples, relevant levels of RBD antibodies were detected in convalescent samples but not in vaccinees. CONCLUSIONS: Our data demonstrate that BNT162b2 vaccinated individuals generate relevant nAbs titers, which begin to decrease within three months after immunization and show lower neutralizing potential against VOCs as compared to the wildtype strain. Large proportion of vaccine-induced S1-IgG might be non-neutralizing whereas RBD-IgGAM appears to be a good surrogate marker to estimate nAb levels. A third vaccination increases the nAb response. Furthermore, the systemic vaccine does not seem to elicit readily detectable mucosal immunity.

Comparison of the certified Copan eSwab system with commercially available cotton swabs for the detection of multidrug-resistant bacteria in rectal swabs.

BACKGROUND: Rectal swabs are well-implemented screening tools for multidrug-resistant bacteria (MDRB). Since certified swabs such as the Copan eSwab system experienced a delivery bottleneck during the COVID-19 pandemic, commercially available alternatives such as commonly used double-tipped cotton swabs had to be investigated, especially considering their similarity to professional cotton swabs for microbiological purposes. METHODS: Diagnostic properties of commercial cotton swabs (comparable to Q-tips) and Copan eSwabs were qualitatively compared in a prospective single-center study using microbiological standard cultures and PCR methods for the detection of multidrug-resistant Gram-negative bacteria and vancomycin-resistant enterococci (VRE). RESULTS: A total of 196 swab pairs were collected from 164 participants. MDRB were detected in 36 of 164 cases (22%). There were neither false-negative nor false-positive results using commercial cotton swabs. In 8 of 196 samples (4.1%) MDRB species were detected only by using cotton swabs, including vancomycin-resistant Enterococcus faecium, OXA-48 producing Escherichia coli, ESBL-producing Klebsiella pneumoniae and ESBL-producing Escherichia coli. DISCUSSION: Commercial cotton swabs turned out to be a reliable alternative to Copan eSwabs. For practical use as a screening tool, relevant storage- and manufacturer-related contamination must be ruled out beforehand. CONCLUSIONS: Commonly available double-tipped cotton swabs can be used for rectal MDRB screening in the event of supply shortages of certified swabs. Further studies should clarify their suitability as a sampling system for nasopharyngeal MRSA carriage or even for the molecular biological detection of SARS-CoV-2.

Predictive performance and clinical application of COV50, a urinary proteomic biomarker in early COVID-19 infection: a prospective multicentre cohort study.

BACKGROUND: The SARS-CoV-2 pandemic is a worldwide challenge. The CRIT-CoV-U pilot study generated a urinary proteomic biomarker consisting of 50 peptides (COV50), which predicted death and disease progression from SARS-CoV-2. After the interim analysis presented for the German Government, here, we aimed to analyse the full dataset to consolidate the findings and propose potential clinical applications of this biomarker. METHODS: CRIT-CoV-U was a prospective multicentre cohort study. In eight European countries (Austria, France, Germany, Greece, North Macedonia, Poland, Spain, and Sweden), 1012 adults with PCR-confirmed COVID-19 were followed up for death and progression along the 8-point WHO scale. Capillary electrophoresis coupled with mass spectrometry was used for urinary proteomic profiling. Statistical methods included logistic regression and receiver operating characteristic curve analysis with a comparison of the area under curve (AUC) between nested models. Hospitalisation costs were derived from the care facility corresponding with the Markov chain probability of reaching WHO scores ranging from 3 to 8 and flat-rate hospitalisation costs adjusted for the gross per capita domestic product of each country. FINDINGS: From June 30 to Nov 19, 2020, 228 participants were recruited, and from April 30, 2020, to April 14, 2021, 784 participants were recruited, resulting in a total of 1012 participants. The entry WHO scores were 1-3 in 445 (44%) participants, 4-5 in 529 (52%) participants, and 6 in 38 (4%) participants; and of all participants, 119 died and 271 had disease progression. The odds ratio (OR) associated with COV50 in all 1012 participants for death was 2·44 (95% CI 2·05-2·92) unadjusted and 1·67 (1·34-2·07) when adjusted for sex, age, BMI, comorbidities, and baseline WHO score; and for disease progression, the OR was 1·79 (1·60-2·01) when unadjusted and 1·63 (1·41-1·91) when adjusted (p<0·0001 for all). The predictive accuracy of the optimised COV50 thresholds was 74·4% (71·6-77·1%) for mortality (threshold 0·47) and 67·4% (64·4-70·3%) for disease progression (threshold 0·04). When adjusted for covariables and the baseline WHO score, these thresholds improved AUCs from 0·835 to 0·853 (p=0·033) for death and from 0·697 to 0·730 (p=0·0008) for progression. Of 196 participants who received ambulatory care, 194 (99%) did not reach the 0·04 threshold. The cost reductions associated with 1 day less hospitalisation per 1000 participants were million Euro (M€) 0·887 (5-95% percentile interval 0·730-1·039) in participants at a low risk (COV50 <0·04) and M€2·098 (1·839-2·365) in participants at a high risk (COV50 ≥0·04). INTERPRETATION: The urinary proteomic COV50 marker might be predictive of adverse COVID-19 outcomes. Even in people with mild-to-moderate PCR-confirmed infections (WHO scores 1-4), the 0·04 COV50 threshold justifies earlier drug treatment, thereby potentially reducing the number of days in hospital and associated costs. FUNDING: German Federal Ministry of Health.

Fever in the Returning Traveler.

BACKGROUND: It is predicted that approximately two billion tourist trips to foreign countries will be taken worldwide each year by 2030. Germany has long been among the most active countries in tourism. The frequency of illness among persons returning from developing and newly industrialized countries is 43-79%. The appropriate diagnosis of fever in returning travelers is a clinically important matter, as it can be a sign of a life-threatening illness. METHODS: This review is based on publications (2001-2022) retrieved by a selective search in PubMed for studies on the epidemiology, diagnosis, and treatment of febrile illnesses in returning travelers, or on specific tropical diseases. RESULTS: Diarrhea, fever, and skin changes are the most common manifestations of disease after travel to tropical and sub - tropical areas. The diagnostic evaluation should be performed in a series of steps, beginning with a precise travel history and the identification of specific risk factors. Among travelers returning from sub-Saharan Africa, Plasmodium falciparum malaria is the most common cause of fever on presentation to centers for infectious diseases and tropical medicine, affecting approximately 50 per 1000 travelers. Among persons returning from travel to Southeast Asia, dengue fever is the most common infectious disease, affecting 50-160 per 1000 travelers. Further potentially dangerous diseases include chikungunya and zika fever, typhoid and paratyphoid fever, amoebic liver abscess, visceral leishmaniasis (kala-azar), leptospirosis, and, very rarely, imported cases of viral hemorrhagic fever. COVID-19 and influenza are important differential diagnoses. CONCLUSION: The differential diagnosis can be narrowed by thorough history-taking with particular attention to the patient's travel route, combined with a good knowledge of the geographic spread and incubation times of the main tropical diseases. Algorithms help clinicians to focus the diagnostic work-up and select the appropriate further laboratory tests and diagnostic procedures.

[Vaccinations]. / Impfungen.

Vaccination is considered one of the most important achievements of modern medicine and has saved millions of lives. As a result, the age-old fear of severe or fatal infectious diseases has largely been forgotten in society; however, the pandemic triggered by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shows how quickly this fear can return. Also, many people have reservations about medical measures, especially if they are directed against vague dangers. Paradoxically, the success of vaccinations jeopardizes the acceptance. To counteract this development, this article provides information on basic vaccination principles, legal frameworks and components of vaccines. It explains the most important categories, goals, core elements of vaccination programs and the most important recommendations of the Standing Committee on Vaccination at the Robert Koch Institute (STIKO). It explains the current state of knowledge with respect to required resources, assessment of vaccine reactions, complication management and possible vaccine damage.

Clinical Relevance of Elevated Soluble ST2, HSP27 and 20S Proteasome at Hospital Admission in Patients with COVID-19.

Although, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) represents one of the biggest challenges in the world today, the exact immunopathogenic mechanism that leads to severe or critical Coronavirus Disease 2019 (COVID-19) has remained incompletely understood. Several studies have indicated that high systemic plasma levels of inflammatory cytokines result in the so-called "cytokine storm", with subsequent development of microthrombosis, disseminated intravascular coagulation, and multiorgan-failure. Therefore, we reasoned those elevated inflammatory molecules might act as prognostic factors. Here, we analyzed 245 serum samples of patients with COVID-19, collected at hospital admission. We assessed the levels of heat shock protein 27 (HSP27), soluble suppressor of tumorigenicity-2 (sST2) and 20S proteasome at hospital admission and explored their associations with overall-, 30-, 60-, 90-day- and in-hospital mortality. Moreover, we investigated their association with the risk of ventilation. We demonstrated that increased serum sST2 was uni- and multivariably associated with all endpoints. Furthermore, we also identified 20S proteasome as independent prognostic factor for in-hospital mortality (sST2, AUC = 0.73; HSP27, AUC = 0.59; 20S proteasome = 0.67). Elevated sST2, HSP27, and 20S proteasome levels at hospital admission were univariably associated with higher risk of invasive ventilation (OR = 1.8; p < 0.001; OR = 1.1; p = 0.04; OR = 1.03, p = 0.03, respectively). These findings could help to identify high-risk patients early in the course of COVID-19.

Impfungen Vaccinations

Impfungen gelten als eine der wichtigsten Errungenschaften der modernen Medizin und haben Millionen Menschenleben gerettet. Im Zuge dessen ist die Angst vor schweren Infektionskrankheiten in unserer Gesellschaft weitgehend in Vergessenheit geraten. Die SARS-CoV-2-Pandemie zeigt jedoch, wie schnell dieses Angstgefühl zurückkehren kann. Gleichzeitig hegen viele Menschen Vorbehalte gegenüber medizinischen Maßnahmen, insbesondere wenn sich diese gegen mehr oder weniger abstrakte Gefahren richten. Paradoxerweise gefährdet der Erfolg von Impfungen somit deren Akzeptanz. Um dem entgegenzuwirken, informiert dieser Beitrag über Impfprinzipien, rechtliche Rahmenbedingungen und Impfkomponenten. Er erklärt die wichtigsten Impfstoffkategorien, Ziele und Kernelemente von Impfprogrammen sowie die grundlegenden Empfehlungen der Ständigen Impfkommission und erläutert den Wissensstand zu erforderlichen Ressourcen, Einschätzung von Impfreaktionen, Komplikationsmanagement und möglichen Impfschäden.

Bacterial contamination of the smartphones of healthcare workers in a German tertiary-care hospital before and during the COVID-19 pandemic.

BACKGROUND: Assuming that hygiene measures have improved significantly due to COVID-19, we aimed to investigate bacterial colonization on smartphones (SPs) owned by healthcare workers (HCWs) before and during the pandemic. METHODS: Employing a before-and-after study design, randomly selected HCWs were included. Devices underwent sampling under real-life conditions, without prior manipulation. Swabs were collected in 2012 (pre-pandemic) and 2021 to determine microbial colonization. Isolates were identified by MALDI-TOF mass spectrometry and underwent microbiological susceptibility testing. RESULTS: The final analysis included 295 HCWs (67% female, mean age 34 years) from 26 wards. Bacterial contamination was present on 293 of 295 SP screens (99.3%). The proportion of clinically relevant bacterial pathogens (eg Staphylococcus aureus, enterococci, Enterobacterales, non-fermenting bacteria) ranged from 21.2% in 2012 to 39.8% in 2021. Resistance profiles revealed a proportion of multidrug-resistant bacteria such as MRSA and VRE of less than 2%. The comparison of before-and-after sampling showed a significant increase in smartphone use during work from 2012 to 2021 with a simultaneous increase in cleaning intensity, probably as a result of the COVID-19 pandemic. CONCLUSIONS: Bacterial contamination of SPs within the hospital is of concern and can serve as a source of cross-contamination. Hence, in addition to excellent hand hygiene, SPs must be carefully disinfected after handling in healthcare. Behavioral changes related to the COVID-19 pandemic could have a significant impact if implemented sustainably in everyday clinical practice.

Comprehensive investigation of an in-hospital transmission cluster of a symptomatic SARS-CoV-2-positive physician among patients and healthcare workers in Germany.

We investigated potential transmissions of a symptomatic SARS-CoV-2-positive physician in a tertiary-care hospital who worked for 15 cumulative hours without wearing a face mask. No in-hospital transmissions occurred, despite 254 contacts among patients and healthcare workers. In conclusion, exposed hospital staff continued work, accompanied by close clinical and virologic monitoring.

CD99 and polymeric immunoglobulin receptor peptides deregulation in critical COVID-19: A potential link to molecular pathophysiology?

Identification of significant changes in urinary peptides may enable improved understanding of molecular disease mechanisms. We aimed towards identifying urinary peptides associated with critical course of COVID-19 to yield hypotheses on molecular pathophysiological mechanisms in disease development. In this multicentre prospective study urine samples of PCR-confirmed COVID-19 patients were collected in different centres across Europe. The urinary peptidome of 53 patients at WHO stages 6-8 and 66 at WHO stages 1-3 COVID-19 disease was analysed using capillary electrophoresis coupled to mass spectrometry. 593 peptides were identified significantly affected by disease severity. These peptides were compared with changes associated with kidney disease or heart failure. Similarities with kidney disease were observed, indicating comparable molecular mechanisms. In contrast, convincing similarity to heart failure could not be detected. The data for the first time showed deregulation of CD99 and polymeric immunoglobulin receptor peptides and of known peptides associated with kidney disease, including collagen and alpha-1-antitrypsin. Peptidomic findings were in line with the pathophysiology of COVID-19. The clinical corollary is that COVID-19 induces specific inflammation of numerous tissues including endothelial lining. Restoring these changes, especially in CD99, PIGR and alpha-1-antitripsin, may represent a valid and effective therapeutic approach in COVID-19, targeting improvement of endothelial integrity.

Correction: Covid-19 in outpatients-Is fever a useful indicator for SARS-CoV-2 infection?

[This corrects the article DOI: 10.1371/journal.pone.0246312.].

A urinary peptidomic profile predicts outcome in SARS-CoV-2-infected patients.

BACKGROUND: COVID-19 prediction models based on clinical characteristics, routine biochemistry and imaging, have been developed, but little is known on proteomic markers reflecting the molecular pathophysiology of disease progression. METHODS: The multicentre (six European study sites) Prospective Validation of a Proteomic Urine Test for Early and Accurate Prognosis of Critical Course Complications in Patients with SARS-CoV-2 Infection Study (Crit-COV-U) is recruiting consecutive patients (≥ 18 years) with PCR-confirmed SARS-CoV-2 infection. A urinary proteomic biomarker (COV50) developed by capillary-electrophoresis-mass spectrometry (CE-MS) technology, comprising 50 sequenced peptides and identifying the parental proteins, was evaluated in 228 patients (derivation cohort) with replication in 99 patients (validation cohort). Death and progression along the World Health Organization (WHO) Clinical Progression Scale were assessed up to 21 days after the initial PCR test. Statistical methods included logistic regression, receiver operating curve (ROC) analysis and comparison of the area under the curve (AUC). FINDINGS: In the derivation cohort, 23 patients died, and 48 developed worse WHO scores. The odds ratios (OR) for death per 1 standard deviation (SD) increment in COV50 were 3·52 (95% CI, 2·02-6·13, p <0·0001) unadjusted and 2·73 (1·25-5·95, p = 0·012) adjusted for sex, age, baseline WHO score, body mass index (BMI) and comorbidities. For WHO scale progression, the corresponding OR were 2·63 (1·80-3·85, p<0·0001) and 3·38 (1·85-6·17, p<0·0001), respectively. The area under the curve (AUC) for COV50 as a continuously distributed variable was 0·80 (0·72-0·88) for mortality and 0·74 (0·66-0·81) for worsening WHO score. The optimised COV50 thresholds for mortality and worsening WHO score were 0·47 and 0·04 with sensitivity/specificity of 87·0 (74·6%) and 77·1 (63·9%), respectively. On top of covariates, COV50 improved the AUC, albeit borderline for death, from 0·78 to 0·82 (p = 0·11) and 0·84 (p = 0·052) for mortality and from 0·68 to 0·78 (p = 0·0097) and 0·75 (p = 0·021) for worsening WHO score. The validation cohort findings were confirmatory. INTERPRETATION: This first CRIT-COV-U report proves the concept that urinary proteomic profiling generates biomarkers indicating adverse COVID-19 outcomes, even at an early disease stage, including WHO stages 1-3. These findings need to be consolidated in an upcoming final dataset. FUNDING: The German Federal Ministry of Health funded the study.

Covid-19 in outpatients-Is fever a useful indicator for SARS-CoV-2 infection?

OBJECTIVE: Understanding mild to moderate symptoms of coronavirus disease 2019 (Covid-19) is important in order to identify active cases early and thus counteract transmission. METHODS: In March 2020, Leipzig University Hospital established an outpatient clinic for patients potentially infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Confirmed cases with mild to moderate symptoms self-isolated at home and were followed-up by daily telephone calls for at least 14 days. Symptoms and course of illness of these patients are reported here. RESULTS: From March 20 to April 17, 2020, 1460 individuals were tested for SARS-CoV-2 by naso- or oropharyngeal swab for real-time polymerase chain reaction (RT-PCR). Covid-19 was confirmed in 91 (6.2%) patients, of which 87 were included in the final analysis. Patients presented for testing after a mean of 5.9 days (IQR = 2.0-8.5). The median age was 37.0 years (IQR = 28.5-53), and 48 (55.2%) were female. Five (5.7%) patients required hospital admission during the course of illness. Most frequently reported symptoms were fatigue (n = 64, 74%), cough (n = 58, 67%), and hyposmia/hypogeusia (n = 44, 51%). In contrast to previous reports, fever occurred in less than a third of patients (n = 25, 29%). By day 14, more than half of the patients had recovered completely (n = 37/70, 52.9%). CONCLUSIONS: Fever seems to be less common in patients of relatively young age diagnosed with mild to moderate Covid-19. This suggests that body temperature alone may be an insufficient indicator of SARS-CoV-2 infection.

Comparison of pre-analytical characteristics for molecular and serological diagnostics of COVID-19.

Background: The diagnosis of SARS-CoV-2 infection relies on RT-PCR from nasopharyngeal swabs. The pre-analytical value of different methods of material harvesting for SARS-CoV-2 are unknown. Methods: We conducted a comprehensive investigation of the pre-analytical performance for different pharyngeal sampling procedures in hospitalized patients with confirmed SARS-CoV-2 infection. In addition to swabs taken simultaneously from different locations, saliva and pharyngeal lavages were also analyzed using RT-PCR. Results: In 10 COVID-19 patients, standard nasopharyngeal swabs detected 8 out of 10 positive patients, whereas swabs taken from the palatoglossal arch resulted in 9 correct-positive results. Brushing the posterior pharynx wall with swabs resulted in detection of 9 out of 10 positive patients with no difference using either dry swabs or liquid Amies medium. A strong correlation between Ct values of both swab materials was observed. Pharyngeal lavages yielded 6 out of 10 positive results in concordance with 85% of nasopharyngeal swabs in late-stage COVID-19 patients. Investigating 23 patients with early SARS-CoV-2 infection, pharyngeal lavages showed a concordance rate of 100% compared to nasopharyngeal swabs. Conclusions: The diagnostic performance of swabs taken from the palatoglossal arch in detecting SARS-CoV-2 infection is similar to that of specimens taken from the nasopharyngeal region. However, the former sampling method is associated with less discomfort and much easier to perform. Pharyngeal lavages may replace swabs for mass screening in early stages of SARS-CoV-2 infection. The predictive values are comparable, and the procedure is performed without exposing healthcare workers to transmission risks.

Differences of SARS-CoV-2 serological test performance between hospitalized and outpatient COVID-19 cases.

BACKGROUND: Serological severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody assays differ in the target antigen specificity, e.g. of antibodies directed against the viral spike or the nucleocapsid protein, and in the spectrum of detected immunoglobulins. The aim of the study was to evaluate the performance of two different routinely used immunoassays in hospitalized and outpatient COVID-19 cases. METHODS: The test characteristics of commercially available spike1 protein-based serological assays (Euroimmun, EI-assays), determining IgA or IgG and nucleocapsid-based assays (Virotech, VT-assays) determining IgA, IgM or IgG were compared in 139 controls and 116 hospitalized and outpatient COVID-19 cases. RESULTS: Hospitalized COVID-19 patients (n = 51; 115 samples) showed significantly higher concentrations of antibodies against SARS-CoV-2 and differed from outpatient cases (n = 65) by higher age, higher disease severity scores and earlier follow up blood sampling. Sensitivity of the two IgG assays was comparable in hospitalized patients tested ≥ 14 days (EI-assay: 88%, CI95% 67.6-99.9; VT-assay: 96%, CI95% 77.7-99.8). In outpatient COVID-19 cases sensitivity was significantly lower in the VT-assay (86.2%, CI95% 74.8-93.1) compared with the EI-assay (98.5%, CI95% 90.6-99.9). Assays for IgA and IgM demonstrated a lack of specificity or sensitivity. CONCLUSIONS: Our results indicate that SARS-CoV-2 serological assays may need to be optimized to produce reliable results in outpatient COVID-19 cases who are low or even asymptomatic. Assays for IgA and IgM have limited diagnostic performance and do not prove an additional value for population-based screening approaches.

Urinary Proteomics Associates with COVID-19 Severity: Pilot Proof-of-Principle Data and Design of a Multicentric Diagnostic Study.

SARS-CoV-2 infection results in a mild-to-moderate disease course in most patients, allowing outpatient self-care and quarantine. However, in approx. 10% of cases a two- or three-phasic critical disease course with starting from day 7 to 10 is observed. To facilitate and plan outpatient care, biomarkers prognosing such worsening at an early stage appear of outmost importance. In this accelerated article, we report on the identification of urinary peptides significantly associated with SARS-CoV-2 infection, and the development of a multi-marker urinary peptide based test, COVID20, that may enable prognosis of critical and fatal outcomes in COVID-19 patients. COVID20 is composed of 20 endogenous peptides mainly derived from various collagen chains that enable differentiating moderate or severe disease from critical state or death with 83% sensitivity at 100% specificity. Based on the performance in this pilot study, testing in a prospective study on 1000 patients has been initiated. This article is protected by copyright. All rights reserved.